Bump ajv from 6.12.2 to 6.12.6 in /spring-boot/thymeleaf-vue/client

Bumps [ajv](https://github.com/ajv-validator/ajv) from 6.12.2 to 6.12.6.
- [Release notes](https://github.com/ajv-validator/ajv/releases)
- [Commits](https://github.com/ajv-validator/ajv/compare/v6.12.2...v6.12.6)

---
updated-dependencies:
- dependency-name: ajv
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/ci.yml

@@ -17,7 +17,7 @@ jobs:
       matrix:
         # The MODULE environment variable is evaluated in build-all.sh to run a subset
         # of the builds. This way, multiple modules can be built in parallel.
-        module: [ "module1", "module2", "module3", "module4", "module5", "module6" ]
+        module: [ "module1", "module2", "module3", "module4", "module5", "module6", "module7" ]
 
     steps:
 

aws/cdkv2/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2007-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import java.net.*;
+import java.io.*;
+import java.nio.channels.*;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+    private static final String WRAPPER_VERSION = "0.5.6";
+    /**
+     * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+     */
+    private static final String DEFAULT_DOWNLOAD_URL = "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/"
+        + WRAPPER_VERSION + "/maven-wrapper-" + WRAPPER_VERSION + ".jar";
+
+    /**
+     * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+     * use instead of the default one.
+     */
+    private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+            ".mvn/wrapper/maven-wrapper.properties";
+
+    /**
+     * Path where the maven-wrapper.jar will be saved to.
+     */
+    private static final String MAVEN_WRAPPER_JAR_PATH =
+            ".mvn/wrapper/maven-wrapper.jar";
+
+    /**
+     * Name of the property which should be used to override the default download url for the wrapper.
+     */
+    private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+    public static void main(String args[]) {
+        System.out.println("- Downloader started");
+        File baseDirectory = new File(args[0]);
+        System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+        // If the maven-wrapper.properties exists, read it and check if it contains a custom
+        // wrapperUrl parameter.
+        File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+        String url = DEFAULT_DOWNLOAD_URL;
+        if(mavenWrapperPropertyFile.exists()) {
+            FileInputStream mavenWrapperPropertyFileInputStream = null;
+            try {
+                mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+                Properties mavenWrapperProperties = new Properties();
+                mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+                url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+            } catch (IOException e) {
+                System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+            } finally {
+                try {
+                    if(mavenWrapperPropertyFileInputStream != null) {
+                        mavenWrapperPropertyFileInputStream.close();
+                    }
+                } catch (IOException e) {
+                    // Ignore ...
+                }
+            }
+        }
+        System.out.println("- Downloading from: " + url);
+
+        File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+        if(!outputFile.getParentFile().exists()) {
+            if(!outputFile.getParentFile().mkdirs()) {
+                System.out.println(
+                        "- ERROR creating output directory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+            }
+        }
+        System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+        try {
+            downloadFileFromURL(url, outputFile);
+            System.out.println("Done");
+            System.exit(0);
+        } catch (Throwable e) {
+            System.out.println("- Error downloading");
+            e.printStackTrace();
+            System.exit(1);
+        }
+    }
+
+    private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+        if (System.getenv("MVNW_USERNAME") != null && System.getenv("MVNW_PASSWORD") != null) {
+            String username = System.getenv("MVNW_USERNAME");
+            char[] password = System.getenv("MVNW_PASSWORD").toCharArray();
+            Authenticator.setDefault(new Authenticator() {
+                @Override
+                protected PasswordAuthentication getPasswordAuthentication() {
+                    return new PasswordAuthentication(username, password);
+                }
+            });
+        }
+        URL website = new URL(urlString);
+        ReadableByteChannel rbc;
+        rbc = Channels.newChannel(website.openStream());
+        FileOutputStream fos = new FileOutputStream(destination);
+        fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+        fos.close();
+        rbc.close();
+    }
+
+}

aws/cdkv2/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,2 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.3/apache-maven-3.6.3-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar

aws/cdkv2/README.md

@@ -0,0 +1,8 @@
+# Getting started with AWS CDK
+
+
+
+Blog posts about this topic:
+
+* [Getting started with AWS CDK](https://reflectoring.io/getting-started-with-aws-cdk/)
+

aws/cdkv2/cdk.context.json

@@ -0,0 +1,51 @@
+{
+  "vpc-provider:account=675153449441:filter.isDefault=true:region=us-east-1:returnAsymmetricSubnets=true": {
+    "vpcId": "vpc-e5e76998",
+    "vpcCidrBlock": "172.31.0.0/16",
+    "availabilityZones": [],
+    "subnetGroups": [
+      {
+        "name": "Public",
+        "type": "Public",
+        "subnets": [
+          {
+            "subnetId": "subnet-d71e66f6",
+            "cidr": "172.31.80.0/20",
+            "availabilityZone": "us-east-1a",
+            "routeTableId": "rtb-ed425793"
+          },
+          {
+            "subnetId": "subnet-1783815a",
+            "cidr": "172.31.16.0/20",
+            "availabilityZone": "us-east-1b",
+            "routeTableId": "rtb-ed425793"
+          },
+          {
+            "subnetId": "subnet-71d8a72e",
+            "cidr": "172.31.32.0/20",
+            "availabilityZone": "us-east-1c",
+            "routeTableId": "rtb-ed425793"
+          },
+          {
+            "subnetId": "subnet-7ee39118",
+            "cidr": "172.31.0.0/20",
+            "availabilityZone": "us-east-1d",
+            "routeTableId": "rtb-ed425793"
+          },
+          {
+            "subnetId": "subnet-a56bed94",
+            "cidr": "172.31.48.0/20",
+            "availabilityZone": "us-east-1e",
+            "routeTableId": "rtb-ed425793"
+          },
+          {
+            "subnetId": "subnet-cc1e2ac2",
+            "cidr": "172.31.64.0/20",
+            "availabilityZone": "us-east-1f",
+            "routeTableId": "rtb-ed425793"
+          }
+        ]
+      }
+    ]
+  }
+}

aws/cdkv2/cdk.json

@@ -0,0 +1,27 @@
+{
+  "app": "mvn -e -q compile exec:java",
+  "watch": {
+    "include": [
+      "**"
+    ],
+    "exclude": [
+      "README.md",
+      "cdk*.json",
+      "target",
+      "pom.xml",
+      "src/test"
+    ]
+  },
+  "context": {
+    "@aws-cdk/aws-apigateway:usagePlanKeyOrderInsensitiveId": true,
+    "@aws-cdk/core:stackRelativeExports": true,
+    "@aws-cdk/aws-rds:lowercaseDbIdentifier": true,
+    "@aws-cdk/aws-lambda:recognizeVersionProps": true,
+    "@aws-cdk/aws-cloudfront:defaultSecurityPolicyTLSv1.2_2021": true,
+    "@aws-cdk-containers/ecs-service-extensions:enableDefaultLogDriver": true,
+    "@aws-cdk/core:target-partitions": [
+      "aws",
+      "aws-cn"
+    ]
+  }
+}

aws/cdkv2/mvnw

@@ -0,0 +1,310 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      jarUrl="$MVNW_REPOURL/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    else
+      jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget "$jarUrl" -O "$wrapperJarPath"
+        else
+            wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath"
+        fi
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl -o "$wrapperJarPath" "$jarUrl" -f
+        else
+            curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f
+        fi
+
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

aws/cdkv2/mvnw.cmd

@@ -0,0 +1,182 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    http://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+
+FOR /F "tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

aws/cdkv2/pom.xml

@@ -0,0 +1,61 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
+         xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>com.myorg</groupId>
+    <artifactId>cdk-app</artifactId>
+    <version>0.1</version>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <cdk.version>2.8.0</cdk.version>
+        <constructs.version>[10.0.0,11.0.0)</constructs.version>
+        <junit.version>5.7.1</junit.version>
+    </properties>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.8.1</version>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
+
+            <plugin>
+                <groupId>org.codehaus.mojo</groupId>
+                <artifactId>exec-maven-plugin</artifactId>
+                <version>3.0.0</version>
+                <configuration>
+                    <mainClass>com.myorg.CdkAppApp</mainClass>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+    <dependencies>
+        <!-- AWS Cloud Development Kit -->
+        <dependency>
+            <groupId>software.amazon.awscdk</groupId>
+            <artifactId>aws-cdk-lib</artifactId>
+            <version>${cdk.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>software.constructs</groupId>
+            <artifactId>constructs</artifactId>
+            <version>${constructs.version}</version>
+        </dependency>
+
+        <dependency>
+          <groupId>org.junit.jupiter</groupId>
+          <artifactId>junit-jupiter</artifactId>
+          <version>${junit.version}</version>
+          <scope>test</scope>
+        </dependency>
+    </dependencies>
+</project>

aws/cdkv2/src/main/java/com/myorg/CdkAppApp.java

@@ -0,0 +1,25 @@
+package com.myorg;
+
+import software.amazon.awscdk.App;
+import software.amazon.awscdk.Environment;
+import software.amazon.awscdk.StackProps;
+
+import java.util.Arrays;
+
+public class CdkAppApp {
+    public static void main(final String[] args) {
+        App app = new App();
+
+        new CdkAppStack(app, "CdkAppStack", StackProps.builder()
+         
+                .env(Environment.builder()
+                        .account("**********")
+                        .region("us-east-1")
+                        .build())
+                
+                .build());
+
+        app.synth();
+    }
+}
+

aws/cdkv2/src/main/java/com/myorg/CdkAppStack.java

@@ -0,0 +1,63 @@
+package com.myorg;
+
+import java.util.List;
+
+import org.jetbrains.annotations.NotNull;
+
+import software.amazon.awscdk.Stack;
+import software.amazon.awscdk.StackProps;
+import software.amazon.awscdk.services.ec2.BlockDeviceVolume;
+import software.amazon.awscdk.services.ec2.BlockDevice;
+import software.amazon.awscdk.services.ec2.IMachineImage;
+import software.amazon.awscdk.services.ec2.IVpc;
+import software.amazon.awscdk.services.ec2.Instance;
+import software.amazon.awscdk.services.ec2.InstanceClass;
+import software.amazon.awscdk.services.ec2.InstanceSize;
+import software.amazon.awscdk.services.ec2.InstanceType;
+import software.amazon.awscdk.services.ec2.MachineImage;
+import software.amazon.awscdk.services.ec2.SecurityGroup;
+import software.amazon.awscdk.services.ec2.Vpc;
+import software.amazon.awscdk.services.ec2.VpcLookupOptions;
+import software.constructs.Construct;
+// import software.amazon.awscdk.Duration;
+// import software.amazon.awscdk.services.sqs.Queue;
+
+public class CdkAppStack extends Stack {
+    public CdkAppStack(final Construct scope, final String id) {
+        this(scope, id, null);
+    }
+
+    public CdkAppStack(final Construct scope, final String id, final StackProps props) {
+        super(scope, id, props);
+        
+        
+		
+        VpcLookupOptions options = VpcLookupOptions.builder().isDefault(true).build();
+		IVpc vpc = Vpc.fromLookup(this, "vpc", options);
+       
+        
+        SecurityGroup securityGroup = SecurityGroup
+        		.Builder
+        		.create(this, "sg")
+        		.vpc(vpc)
+        		.allowAllOutbound(true)
+        		.build();
+        
+        
+
+        Instance.Builder.create(this, "Instance")
+		        .vpc(vpc)
+		        .instanceType(InstanceType.of(InstanceClass.BURSTABLE2, InstanceSize.MICRO))
+		        .machineImage(MachineImage.latestAmazonLinux())
+		        .blockDevices(List.of(BlockDevice.builder()
+		                .deviceName("/dev/sda1")
+		                .volume(BlockDeviceVolume.ebs(50))
+		                .build(), BlockDevice.builder()
+		                .deviceName("/dev/sdm")
+		                .volume(BlockDeviceVolume.ebs(100))
+		                .build()))
+		        .securityGroup(securityGroup)
+		        .build();
+        
+    }
+}

aws/cdkv2/src/main/java/com/myorg/MyStorageBucket.java

@@ -0,0 +1,34 @@
+/**
+ * 
+ */
+package com.myorg;
+
+
+
+import software.amazon.awscdk.Duration;
+import software.amazon.awscdk.services.s3.Bucket;
+import software.amazon.awscdk.services.s3.LifecycleRule;
+import software.constructs.Construct;
+
+/**
+ * @author pratikdas
+ *
+ */
+public class MyStorageBucket extends Construct{
+
+	public MyStorageBucket(final Construct scope, final String id) {
+		super(scope, id);
+		Bucket bucket = new Bucket(this, "mybucket");
+		
+		LifecycleRule lifecycleRule = LifecycleRule.builder()
+		         .abortIncompleteMultipartUploadAfter(Duration.minutes(30))
+		         .enabled(false)
+		         .expiration(Duration.minutes(30))
+		         .expiredObjectDeleteMarker(false)
+		         .id("id").build();
+		
+		bucket.addLifecycleRule(lifecycleRule);
+		
+	}
+
+}

aws/cdkv2/src/test/java/com/myorg/CdkAppTest.java

@@ -0,0 +1,26 @@
+// package com.myorg;
+
+// import software.amazon.awscdk.App;
+// import software.amazon.awscdk.assertions.Template;
+// import java.io.IOException;
+
+// import java.util.HashMap;
+
+// import org.junit.jupiter.api.Test;
+
+// example test. To run these tests, uncomment this file, along with the
+// example resource in java/src/main/java/com/myorg/CdkAppStack.java
+// public class CdkAppTest {
+
+//     @Test
+//     public void testStack() throws IOException {
+//         App app = new App();
+//         CdkAppStack stack = new CdkAppStack(app, "test");
+
+//         Template template = Template.fromStack(stack);
+
+//         template.hasResourceProperties("AWS::SQS::Queue", new HashMap<String, Number>() {{
+//           put("VisibilityTimeout", 300);
+//         }});
+//     }
+// }

aws/sqs/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2007-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import java.net.*;
+import java.io.*;
+import java.nio.channels.*;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+    private static final String WRAPPER_VERSION = "0.5.6";
+    /**
+     * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+     */
+    private static final String DEFAULT_DOWNLOAD_URL = "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/"
+        + WRAPPER_VERSION + "/maven-wrapper-" + WRAPPER_VERSION + ".jar";
+
+    /**
+     * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+     * use instead of the default one.
+     */
+    private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+            ".mvn/wrapper/maven-wrapper.properties";
+
+    /**
+     * Path where the maven-wrapper.jar will be saved to.
+     */
+    private static final String MAVEN_WRAPPER_JAR_PATH =
+            ".mvn/wrapper/maven-wrapper.jar";
+
+    /**
+     * Name of the property which should be used to override the default download url for the wrapper.
+     */
+    private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+    public static void main(String args[]) {
+        System.out.println("- Downloader started");
+        File baseDirectory = new File(args[0]);
+        System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+        // If the maven-wrapper.properties exists, read it and check if it contains a custom
+        // wrapperUrl parameter.
+        File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+        String url = DEFAULT_DOWNLOAD_URL;
+        if(mavenWrapperPropertyFile.exists()) {
+            FileInputStream mavenWrapperPropertyFileInputStream = null;
+            try {
+                mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+                Properties mavenWrapperProperties = new Properties();
+                mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+                url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+            } catch (IOException e) {
+                System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+            } finally {
+                try {
+                    if(mavenWrapperPropertyFileInputStream != null) {
+                        mavenWrapperPropertyFileInputStream.close();
+                    }
+                } catch (IOException e) {
+                    // Ignore ...
+                }
+            }
+        }
+        System.out.println("- Downloading from: " + url);
+
+        File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+        if(!outputFile.getParentFile().exists()) {
+            if(!outputFile.getParentFile().mkdirs()) {
+                System.out.println(
+                        "- ERROR creating output directory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+            }
+        }
+        System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+        try {
+            downloadFileFromURL(url, outputFile);
+            System.out.println("Done");
+            System.exit(0);
+        } catch (Throwable e) {
+            System.out.println("- Error downloading");
+            e.printStackTrace();
+            System.exit(1);
+        }
+    }
+
+    private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+        if (System.getenv("MVNW_USERNAME") != null && System.getenv("MVNW_PASSWORD") != null) {
+            String username = System.getenv("MVNW_USERNAME");
+            char[] password = System.getenv("MVNW_PASSWORD").toCharArray();
+            Authenticator.setDefault(new Authenticator() {
+                @Override
+                protected PasswordAuthentication getPasswordAuthentication() {
+                    return new PasswordAuthentication(username, password);
+                }
+            });
+        }
+        URL website = new URL(urlString);
+        ReadableByteChannel rbc;
+        rbc = Channels.newChannel(website.openStream());
+        FileOutputStream fos = new FileOutputStream(destination);
+        fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+        fos.close();
+        rbc.close();
+    }
+
+}

aws/sqs/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,2 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.3/apache-maven-3.6.3-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar

aws/sqs/README.md

@@ -0,0 +1,8 @@
+# Getting started with AWS SQS
+
+
+
+Blog posts about this topic:
+
+* [Getting started with AWS SQS](https://reflectoring.io/getting-started-with-aws-sqs/)
+

aws/sqs/mvnw

@@ -0,0 +1,310 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      jarUrl="$MVNW_REPOURL/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    else
+      jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget "$jarUrl" -O "$wrapperJarPath"
+        else
+            wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath"
+        fi
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl -o "$wrapperJarPath" "$jarUrl" -f
+        else
+            curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f
+        fi
+
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

aws/sqs/mvnw.cmd

@@ -0,0 +1,182 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    http://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+
+FOR /F "tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

aws/sqs/pom.xml

@@ -0,0 +1,58 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
+	xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
+	<modelVersion>4.0.0</modelVersion>
+
+	<groupId>io.pratik</groupId>
+	<artifactId>sqs</artifactId>
+	<version>1.0</version>
+
+	<properties>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+		
+	</properties>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-compiler-plugin</artifactId>
+				<version>3.8.1</version>
+				<configuration>
+					<source>1.8</source>
+					<target>1.8</target>
+				</configuration>
+			</plugin>
+
+			
+		</plugins>
+	</build>
+
+	<dependencies>
+
+		<dependency>
+		    <groupId>software.amazon.awssdk</groupId>
+		    <artifactId>sqs</artifactId>
+		</dependency>
+		
+		<dependency>
+		    <groupId>software.amazon.awssdk</groupId>
+		    <artifactId>sns</artifactId>
+		</dependency>
+
+
+	</dependencies>
+   <dependencyManagement>
+    <dependencies>
+      <dependency>
+        <groupId>software.amazon.awssdk</groupId>
+        <artifactId>bom</artifactId>
+        <version>2.17.116</version>
+        <type>pom</type>
+        <scope>import</scope>
+      </dependency>
+    </dependencies>
+   </dependencyManagement>
+</project>

aws/sqs/resources/index.js

@@ -0,0 +1,7 @@
+exports.handler = async function(event, context) {
+  event.Records.forEach(record => {
+    const { body } = record;
+    console.log(body);
+  });
+  return {};
+}

aws/sqs/src/main/java/io/pratik/sqs/AppConfig.java

@@ -0,0 +1,14 @@
+/**
+ * 
+ */
+package io.pratik.sqs;
+
+/**
+ * @author pratikdas
+ *
+ */
+public interface AppConfig {
+	
+	String ACCOUNT_NO = "*********";
+
+}

aws/sqs/src/main/java/io/pratik/sqs/MessageReceiver.java

@@ -0,0 +1,86 @@
+/**
+ * 
+ */
+package io.pratik.sqs;
+
+import java.util.List;
+
+import software.amazon.awssdk.auth.credentials.AwsCredentialsProvider;
+import software.amazon.awssdk.auth.credentials.ProfileCredentialsProvider;
+import software.amazon.awssdk.regions.Region;
+import software.amazon.awssdk.services.sqs.SqsClient;
+import software.amazon.awssdk.services.sqs.model.DeleteMessageRequest;
+import software.amazon.awssdk.services.sqs.model.DeleteMessageResponse;
+import software.amazon.awssdk.services.sqs.model.Message;
+import software.amazon.awssdk.services.sqs.model.ReceiveMessageRequest;
+
+/**
+ * @author pratikdas
+ *
+ */
+public class MessageReceiver {
+
+	/**
+	 * @param args
+	 * @throws InterruptedException 
+	 */
+	public static void main(String[] args) throws InterruptedException {
+		// receiveMessage();
+		receiveFifoMessage();
+
+	}
+	
+	public static void receiveMessage() {
+		SqsClient sqsClient = getSQSClient();
+		final String queueURL = "https://sqs.us-east-1.amazonaws.com/" +AppConfig.ACCOUNT_NO + "/myqueue";
+
+		// long polling and wait for waitTimeSeconds before timed out
+		ReceiveMessageRequest receiveMessageRequest = ReceiveMessageRequest.builder()
+		        .queueUrl(queueURL)
+		        .waitTimeSeconds(20)
+		        .messageAttributeNames("trace-id") // returns the trace Id
+		        .build();
+		List<Message> messages = sqsClient.receiveMessage(receiveMessageRequest).messages();
+	}
+	
+	public static void receiveFifoMessage() throws InterruptedException {
+		SqsClient sqsClient = getSQSClient();
+		final String queueURL = "https://sqs.us-east-1.amazonaws.com/" +AppConfig.ACCOUNT_NO + "/myfifoqueue.fifo";
+
+		// long polling and wait for waitTimeSeconds before timed out
+		ReceiveMessageRequest receiveMessageRequest = ReceiveMessageRequest.builder()
+		        .queueUrl(queueURL)
+		        .waitTimeSeconds(20)
+		        .messageAttributeNames("trace-id") // returns the trace Id
+		        .build();
+		
+		while(true) {
+		
+			Thread.sleep(20000l);
+			List<Message> messages = sqsClient.receiveMessage(receiveMessageRequest).messages();
+		    messages.stream().forEach(msg->{
+		    	System.out.println(msg.body() + " " + msg.attributesAsStrings());
+		    	
+		    	String receiptHandle = msg.receiptHandle();
+		    	DeleteMessageRequest deleteMessageRequest = DeleteMessageRequest.builder().queueUrl(queueURL).receiptHandle(receiptHandle).build();
+		    	DeleteMessageResponse deleteMessageResponse = sqsClient.deleteMessage(deleteMessageRequest );
+		    	
+		    	// logger.info(deleteMessageResponse.responseMetadata());
+		    });
+		
+		}
+	    
+	
+	}
+	
+	private static SqsClient getSQSClient() {
+		AwsCredentialsProvider credentialsProvider = ProfileCredentialsProvider.create("pratikpoc");
+		
+		SqsClient sqsClient = SqsClient
+				.builder()
+				.credentialsProvider(credentialsProvider)
+				.region(Region.US_EAST_1).build();
+		return sqsClient;
+	}
+
+}

aws/sqs/src/main/java/io/pratik/sqs/MessageSender.java

@@ -0,0 +1,147 @@
+/**
+ * 
+ */
+package io.pratik.sqs;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import java.util.logging.Logger;
+
+import software.amazon.awssdk.auth.credentials.AwsCredentialsProvider;
+import software.amazon.awssdk.auth.credentials.ProfileCredentialsProvider;
+import software.amazon.awssdk.regions.Region;
+import software.amazon.awssdk.services.sns.SnsClient;
+import software.amazon.awssdk.services.sns.model.PublishRequest;
+import software.amazon.awssdk.services.sns.model.PublishResponse;
+import software.amazon.awssdk.services.sqs.SqsClient;
+import software.amazon.awssdk.services.sqs.model.MessageAttributeValue;
+import software.amazon.awssdk.services.sqs.model.SendMessageRequest;
+import software.amazon.awssdk.services.sqs.model.SendMessageResponse;
+
+/**
+ * @author pratikdas
+ *
+ */
+public class MessageSender {
+
+	private static final String TRACE_ID_NAME = "trace-id";
+	private static Logger logger = Logger.getLogger(MessageSender.class.getName());
+
+	/**
+	 * @param args
+	 */
+	public static void main(String[] args) {
+		// sendMessage();
+		// sendMessageToFifo();
+		 sendMessageToSnsTopic();
+	}
+	public static void sendMessageToSnsTopic() {
+		SnsClient snsClient = getSNSClient();
+		
+		Map<String, MessageAttributeValue> messageAttributes = new HashMap<String, MessageAttributeValue>();
+		// generates a UUID as the traceId
+		String traceId = UUID.randomUUID().toString();
+		// add traceId as a message attribute
+		messageAttributes.put(TRACE_ID_NAME, MessageAttributeValue.builder().dataType("String").stringValue(traceId).build());
+		final String topicArn = "arn:aws:sns:us-east-1:" + AppConfig.ACCOUNT_NO + ":mytopic";
+
+		PublishRequest publishRequest = PublishRequest.builder().topicArn(topicArn).message("Test message published to topic").build();
+		PublishResponse publishResponse = snsClient.publish(publishRequest);
+		
+		logger.info("message id: "+ publishResponse.messageId());
+		
+		snsClient.close();
+	}
+	
+
+	public static void sendMessage() {
+		SqsClient sqsClient = getSQSClient();
+		
+		Map<String, MessageAttributeValue> messageAttributes = new HashMap<String, MessageAttributeValue>();
+		// generates a UUID as the traceId
+		String traceId = UUID.randomUUID().toString();
+		// add traceId as a message attribute
+		messageAttributes.put(TRACE_ID_NAME, MessageAttributeValue.builder().dataType("String").stringValue(traceId).build());
+		
+		final String queueURL = "https://sqs.us-east-1.amazonaws.com/" +AppConfig.ACCOUNT_NO + "/myqueue";
+		SendMessageRequest sendMessageRequest = SendMessageRequest.builder().queueUrl(queueURL).messageBody("Test message")
+				.messageAttributes(messageAttributes)
+				.build();
+		SendMessageResponse sendMessageResponse = sqsClient.sendMessage(sendMessageRequest);
+		
+		logger.info("message id: "+ sendMessageResponse.messageId() );
+		
+		sqsClient.close();
+	}
+	
+	public static void sendMessageToFifo() {
+		SqsClient sqsClient = getSQSClient();
+		
+		Map<String, MessageAttributeValue> messageAttributes = new HashMap<String, MessageAttributeValue>();
+		// generates a UUID as the traceId
+		String traceId = UUID.randomUUID().toString();
+		// add traceId as a message attribute
+		messageAttributes.put(TRACE_ID_NAME, MessageAttributeValue.builder().dataType("String").stringValue(traceId).build());
+		
+		final String queueURL = "https://sqs.us-east-1.amazonaws.com/" +AppConfig.ACCOUNT_NO + "/myfifoqueue.fifo";
+		
+		
+		List<String> dedupIds = List.of("dedupid1","dedupid2","dedupid3","dedupid2","dedupid1");
+		
+		String messageGroupId = "signup";
+		
+		List<String> messages = List.of(
+								"My fifo message1",
+								"My fifo message2",
+								"My fifo message3",
+								"My fifo message2",
+								"My fifo message1");
+		short loop = 0;
+		for (String message : messages) {
+			
+			SendMessageRequest sendMessageRequest = SendMessageRequest.builder()
+					.queueUrl(queueURL)
+					.messageBody(message)
+					.messageAttributes(messageAttributes)
+					.messageDeduplicationId(dedupIds.get(loop))
+					.messageGroupId(messageGroupId)
+					.build();
+			
+			SendMessageResponse sendMessageResponse = sqsClient
+					.sendMessage(sendMessageRequest);
+			
+			logger.info("message id and sequence no.: "+ sendMessageResponse.messageId() + " | " + sendMessageResponse.sequenceNumber());
+			
+			logger.info("responseMetadata " + sendMessageResponse.responseMetadata());
+			loop+=1;
+		}
+
+		
+		sqsClient.close();
+	}
+
+
+
+	private static SqsClient getSQSClient() {
+		AwsCredentialsProvider credentialsProvider = ProfileCredentialsProvider.create("pratikpoc");
+		
+		SqsClient sqsClient = SqsClient
+				.builder()
+				.credentialsProvider(credentialsProvider)
+				.region(Region.US_EAST_1).build();
+		return sqsClient;
+	}
+	
+	private static SnsClient getSNSClient() {
+		AwsCredentialsProvider credentialsProvider = ProfileCredentialsProvider.create("pratikpoc");
+		
+		SnsClient snsClient = SnsClient
+				.builder()
+				.credentialsProvider(credentialsProvider)
+				.region(Region.US_EAST_1).build();
+		return snsClient;
+	}
+
+}

aws/sqs/src/main/java/io/pratik/sqs/ResourceHelper.java

@@ -0,0 +1,138 @@
+/**
+ * 
+ */
+package io.pratik.sqs;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.logging.Logger;
+
+import software.amazon.awssdk.auth.credentials.AwsCredentialsProvider;
+import software.amazon.awssdk.auth.credentials.ProfileCredentialsProvider;
+import software.amazon.awssdk.regions.Region;
+import software.amazon.awssdk.services.sns.SnsClient;
+import software.amazon.awssdk.services.sns.model.CreateTopicRequest;
+import software.amazon.awssdk.services.sns.model.CreateTopicResponse;
+import software.amazon.awssdk.services.sns.model.SubscribeRequest;
+import software.amazon.awssdk.services.sns.model.SubscribeResponse;
+import software.amazon.awssdk.services.sqs.SqsClient;
+import software.amazon.awssdk.services.sqs.model.CreateQueueRequest;
+import software.amazon.awssdk.services.sqs.model.CreateQueueResponse;
+import software.amazon.awssdk.services.sqs.model.QueueAttributeName;
+
+/**
+ * @author pratikdas
+ *
+ */
+public class ResourceHelper {
+	private static Logger logger = Logger.getLogger(ResourceHelper.class.getName());
+	
+	public static void main(String[] args) {
+		// createStandardQueue();
+		// createFifoQueue();
+		createSNSTopicWithSubscription();
+	}
+	
+
+	
+	public static void createStandardQueue() {
+		SqsClient sqsClient = getSQSClient();
+		
+		String dlqName = "mydlq";
+		CreateQueueRequest createQueueRequest = CreateQueueRequest.builder()
+									                .queueName(dlqName)
+									                .build();
+		
+
+		// Create dead letter queue
+		CreateQueueResponse createQueueResponse = sqsClient.createQueue(createQueueRequest);
+		
+		
+		String dlqArn = getQueueArn(dlqName,"us-east-1"); 
+		
+		Map<QueueAttributeName, String> attributeMap = new HashMap<QueueAttributeName, String>();
+		attributeMap.put(QueueAttributeName.REDRIVE_POLICY, 
+				"{\"maxReceiveCount\":10,\"deadLetterTargetArn\":\""+dlqArn+"\"}");
+	    
+		// Prepare request for creating the standard queue
+		createQueueRequest = CreateQueueRequest.builder()
+                .queueName("myqueue")
+                .attributes(attributeMap)
+                .build();
+
+		// create the queue
+	    createQueueResponse = sqsClient.createQueue(createQueueRequest);
+	    
+	    logger.info("Queue URL " + createQueueResponse.queueUrl());
+	}
+	
+	public static void createFifoQueue() {
+		SqsClient sqsClient = getSQSClient();
+		
+		
+		Map<QueueAttributeName, String> attributeMap = new HashMap<QueueAttributeName, String>();
+		
+		attributeMap.put(QueueAttributeName.FIFO_QUEUE, "true");
+		attributeMap.put(QueueAttributeName.DEDUPLICATION_SCOPE, "messageGroup");
+		attributeMap.put(QueueAttributeName.CONTENT_BASED_DEDUPLICATION, "false");
+		
+		CreateQueueRequest createQueueRequest = CreateQueueRequest.builder()
+                .queueName("myfifoqueue.fifo")
+                .attributes(attributeMap )
+                .build();
+
+		CreateQueueResponse createQueueResponse = sqsClient.createQueue(createQueueRequest);
+        logger.info("url "+createQueueResponse.queueUrl());
+	}
+	
+	public static void createSNSTopicWithSubscription() {
+		SnsClient snsClient = getSNSClient();
+		
+		CreateTopicRequest createTopicRequest = CreateTopicRequest.builder().name("mytopic").build();
+		CreateTopicResponse createTopicResponse = snsClient.createTopic(createTopicRequest );
+		
+		String topicArn = createTopicResponse.topicArn();
+		//Topic topic = Topic.builder().topicArn(topicArn).build();
+
+		String queueArn= getQueueArn("myqueue","us-east-1");
+		
+		SubscribeRequest subscribeRequest = SubscribeRequest.builder()
+															.protocol("sqs")
+															.topicArn(topicArn)
+															.endpoint(queueArn)
+															.build();
+		SubscribeResponse subscribeResponse = snsClient.subscribe(subscribeRequest );
+
+	    
+	    logger.info("subscriptionArn " + subscribeResponse.subscriptionArn());
+	}
+	
+
+	
+	private static SqsClient getSQSClient() {
+		AwsCredentialsProvider credentialsProvider = ProfileCredentialsProvider.create("pratikpoc");
+		
+		SqsClient sqsClient = SqsClient
+				.builder()
+				.credentialsProvider(credentialsProvider)
+				.region(Region.US_EAST_1).build();
+		return sqsClient;
+	}
+	
+	private static SnsClient getSNSClient() {
+		AwsCredentialsProvider credentialsProvider = ProfileCredentialsProvider.create("pratikpoc");
+		
+		SnsClient snsClient = SnsClient
+				.builder()
+				.credentialsProvider(credentialsProvider)
+				.region(Region.US_EAST_1).build();
+		return snsClient;
+	}
+	
+
+	
+	private static String getQueueArn(final String queueName, final String region) {
+		return "arn:aws:sqs:"+region + ":" + AppConfig.ACCOUNT_NO+ ":" + queueName;
+	}
+
+}

build-all.sh

@@ -82,10 +82,28 @@ build_maven_module() {
   }
 }
 
-if [[ "$MODULE" == "module6" ]]
+
+if [[ "$MODULE" == "module7" ]]
 then
   # ADD NEW MODULES HERE
   # (add new modules above the rest so you get quicker feedback if it fails)
+  build maven_module "aws/sqs"
+  build_maven_module "core-java/annotation-processing/introduction-to-annotations"
+
+  echo ""
+  echo "+++"
+  echo "+++ MODULE 7 SUCCESSFUL"
+  echo "+++"
+fi
+
+
+if [[ "$MODULE" == "module6" ]]
+then
+  build_maven_module "spring-boot/spring-boot-null-safe-annotations"
+  build maven_module "aws/cdkv2"
+  build_maven_module "immutables"
+  build maven_module "core-java/collectionops"
+  build maven_module "spring-boot/resttemplate"
   build_maven_module "spring-cloud/tracing"
   build_maven_module "core-java/versions"
   build maven_module "java-hashes"
@@ -104,7 +122,7 @@ then
   build_maven_module "logging/spring-boot"
   build_maven_module "logging/logback"
   build_maven_module "logging/log4j"
-
+  
   echo ""
   echo "+++"
   echo "+++ MODULE 6 SUCCESSFUL"

core-java/annotation-processing/introduction-to-annotations/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2007-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import java.net.*;
+import java.io.*;
+import java.nio.channels.*;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+    private static final String WRAPPER_VERSION = "0.5.6";
+    /**
+     * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+     */
+    private static final String DEFAULT_DOWNLOAD_URL = "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/"
+        + WRAPPER_VERSION + "/maven-wrapper-" + WRAPPER_VERSION + ".jar";
+
+    /**
+     * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+     * use instead of the default one.
+     */
+    private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+            ".mvn/wrapper/maven-wrapper.properties";
+
+    /**
+     * Path where the maven-wrapper.jar will be saved to.
+     */
+    private static final String MAVEN_WRAPPER_JAR_PATH =
+            ".mvn/wrapper/maven-wrapper.jar";
+
+    /**
+     * Name of the property which should be used to override the default download url for the wrapper.
+     */
+    private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+    public static void main(String args[]) {
+        System.out.println("- Downloader started");
+        File baseDirectory = new File(args[0]);
+        System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+        // If the maven-wrapper.properties exists, read it and check if it contains a custom
+        // wrapperUrl parameter.
+        File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+        String url = DEFAULT_DOWNLOAD_URL;
+        if(mavenWrapperPropertyFile.exists()) {
+            FileInputStream mavenWrapperPropertyFileInputStream = null;
+            try {
+                mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+                Properties mavenWrapperProperties = new Properties();
+                mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+                url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+            } catch (IOException e) {
+                System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+            } finally {
+                try {
+                    if(mavenWrapperPropertyFileInputStream != null) {
+                        mavenWrapperPropertyFileInputStream.close();
+                    }
+                } catch (IOException e) {
+                    // Ignore ...
+                }
+            }
+        }
+        System.out.println("- Downloading from: " + url);
+
+        File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+        if(!outputFile.getParentFile().exists()) {
+            if(!outputFile.getParentFile().mkdirs()) {
+                System.out.println(
+                        "- ERROR creating output directory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+            }
+        }
+        System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+        try {
+            downloadFileFromURL(url, outputFile);
+            System.out.println("Done");
+            System.exit(0);
+        } catch (Throwable e) {
+            System.out.println("- Error downloading");
+            e.printStackTrace();
+            System.exit(1);
+        }
+    }
+
+    private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+        if (System.getenv("MVNW_USERNAME") != null && System.getenv("MVNW_PASSWORD") != null) {
+            String username = System.getenv("MVNW_USERNAME");
+            char[] password = System.getenv("MVNW_PASSWORD").toCharArray();
+            Authenticator.setDefault(new Authenticator() {
+                @Override
+                protected PasswordAuthentication getPasswordAuthentication() {
+                    return new PasswordAuthentication(username, password);
+                }
+            });
+        }
+        URL website = new URL(urlString);
+        ReadableByteChannel rbc;
+        rbc = Channels.newChannel(website.openStream());
+        FileOutputStream fos = new FileOutputStream(destination);
+        fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+        fos.close();
+        rbc.close();
+    }
+
+}

core-java/annotation-processing/introduction-to-annotations/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,2 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.3/apache-maven-3.6.3-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar

core-java/annotation-processing/introduction-to-annotations/README.md

@@ -0,0 +1,3 @@
+# Introduction to Annotation Processing
+
+Blog article: [An Introduction to Annotations and Annotation Processing in Java](https://reflectoring.io/java-annotation-processing)

core-java/annotation-processing/introduction-to-annotations/mvnw

@@ -0,0 +1,310 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      jarUrl="$MVNW_REPOURL/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    else
+      jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget "$jarUrl" -O "$wrapperJarPath"
+        else
+            wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath"
+        fi
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl -o "$wrapperJarPath" "$jarUrl" -f
+        else
+            curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f
+        fi
+
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

core-java/annotation-processing/introduction-to-annotations/mvnw.cmd

@@ -0,0 +1,182 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    http://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+
+FOR /F "tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

core-java/annotation-processing/introduction-to-annotations/pom.xml

@@ -0,0 +1,16 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>org.example</groupId>
+    <artifactId>annotations-demo</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <properties>
+        <maven.compiler.source>11</maven.compiler.source>
+        <maven.compiler.target>11</maven.compiler.target>
+    </properties>
+
+</project>

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/AnnotatedMethods.java

@@ -0,0 +1,15 @@
+package com.reflectoring;
+
+public class AnnotatedMethods {
+
+    @Test
+    public void Test_1() {
+
+        System.out.println("This is the first test");
+    }
+
+    public void Test_2() {
+
+        System.out.println("This is the second test");
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/BasicAnnotationTest.java

@@ -0,0 +1,8 @@
+package com.reflectoring;
+
+public class BasicAnnotationTest {
+
+    public static void main(String[] args) {
+
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/ClassRetention.java

@@ -0,0 +1,11 @@
+package com.reflectoring;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.CLASS)
+public @interface ClassRetention {
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/Company.java

@@ -0,0 +1,12 @@
+package com.reflectoring;
+
+import java.lang.annotation.*;
+
+@Inherited
+@Documented
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface Company{
+    String name() default "ABC";
+    String city() default "XYZ";
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/CustomAnnotatedEmployee.java

@@ -0,0 +1,19 @@
+package com.reflectoring;
+
+@Company
+public class CustomAnnotatedEmployee {
+
+    private int id;
+    private String name;
+
+    public CustomAnnotatedEmployee(int id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public void getEmployeeDetails(){
+
+        System.out.println("Employee Id: " + id);
+        System.out.println("Employee Name: " + name);
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/CustomAnnotatedManager.java

@@ -0,0 +1,8 @@
+package com.reflectoring;
+
+public class CustomAnnotatedManager extends CustomAnnotatedEmployee{
+
+    public CustomAnnotatedManager(int id, String name) {
+        super(id, name);
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/DeprecatedDemo.java

@@ -0,0 +1,10 @@
+package com.reflectoring;
+
+public class DeprecatedDemo {
+
+    @Deprecated(since = "4.5", forRemoval = true)
+    public void testLegacyFunction() {
+
+        System.out.println("This is a legacy function");
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/DeprecatedDemoTest.java

@@ -0,0 +1,10 @@
+package com.reflectoring;
+
+public class DeprecatedDemoTest {
+
+    public static void main(String[] args) {
+
+        DeprecatedDemo demo = new DeprecatedDemo();
+        demo.testLegacyFunction();
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/Employee.java

@@ -0,0 +1,10 @@
+package com.reflectoring;
+
+@Company
+public class Employee {
+
+    public void getEmployeeStatus(){
+
+        System.out.println("This is the Base Employee class");
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/EmployeeRetentionAnnotation.java

@@ -0,0 +1,7 @@
+package com.reflectoring;
+
+@SourceRetention
+@RuntimeRetention
+@ClassRetention
+public class EmployeeRetentionAnnotation {
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/FunctionalInterfaceTest.java

@@ -0,0 +1,15 @@
+package com.reflectoring;
+
+@FunctionalInterface
+interface Print {
+    void printString(String testString);
+}
+
+public class FunctionalInterfaceTest {
+
+    public static void main(String args[]) {
+
+        Print testPrint = (String testString) -> System.out.println(testString);
+        testPrint.printString("This is a String");
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/Manager.java

@@ -0,0 +1,10 @@
+package com.reflectoring;
+
+public class Manager extends Employee {
+
+    @Override
+    public void getEmployeeStatus(){
+
+        System.out.println("This is the Manager class");
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/MultiValueAnnotatedEmployee.java

@@ -0,0 +1,6 @@
+package com.reflectoring;
+
+@Company(name = "AAA", city = "ZZZ")
+public class MultiValueAnnotatedEmployee {
+
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/OverrideTest.java

@@ -0,0 +1,10 @@
+package com.reflectoring;
+
+public class OverrideTest {
+
+    public static void main(String[] args) {
+
+        Manager manager = new Manager();
+        manager.getEmployeeStatus();
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/RepeatableCompanies.java

@@ -0,0 +1,9 @@
+package com.reflectoring;
+
+import java.lang.annotation.*;
+
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface RepeatableCompanies {
+    RepeatableCompany[] value() default{};
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/RepeatableCompany.java

@@ -0,0 +1,11 @@
+package com.reflectoring;
+
+import java.lang.annotation.*;
+
+@Target(ElementType.TYPE)
+@Repeatable(RepeatableCompanies.class)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface RepeatableCompany {
+    String name() default "Name_1";
+    String city() default "City_1";
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/RepeatedAnnotatedEmployee.java

@@ -0,0 +1,6 @@
+package com.reflectoring;
+
+@RepeatableCompany
+@RepeatableCompany(name =  "Name_2", city = "City_2")
+public class RepeatedAnnotatedEmployee {
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/RetentionTest.java

@@ -0,0 +1,16 @@
+package com.reflectoring;
+
+public class RetentionTest {
+
+    public static void main(String[] args) {
+
+        SourceRetention[] sourceRetention = new EmployeeRetentionAnnotation().getClass().getAnnotationsByType(SourceRetention.class);
+        System.out.println("Source Retentions at run-time: " + sourceRetention.length);
+
+        RuntimeRetention[] runtimeRetention = new EmployeeRetentionAnnotation().getClass().getAnnotationsByType(RuntimeRetention.class);
+        System.out.println("Run-time Retentions at run-time: " + runtimeRetention.length);
+
+        ClassRetention[] classRetention = new EmployeeRetentionAnnotation().getClass().getAnnotationsByType(ClassRetention.class);
+        System.out.println("Class Retentions at run-time: " + classRetention.length);
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/RuntimeRetention.java

@@ -0,0 +1,11 @@
+package com.reflectoring;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface RuntimeRetention {
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/SafeVarargsTest.java

@@ -0,0 +1,57 @@
+package com.reflectoring;
+
+import java.util.Arrays;
+import java.util.List;
+
+public class SafeVarargsTest {
+
+    private void printString(String test1) {
+
+        System.out.println(test1);
+    }
+
+    private void printString(String test1, String test2) {
+
+        System.out.println(test1);
+        System.out.println(test2);
+    }
+
+    private void printStringVarargs(String... tests) {
+
+        for (String test : tests) {
+
+            System.out.println(test);
+        }
+    }
+
+    @SafeVarargs
+    private void printStringSafeVarargs(List<String>... testStringLists) {
+
+        for (List<String> testStringList : testStringLists) {
+
+            for (String testString : testStringList) {
+
+                System.out.println(testString);
+            }
+        }
+    }
+
+    public static void main(String[] args) {
+
+        SafeVarargsTest test = new SafeVarargsTest();
+
+        test.printString("String1");
+        test.printString("*******");
+
+        test.printString("String1", "String2");
+        test.printString("*******");
+
+        test.printStringVarargs("String1", "String2");
+        test.printString("*******");
+
+        List<String> testStringList1 = Arrays.asList("One", "Two");
+        List<String> testStringList2 = Arrays.asList("Three", "Four");
+
+        test.printStringSafeVarargs(testStringList1, testStringList2);
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/SingleValueAnnotatedEmployee.java

@@ -0,0 +1,19 @@
+package com.reflectoring;
+
+@SingleValueAnnotationCompany("XYZ")
+public class SingleValueAnnotatedEmployee {
+
+    private int id;
+    private String name;
+
+    public SingleValueAnnotatedEmployee(int id, String name) {
+        this.id = id;
+        this.name = name;
+    }
+
+    public void getEmployeeDetails(){
+
+        System.out.println("Employee Id: " + id);
+        System.out.println("Employee Name: " + name);
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/SingleValueAnnotationCompany.java

@@ -0,0 +1,9 @@
+package com.reflectoring;
+
+import java.lang.annotation.*;
+
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.RUNTIME)
+public @interface SingleValueAnnotationCompany {
+    String value() default "ABC";
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/SourceRetention.java

@@ -0,0 +1,8 @@
+package com.reflectoring;
+
+import java.lang.annotation.*;
+
+@Target(ElementType.TYPE)
+@Retention(RetentionPolicy.SOURCE)
+public @interface SourceRetention {
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/SuppressWarningsDemo.java

@@ -0,0 +1,22 @@
+package com.reflectoring;
+
+import java.util.HashMap;
+import java.util.Map;
+
+@SuppressWarnings({"rawtypes", "unchecked"})
+public class SuppressWarningsDemo {
+
+    public static void main(String[] args) {
+
+        SuppressWarningsDemo swDemo = new SuppressWarningsDemo();
+        swDemo.testSuppressWarning();
+    }
+
+    public void testSuppressWarning() {
+
+        Map testMap = new HashMap();
+        testMap.put(1, "Item_1");
+        testMap.put(2, "Item_2");
+        testMap.put(3, "Item_3");
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/Test.java

@@ -0,0 +1,11 @@
+package com.reflectoring;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+@Retention(RetentionPolicy.RUNTIME)
+@Target(ElementType.METHOD)
+public @interface Test {
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/TestAnnotatedMethods.java

@@ -0,0 +1,31 @@
+package com.reflectoring;
+
+import java.lang.annotation.Annotation;
+import java.lang.reflect.Method;
+
+public class TestAnnotatedMethods {
+
+    public static void main(String[] args) throws Exception {
+
+        Class<AnnotatedMethods> annotatedMethodsClass = AnnotatedMethods.class;
+
+        for (Method method : annotatedMethodsClass.getDeclaredMethods()) {
+
+            Annotation annotation = method.getAnnotation(Test.class);
+            Test test = (Test) annotation;
+
+            // If the annotation is not null
+            if (test != null) {
+
+                try {
+                    method.invoke(annotatedMethodsClass.getDeclaredConstructor().newInstance());
+                } catch (Throwable ex) {
+                    System.out.println(ex.getCause());
+                }
+
+            }
+        }
+    }
+}
+
+

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/TestCustomAnnotatedEmployee.java

@@ -0,0 +1,18 @@
+package com.reflectoring;
+
+import java.lang.annotation.Annotation;
+
+public class TestCustomAnnotatedEmployee {
+
+    public static void main(String[] args) {
+
+        CustomAnnotatedEmployee employee = new CustomAnnotatedEmployee(1, "John Doe");
+        employee.getEmployeeDetails();
+
+        Annotation companyAnnotation = employee.getClass().getAnnotation(Company.class);
+        Company company = (Company)companyAnnotation;
+
+        System.out.println("Company Name: " + company.name());
+        System.out.println("Company City: " + company.city());
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/TestCustomAnnotatedManager.java

@@ -0,0 +1,18 @@
+package com.reflectoring;
+
+import java.lang.annotation.Annotation;
+
+public class TestCustomAnnotatedManager {
+
+    public static void main(String[] args) {
+
+        CustomAnnotatedManager manager = new CustomAnnotatedManager(1, "John Doe");
+        manager.getEmployeeDetails();
+
+        Annotation companyAnnotation = manager.getClass().getAnnotation(Company.class);
+        Company company = (Company)companyAnnotation;
+
+        System.out.println("Company Name: " + company.name());
+        System.out.println("Company City: " + company.city());
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/TestMultiValueAnnotatedEmployee.java

@@ -0,0 +1,17 @@
+package com.reflectoring;
+
+import java.lang.annotation.Annotation;
+
+public class TestMultiValueAnnotatedEmployee {
+
+    public static void main(String[] args) {
+
+        MultiValueAnnotatedEmployee employee = new MultiValueAnnotatedEmployee();
+
+        Annotation companyAnnotation = employee.getClass().getAnnotation(Company.class);
+        Company company = (Company)companyAnnotation;
+
+        System.out.println("Company Name: " + company.name());
+        System.out.println("Company City: " + company.city());
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/TestRepeatedAnnotation.java

@@ -0,0 +1,14 @@
+package com.reflectoring;
+
+public class TestRepeatedAnnotation {
+
+    public static void main(String[] args) {
+
+        RepeatableCompany[] repeatableCompanies = RepeatedAnnotatedEmployee.class.getAnnotationsByType(RepeatableCompany.class);
+        for (RepeatableCompany repeatableCompany : repeatableCompanies) {
+
+            System.out.println("Name: " + repeatableCompany.name());
+            System.out.println("City: " + repeatableCompany.city());
+        }
+    }
+}

core-java/annotation-processing/introduction-to-annotations/src/main/java/com/reflectoring/TestSingleValueAnnotatedEmployee.java

@@ -0,0 +1,17 @@
+package com.reflectoring;
+
+import java.lang.annotation.Annotation;
+
+public class TestSingleValueAnnotatedEmployee {
+
+    public static void main(String[] args) {
+
+        SingleValueAnnotatedEmployee employee = new SingleValueAnnotatedEmployee(1, "John Doe");
+        employee.getEmployeeDetails();
+
+        Annotation companyAnnotation = employee.getClass().getAnnotation(SingleValueAnnotationCompany.class);
+        SingleValueAnnotationCompany company = (SingleValueAnnotationCompany)companyAnnotation;
+
+        System.out.println("Company Name: " + company.value());
+    }
+}

core-java/collectionops/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2007-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import java.net.*;
+import java.io.*;
+import java.nio.channels.*;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+    private static final String WRAPPER_VERSION = "0.5.6";
+    /**
+     * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+     */
+    private static final String DEFAULT_DOWNLOAD_URL = "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/"
+        + WRAPPER_VERSION + "/maven-wrapper-" + WRAPPER_VERSION + ".jar";
+
+    /**
+     * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+     * use instead of the default one.
+     */
+    private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+            ".mvn/wrapper/maven-wrapper.properties";
+
+    /**
+     * Path where the maven-wrapper.jar will be saved to.
+     */
+    private static final String MAVEN_WRAPPER_JAR_PATH =
+            ".mvn/wrapper/maven-wrapper.jar";
+
+    /**
+     * Name of the property which should be used to override the default download url for the wrapper.
+     */
+    private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+    public static void main(String args[]) {
+        System.out.println("- Downloader started");
+        File baseDirectory = new File(args[0]);
+        System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+        // If the maven-wrapper.properties exists, read it and check if it contains a custom
+        // wrapperUrl parameter.
+        File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+        String url = DEFAULT_DOWNLOAD_URL;
+        if(mavenWrapperPropertyFile.exists()) {
+            FileInputStream mavenWrapperPropertyFileInputStream = null;
+            try {
+                mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+                Properties mavenWrapperProperties = new Properties();
+                mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+                url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+            } catch (IOException e) {
+                System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+            } finally {
+                try {
+                    if(mavenWrapperPropertyFileInputStream != null) {
+                        mavenWrapperPropertyFileInputStream.close();
+                    }
+                } catch (IOException e) {
+                    // Ignore ...
+                }
+            }
+        }
+        System.out.println("- Downloading from: " + url);
+
+        File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+        if(!outputFile.getParentFile().exists()) {
+            if(!outputFile.getParentFile().mkdirs()) {
+                System.out.println(
+                        "- ERROR creating output directory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+            }
+        }
+        System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+        try {
+            downloadFileFromURL(url, outputFile);
+            System.out.println("Done");
+            System.exit(0);
+        } catch (Throwable e) {
+            System.out.println("- Error downloading");
+            e.printStackTrace();
+            System.exit(1);
+        }
+    }
+
+    private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+        if (System.getenv("MVNW_USERNAME") != null && System.getenv("MVNW_PASSWORD") != null) {
+            String username = System.getenv("MVNW_USERNAME");
+            char[] password = System.getenv("MVNW_PASSWORD").toCharArray();
+            Authenticator.setDefault(new Authenticator() {
+                @Override
+                protected PasswordAuthentication getPasswordAuthentication() {
+                    return new PasswordAuthentication(username, password);
+                }
+            });
+        }
+        URL website = new URL(urlString);
+        ReadableByteChannel rbc;
+        rbc = Channels.newChannel(website.openStream());
+        FileOutputStream fos = new FileOutputStream(destination);
+        fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+        fos.close();
+        rbc.close();
+    }
+
+}

core-java/collectionops/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,2 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.6.3/apache-maven-3.6.3-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar

core-java/collectionops/README.md

@@ -0,0 +1,3 @@
+# Related Blog Posts
+
+* [Logical Operations Between Java Collections](https://reflectoring.io/logical-ops-on-java-collections/)

core-java/collectionops/mvnw

@@ -0,0 +1,310 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      jarUrl="$MVNW_REPOURL/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    else
+      jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget "$jarUrl" -O "$wrapperJarPath"
+        else
+            wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath"
+        fi
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl -o "$wrapperJarPath" "$jarUrl" -f
+        else
+            curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f
+        fi
+
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

core-java/collectionops/mvnw.cmd

@@ -0,0 +1,182 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    http://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+
+FOR /F "tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

core-java/collectionops/pom.xml

@@ -0,0 +1,24 @@
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>io.pratik</groupId>
+	<artifactId>logicalops</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+
+	<dependencies>
+		<!-- https://mvnrepository.com/artifact/org.apache.commons/commons-collections4 -->
+		<dependency>
+			<groupId>org.apache.commons</groupId>
+			<artifactId>commons-collections4</artifactId>
+			<version>4.4</version>
+		</dependency>
+		<dependency>
+		    <groupId>com.google.guava</groupId>
+		    <artifactId>guava</artifactId>
+		    <version>31.0.1-jre</version>
+		</dependency>
+
+
+	</dependencies>
+</project>

core-java/collectionops/src/main/java/io/pratik/CollectionHelper.java

@@ -0,0 +1,135 @@
+/**
+ * 
+ */
+package io.pratik;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.LinkedHashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.stream.Collectors;
+import java.util.stream.IntStream;
+import java.util.stream.Stream;
+
+import com.google.common.collect.Lists;
+
+/**
+ * @author pratikdas
+ *
+ */
+public class CollectionHelper {
+	
+	public <T> List<T>[] split(List<T> listToSplit){
+	    // determine the endpoints to use in `list.subList()` method
+	    int[] endpoints = {0, (listToSplit.size() + 1)/2, listToSplit.size()};
+	 
+	    
+	    List<List<T>> sublists =
+	            IntStream.rangeClosed(0, 1)
+	                    .mapToObj(i -> listToSplit.subList(endpoints[i], endpoints[i + 1]))
+	                    .collect(Collectors.toList());
+	 
+	    // return an array containing both lists
+	    return new List[] {sublists.get(0), sublists.get(1)};
+	}
+	
+	public List<Integer> add(final List<Integer> collA, final List<Integer> collB){
+
+		return Stream.concat(collA.stream(), 
+				collB.stream())
+		.collect(Collectors.toList());
+		
+		
+	}	
+	
+	public List<Integer> addWithFilter(final List<Integer> collA, final List<Integer> collB){
+
+		return Stream.concat(collA.stream(), 
+				collB.stream())
+				.filter(element -> element > 2 )
+		.collect(Collectors.toList());
+	}	
+	
+	public List<Integer> union(final List<Integer> collA, final List<Integer> collB){
+		Set<Integer> set = new LinkedHashSet<>();
+		set.addAll(collA);
+		set.addAll(collB);
+		
+		return new ArrayList<>(set);
+		
+	}
+	
+	public List<Integer> intersection(final List<Integer> collA, final List<Integer> collB){
+		List<Integer> intersectElements = collA.stream()
+				.filter(collB :: contains)
+				.collect(Collectors.toList());
+		
+		if(!intersectElements.isEmpty()) {
+			return intersectElements;
+		}else {
+			return Collections.emptyList();
+		}
+		
+	}
+	
+	public Collection<List<Integer>> partition(final List<Integer> collA, final int chunkSize){
+		final AtomicInteger counter = new AtomicInteger();
+
+		final Collection<List<Integer>> result = collA.stream()
+		    .collect(Collectors.groupingBy(it -> counter.getAndIncrement() / chunkSize))
+		    .values();
+
+		return result;
+		
+	}
+	
+
+	public List<Integer> removeDuplicates(final List<Integer> collA){
+      List<Integer> listWithoutDuplicates = new ArrayList<>(
+         new LinkedHashSet<>(collA));
+      
+      return listWithoutDuplicates;
+	}
+	
+	public List<Integer> xor(final List<Integer> collA, final List<Integer> collB){
+	      
+	      List<Integer> listOfAnotInB = collA.stream().filter(element->{
+	    	  return !collB.contains(element);
+	      }).collect(Collectors.toList());
+	      
+	      List<Integer> listOfBnotInA = collB.stream().filter(element->{
+	    	  return !collA.contains(element);
+	      }).collect(Collectors.toList());
+	      
+	      return Stream.concat(listOfAnotInB.stream(), 
+	    		  listOfBnotInA.stream())
+	    			.collect(Collectors.toList());
+	}
+	
+	public List<Integer> not(final List<Integer> collA, final List<Integer> collB){
+		  
+		  List<Integer> notList = collA.stream().filter(element->{
+	    	  return !collB.contains(element);
+	      }).collect(Collectors.toList());
+	      
+	      return notList;
+	}
+	
+	public List<Integer> subtract(final List<Integer> collA, final List<Integer> collB){
+		List<Integer> intersectElements = intersection(collA,collB);
+		
+		List<Integer> subtractedElements = collA.stream().filter(element->!intersectElements.contains(element)).collect(Collectors.toList());
+		
+		if(!subtractedElements.isEmpty()) {
+			return subtractedElements;
+		}else {
+			return Collections.emptyList();
+		}
+		
+	}
+
+}

core-java/collectionops/src/test/java/io/pratik/tests/CollectionHelperTest.java

@@ -0,0 +1,178 @@
+/**
+ * 
+ */
+package io.pratik.tests;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+
+import java.util.Collection;
+import java.util.Iterator;
+import java.util.List;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import io.pratik.CollectionHelper;
+
+/**
+ * @author pratikdas
+ *
+ */
+class CollectionHelperTest {
+	
+	private CollectionHelper collectionHelper;
+
+	/**
+	 * @throws java.lang.Exception
+	 */
+	@BeforeEach
+	void setUp() throws Exception {
+		collectionHelper = new CollectionHelper();
+	}
+
+	/**
+	 * @throws java.lang.Exception
+	 */
+	@AfterEach
+	void tearDown() throws Exception {
+	}
+
+	@Test
+	void testUnion() {
+		List<Integer> union = collectionHelper.union(
+				List.of(9, 8, 5, 4, 7), 
+				List.of(1, 3, 99, 4, 7));
+		
+		
+		Assertions.assertArrayEquals(
+				List.of(9, 8, 5, 4, 7, 1, 3, 99).toArray(), 
+				union.toArray());
+		
+	}
+	
+	@Test
+	void testIntersection() {
+		List<Integer> intersection = collectionHelper.intersection(
+				List.of(9,8,5,4,7, 15, 15), 
+				List.of(1,3,99,4,7));
+		
+		Assertions.assertArrayEquals(
+				List.of(4,7).toArray(), 
+				intersection.toArray());
+	}
+	
+	@Test
+	void testXOR() {
+		List<Integer> xorList = collectionHelper.xor(
+				List.of(9, 8,  5, 4, 7), 
+				List.of(1, 99, 4, 7));
+		
+		Assertions.assertArrayEquals(
+				List.of(9, 8, 5, 1, 99).toArray(), 
+				xorList.toArray());
+	}
+	
+	@Test
+	void testNOT() {
+		List<Integer> xorList = collectionHelper.not(
+				List.of(9,8,5,4,7), 
+				List.of(1,99,4,7));
+		
+		Assertions.assertArrayEquals(
+				List.of(9,8,5).toArray(), 
+				xorList.toArray());
+	}
+	
+	@Test
+	void testAddition() {
+		List<Integer> sub = collectionHelper.add(
+				List.of(9,8,5,4), 
+				List.of(1,3,99,4,7));
+		
+		
+		Assertions.assertArrayEquals(
+				List.of(9,8,5,4,1,3,99,4,7).toArray(), 
+				sub.toArray());
+	}
+	
+	@Test
+	void testAdditionWithFilter() {
+		List<Integer> list = collectionHelper.addWithFilter(
+				List.of(9,8,5,4), 
+				List.of(1,3,99,4,7));
+		
+		
+		Assertions.assertArrayEquals(
+				List.of(9,8,5,4,3,99,4,7).toArray(), 
+				list.toArray());
+	}
+
+	
+	@Test
+	void testSubtraction() {
+		List<Integer> sub = collectionHelper.subtract(
+				List.of(9,8,5,4,7, 15, 15), 
+				List.of(1,3,99,4,7));
+		
+		
+		Assertions.assertArrayEquals(
+				List.of(9,8,5,15,15).toArray(), 
+				sub.toArray());
+	}
+	
+	@Test
+	void testPartition() {
+		Collection<List<Integer>> partitions = collectionHelper.partition(
+				List.of(9, 8, 5, 4, 7, 15, 15), 2);
+		
+		Iterator<List<Integer>> iter = partitions.iterator();
+		
+		int loop = 0;
+		while(iter.hasNext()) {
+			List<Integer> element = iter.next();
+			System.out.println(element);
+			if(loop == 0)
+			   assertArrayEquals(List.of(9, 8).toArray(),element.toArray());
+			else if(loop == 1)
+				   assertArrayEquals(List.of(5, 4).toArray(),element.toArray());
+			else if(loop == 2)
+				   assertArrayEquals(List.of(7, 15).toArray(),element.toArray());
+			else if(loop == 3)
+				   assertArrayEquals(List.of(15).toArray(),element.toArray());
+		
+			++loop;
+		}
+		
+	
+	}
+	
+	@Test
+	void testRemoveDuplicates() {
+		List<Integer> uniqueElements = collectionHelper.removeDuplicates(
+				List.of(9, 8, 5, 4, 4, 7, 15, 15));
+		
+		
+		
+		Assertions.assertArrayEquals(
+				List.of(9, 8, 5, 4, 7, 15).toArray(), 
+				uniqueElements.toArray());
+	}
+	
+	@Test
+	void testSplit() {
+		List<Integer>[] subLists = collectionHelper.split(
+				List.of(9, 8, 5, 4, 7, 15, 15));
+		
+		
+		Assertions.assertArrayEquals(
+				List.of(9,8,5,4).toArray(), 
+				subLists[0].toArray());
+		
+		Assertions.assertArrayEquals(
+				List.of(7,15,15).toArray(), 
+				subLists[1].toArray());
+	}
+
+}

immutables/.gitignore

@@ -0,0 +1,33 @@
+HELP.md
+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/

immutables/.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,118 @@
+/*
+ * Copyright 2007-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.net.*;
+import java.io.*;
+import java.nio.channels.*;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+    private static final String WRAPPER_VERSION = "0.5.6";
+    /**
+     * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+     */
+    private static final String DEFAULT_DOWNLOAD_URL = "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/"
+            + WRAPPER_VERSION + "/maven-wrapper-" + WRAPPER_VERSION + ".jar";
+
+    /**
+     * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+     * use instead of the default one.
+     */
+    private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+            ".mvn/wrapper/maven-wrapper.properties";
+
+    /**
+     * Path where the maven-wrapper.jar will be saved to.
+     */
+    private static final String MAVEN_WRAPPER_JAR_PATH =
+            ".mvn/wrapper/maven-wrapper.jar";
+
+    /**
+     * Name of the property which should be used to override the default download url for the wrapper.
+     */
+    private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+    public static void main(String args[]) {
+        System.out.println("- Downloader started");
+        File baseDirectory = new File(args[0]);
+        System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+        // If the maven-wrapper.properties exists, read it and check if it contains a custom
+        // wrapperUrl parameter.
+        File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+        String url = DEFAULT_DOWNLOAD_URL;
+        if (mavenWrapperPropertyFile.exists()) {
+            FileInputStream mavenWrapperPropertyFileInputStream = null;
+            try {
+                mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+                Properties mavenWrapperProperties = new Properties();
+                mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+                url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+            } catch (IOException e) {
+                System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+            } finally {
+                try {
+                    if (mavenWrapperPropertyFileInputStream != null) {
+                        mavenWrapperPropertyFileInputStream.close();
+                    }
+                } catch (IOException e) {
+                    // Ignore ...
+                }
+            }
+        }
+        System.out.println("- Downloading from: " + url);
+
+        File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+        if (!outputFile.getParentFile().exists()) {
+            if (!outputFile.getParentFile().mkdirs()) {
+                System.out.println(
+                        "- ERROR creating output directory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+            }
+        }
+        System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+        try {
+            downloadFileFromURL(url, outputFile);
+            System.out.println("Done");
+            System.exit(0);
+        } catch (Throwable e) {
+            System.out.println("- Error downloading");
+            e.printStackTrace();
+            System.exit(1);
+        }
+    }
+
+    private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+        if (System.getenv("MVNW_USERNAME") != null && System.getenv("MVNW_PASSWORD") != null) {
+            String username = System.getenv("MVNW_USERNAME");
+            char[] password = System.getenv("MVNW_PASSWORD").toCharArray();
+            Authenticator.setDefault(new Authenticator() {
+                @Override
+                protected PasswordAuthentication getPasswordAuthentication() {
+                    return new PasswordAuthentication(username, password);
+                }
+            });
+        }
+        URL website = new URL(urlString);
+        ReadableByteChannel rbc;
+        rbc = Channels.newChannel(website.openStream());
+        FileOutputStream fos = new FileOutputStream(destination);
+        fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+        fos.close();
+        rbc.close();
+    }
+
+}

immutables/.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,2 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.8.3/apache-maven-3.8.3-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar

immutables/mvnw

@@ -0,0 +1,310 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      jarUrl="$MVNW_REPOURL/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    else
+      jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget "$jarUrl" -O "$wrapperJarPath"
+        else
+            wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath"
+        fi
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl -o "$wrapperJarPath" "$jarUrl" -f
+        else
+            curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f
+        fi
+
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

immutables/mvnw.cmd

@@ -0,0 +1,182 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    https://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+
+FOR /F "tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

immutables/pom.xml

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+    <groupId>com.reflectoring.io</groupId>
+    <artifactId>immutables</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>immutables</name>
+    <description>immutables</description>
+    <properties>
+        <java.version>11</java.version>
+    </properties>
+    <dependencies>
+        <dependency>
+            <groupId>org.immutables</groupId>
+            <artifactId>value</artifactId>
+            <version>2.8.8</version>
+        </dependency>
+    </dependencies>
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <configuration>
+                    <source>11</source>
+                    <target>11</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>

immutables/src/main/java/com/reflectoring/io/immutables/Role.java

@@ -0,0 +1,13 @@
+package com.reflectoring.io.immutables;
+
+public enum Role {
+    WRITER("writer"),
+    READER("reader");
+
+    public final String value;
+
+    Role(String value){
+        this.value = value;
+    }
+
+}

immutables/src/main/java/com/reflectoring/io/immutables/basic/Article.java

@@ -0,0 +1,17 @@
+package com.reflectoring.io.immutables.basic;
+
+
+import org.immutables.value.Value;
+
+
+@Value.Immutable
+public abstract class Article {
+
+    abstract long getId();
+
+    abstract String getTitle();
+
+    abstract String getContent();
+
+    abstract long getUserId();
+}

immutables/src/main/java/com/reflectoring/io/immutables/basic/ArticleService.java

@@ -0,0 +1,27 @@
+package com.reflectoring.io.immutables.basic;
+
+import java.util.List;
+
+public class ArticleService {
+
+    // Explain how to create Immutable object the simplest way possible.
+    // Show generated class and class that we created
+    public static void main(String[] args) {
+        Article article = ImmutableArticle.builder()
+                .id(0)
+                .content("Lorem ipsum dolor sit amet.")
+                .title("Lorem ipsum article!")
+                .userId(1l)
+                .build();
+
+        User user = ImmutableUser.builder()
+                .id(1l)
+                .name("Mateo")
+                .lastname("Stjepanovic")
+                .email("mateo@mock.com")
+                .password("password")
+                .articles(List.of(article))
+                .build();
+        System.out.println(user);
+    }
+}

immutables/src/main/java/com/reflectoring/io/immutables/basic/User.java

@@ -0,0 +1,23 @@
+package com.reflectoring.io.immutables.basic;
+
+
+import org.immutables.value.Value;
+
+import java.util.List;
+
+
+@Value.Immutable
+public abstract class User {
+
+    public abstract long getId();
+
+    public abstract String getName();
+
+    public abstract String getLastname();
+
+    public abstract String getEmail();
+
+    public abstract  String getPassword();
+
+    public abstract List<Article> getArticles();
+}

immutables/src/main/java/com/reflectoring/io/immutables/builders/BuildersService.java

@@ -0,0 +1,33 @@
+package com.reflectoring.io.immutables.builders;
+
+public class BuildersService {
+
+    public static void main(String[] args) {
+//        StrictBuilderArticle strictBuilderArticle =
+//                createStrictArticle();
+        StagedBuilderArticle stagedBuilderArticle = createStagedArticle();
+    }
+
+    // Show how strict builder works
+    // Show error that is provided
+    public static StrictBuilderArticle createStrictArticle(){
+        return ImmutableStrictBuilderArticle.builder()
+                .id(0)
+                .id(1)
+                .build();
+    }
+
+    // Staged article is strict implicitly
+    // Staged article does now allow calling build method if not all mandatory fields are set
+    // Downside of using staged builders
+
+    public static StagedBuilderArticle createStagedArticle(){
+        return ImmutableStagedBuilderArticle.builder()
+                .id(0)
+                .title("Lorem ipsum article!")
+                .content("Lore ipsum...")
+                .build();
+    }
+
+
+}

immutables/src/main/java/com/reflectoring/io/immutables/builders/StagedBuilderArticle.java

@@ -0,0 +1,14 @@
+package com.reflectoring.io.immutables.builders;
+
+import org.immutables.value.Value;
+
+@Value.Immutable
+@Value.Style(stagedBuilder = true)
+abstract class StagedBuilderArticle {
+
+    abstract long getId();
+
+    abstract String getTitle();
+
+    abstract String getContent();
+}

immutables/src/main/java/com/reflectoring/io/immutables/builders/StrictBuilderArticle.java

@@ -0,0 +1,13 @@
+package com.reflectoring.io.immutables.builders;
+
+import org.immutables.value.Value;
+
+@Value.Immutable
+@Value.Style(strictBuilder = true)
+abstract class StrictBuilderArticle {
+    abstract long getId();
+
+    abstract String getTitle();
+
+    abstract String getContent();
+}

immutables/src/main/java/com/reflectoring/io/immutables/collections/CollectionsService.java

@@ -0,0 +1,46 @@
+package com.reflectoring.io.immutables.collections;
+
+import com.reflectoring.io.immutables.basic.Article;
+import com.reflectoring.io.immutables.basic.ImmutableArticle;
+import com.reflectoring.io.immutables.basic.ImmutableUser;
+import com.reflectoring.io.immutables.basic.User;
+
+public class CollectionsService {
+
+    public static void main(String[] args) {
+
+        Article article1 = ImmutableArticle.builder()
+                .id(0l)
+                .title("Lorem ipsum!")
+                .content("Lorem ipsum")
+                .userId(1l)
+                .build();
+
+        Article article2 = ImmutableArticle.builder()
+                .id(2l)
+                .title("Lorem ipsum!")
+                .content("Lorem ipsum")
+                .userId(1l)
+                .build();
+
+        Article article3 = ImmutableArticle.builder()
+                .id(3l)
+                .title("Lorem ipsum!")
+                .content("Lorem ipsum")
+                .userId(1l)
+                .build();
+        User user = ImmutableUser.builder()
+                .id(1l)
+                .name("Mateo")
+                .lastname("Stjepanovic")
+                .email("mock@mock.com")
+                .password("mock")
+                .addArticles(article1)
+                .addArticles(article2)
+                .build();
+        System.out.println(user);
+
+        user.getArticles().add(article3);
+
+    }
+}

immutables/src/main/java/com/reflectoring/io/immutables/constructor/ConstructorArticle.java

@@ -0,0 +1,13 @@
+package com.reflectoring.io.immutables.constructor;
+
+import org.immutables.value.Value;
+
+@Value.Immutable
+public abstract class ConstructorArticle {
+    @Value.Parameter
+    public abstract long getId();
+    @Value.Parameter
+    public abstract String getTitle();
+    @Value.Parameter
+    public abstract String getContent();
+}

immutables/src/main/java/com/reflectoring/io/immutables/constructor/ConstructorsService.java

@@ -0,0 +1,17 @@
+package com.reflectoring.io.immutables.constructor;
+
+public class ConstructorsService {
+    public static void main(String[] args) {
+
+    }
+
+    // Out of the box constructor
+    public static ConstructorArticle createConstructorArticle(){
+        return ImmutableConstructorArticle.of(0,"Lorem ipsum article!", "Lorem ipsum...");
+    }
+
+    // How to use standard new constructor
+    public static PlainPublicConstructorArticle createPlainPublicConstructorArticle(){
+        return new ImmutablePlainPublicConstructorArticle(0,"Lorem ipsum","Lorem ipsum...");
+    }
+}

immutables/src/main/java/com/reflectoring/io/immutables/constructor/PlainPublicConstructorArticle.java

@@ -0,0 +1,14 @@
+package com.reflectoring.io.immutables.constructor;
+
+import org.immutables.value.Value;
+
+@Value.Immutable
+@Value.Style(of = "new")
+public abstract class PlainPublicConstructorArticle {
+    @Value.Parameter
+    public abstract long getId();
+    @Value.Parameter
+    public abstract String getTitle();
+    @Value.Parameter
+    public abstract String getContent();
+}

immutables/src/main/java/com/reflectoring/io/immutables/derivedAndLazy/DerivedAndLazyService.java

@@ -0,0 +1,16 @@
+package com.reflectoring.io.immutables.derivedAndLazy;
+
+public class DerivedAndLazyService {
+
+    public static void main(String[] args) {
+        DerivedArticle article = ImmutableDerivedArticle.builder()
+                .id(1l)
+                .title("Lorem ipsum")
+                .content("Lorem ipsum dolor sit amet, consectetur " +
+                        "adipiscing elit. Donec ut sem lectus. " +
+                        "Nulla dapibus eros.")
+                .build();
+
+        System.out.println(article);
+    }
+}

immutables/src/main/java/com/reflectoring/io/immutables/derivedAndLazy/DerivedArticle.java

@@ -0,0 +1,22 @@
+package com.reflectoring.io.immutables.derivedAndLazy;
+
+import org.immutables.value.Value;
+
+@Value.Immutable
+abstract class DerivedArticle {
+
+    abstract Long getId();
+
+    abstract String getTitle();
+
+    abstract String getContent();
+
+    @Value.Derived
+    String getSummary(){
+        String summary = getContent().substring(0,
+                getContent().length()>50 ? 50 :
+                        getContent().length());
+        return summary.length() == getContent().length() ? summary
+                : summary+"...";
+    }
+}

immutables/src/main/java/com/reflectoring/io/immutables/derivedAndLazy/LazyArticle.java

@@ -0,0 +1,23 @@
+package com.reflectoring.io.immutables.derivedAndLazy;
+
+import org.immutables.value.Value;
+
+@Value.Immutable
+abstract class LazyArticle {
+
+    abstract Long getId();
+    
+    abstract String getTitle();
+
+    abstract String getContent();
+
+    @Value.Lazy
+    String summary(){
+        String summary = getContent().substring(0,
+                getContent().length()>50 ? 50 :
+                        getContent().length());
+        return summary.length() == getContent().length() ? summary
+                : summary+"...";
+    }
+
+}

immutables/src/main/java/com/reflectoring/io/immutables/optionalAndDefault/DefaultArticle.java

@@ -0,0 +1,17 @@
+package com.reflectoring.io.immutables.optionalAndDefault;
+
+import org.immutables.value.Value;
+
+@Value.Immutable
+abstract class DefaultArticle {
+
+    abstract Long getId();
+
+    @Value.Default
+    String getTitle(){
+        return "Default title!";
+    }
+
+    abstract String getContent();
+
+}

immutables/src/main/java/com/reflectoring/io/immutables/optionalAndDefault/DefaultArticleInterface.java

@@ -0,0 +1,17 @@
+package com.reflectoring.io.immutables.optionalAndDefault;
+
+import org.immutables.value.Value;
+
+@Value.Immutable
+interface DefaultArticleInterface {
+
+    Long getId();
+
+    @Value.Default
+    default String getTitle(){
+        return "Default title!";
+    }
+
+    String getContent();
+
+}

immutables/src/main/java/com/reflectoring/io/immutables/optionalAndDefault/OptionalAndDefaultService.java

@@ -0,0 +1,23 @@
+package com.reflectoring.io.immutables.optionalAndDefault;
+
+public class OptionalAndDefaultService {
+
+    //Explain optional and how we can omit values
+    //Explain default and how we use it
+    public static void main(String[] args) {
+        OptionalArticle article =  ImmutableOptionalArticle.builder().build();
+        DefaultArticle defaultArticle = ImmutableDefaultArticle.builder()
+                .id(0l)
+                .content("Lorem ipsum!")
+                .build();
+
+        DefaultArticleInterface defaultArticleInterface =
+                ImmutableDefaultArticleInterface.builder()
+                        .id(0l)
+                        .content("Lorem ipsum!")
+                        .build();
+
+        System.out.println(defaultArticle);
+        System.out.println(defaultArticleInterface);
+    }
+}

immutables/src/main/java/com/reflectoring/io/immutables/optionalAndDefault/OptionalArticle.java

@@ -0,0 +1,15 @@
+package com.reflectoring.io.immutables.optionalAndDefault;
+
+import org.immutables.value.Value;
+
+import java.util.Optional;
+
+@Value.Immutable
+abstract class OptionalArticle {
+
+    abstract Optional<Long> getId();
+
+    abstract Optional<String> getTitle();
+
+    abstract Optional<String> getContent();
+}

immutables/src/main/java/com/reflectoring/io/immutables/styles/CustomStyle.java

@@ -0,0 +1,23 @@
+package com.reflectoring.io.immutables.styles;
+
+import org.immutables.value.Value;
+
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+// How does styles work
+// Where we can put it
+// Thing to be aware of and tests of those
+
+@Target({ElementType.PACKAGE,ElementType.TYPE})
+@Retention(RetentionPolicy.CLASS)
+@Value.Style(
+        of = "new",
+        strictBuilder = true,
+        allParameters = true,
+        visibility = Value.Style.ImplementationVisibility.PUBLIC
+
+)
+public @interface CustomStyle {}