added to build-all.sh

add project spring-boot/password-encoding

build-all.sh

@@ -28,8 +28,40 @@ build_gradle_module() {
   }
 }
 
+build_maven_module() {
+  MODULE_PATH=$1
+  echo ""
+  echo "+++"
+  echo "+++ BUILDING MODULE $MODULE_PATH"
+  echo "+++"
+  cd $MODULE_PATH && {
+    chmod +x mvnw
+    ./mvnw clean package
+    if [ $? -ne 0 ]
+    then
+      echo ""
+      echo "+++"
+      echo "+++ BUILDING MODULE $MODULE_PATH FAILED"
+      echo "+++"
+      exit 1
+    else
+      echo ""
+      echo "+++"
+      echo "+++ BUILDING MODULE $MODULE_PATH SUCCESSFUL"
+      echo "+++"
+    fi
+    cd $MAIN_DIR
+  }
+}
+
 chmod +x gradlew
 
+build_maven_module "spring-boot/spring-boot-openapi"
+build_gradle_module "spring-boot/boundaries"
+build_gradle_module "spring-boot/argumentresolver"
+build_gradle_module "spring-data/spring-data-jdbc-converter"
+build_gradle_module "solid"
+build_gradle_module "spring-boot/data-migration/flyway"
 build_gradle_module "reactive"
 build_gradle_module "junit/assumptions"
 build_gradle_module "logging"
@@ -52,6 +84,7 @@ build_gradle_module "spring-boot/startup"
 build_gradle_module "spring-boot/static"
 build_gradle_module "spring-boot/validation"
 build_gradle_module "spring-boot/profiles"
+build_gradle_module "spring-boot/password-encoding"
 build_gradle_module "spring-cloud/feign-with-spring-data-rest"
 build_gradle_module "spring-cloud/sleuth-downstream-service"
 build_gradle_module "spring-cloud/sleuth-upstream-service"

solid/build.gradle

@@ -0,0 +1,25 @@
+buildscript {
+	repositories {
+		jcenter()
+	}
+}
+
+apply plugin: 'java'
+apply plugin: 'java-library'
+
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = 8
+
+repositories {
+	mavenLocal()
+	mavenCentral()
+}
+
+dependencies {
+	testImplementation 'org.junit.jupiter:junit-jupiter-engine:5.0.1'
+	testImplementation 'org.assertj:assertj-core:2.6.0'
+}
+
+test {
+	useJUnitPlatform()
+}

solid/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.1-bin.zip

solid/gradlew

@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+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"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+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
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"

solid/gradlew.bat

@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

solid/src/main/java/io/reflectoring/solid/isp/BetterOrderService.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+interface BetterOrderService {
+    void submitOrder(Order order);
+}

solid/src/main/java/io/reflectoring/solid/isp/BurgerOrderService.java

@@ -0,0 +1,18 @@
+package io.reflectoring.solid.isp;
+
+class BurgerOrderService implements OrderService {
+    @Override
+    public void orderBurger(int quantity) {
+        System.out.println("Received order of "+quantity+" burgers");
+    }
+
+    @Override
+    public void orderFries(int fries) {
+        throw new UnsupportedOperationException("No fries in burger only order");
+    }
+
+    @Override
+    public void orderCombo(int quantity, int fries) {
+        throw new UnsupportedOperationException("No combo in burger only order");
+    }
+}

solid/src/main/java/io/reflectoring/solid/isp/ComboOrderService.java

@@ -0,0 +1,18 @@
+package io.reflectoring.solid.isp;
+
+class ComboOrderService implements OrderService{
+    @Override
+    public void orderBurger(int quantity) {
+        System.out.println("Received order of "+quantity+" burgers");
+    }
+
+    @Override
+    public void orderFries(int fries) {
+        System.out.println("Received order of "+fries+ " fries");
+    }
+
+    @Override
+    public void orderCombo(int quantity, int fries) {
+        System.out.println("Received order of "+quantity+" burgers and "+ fries+" fries");
+    }
+}

solid/src/main/java/io/reflectoring/solid/isp/FriesOrderService.java

@@ -0,0 +1,19 @@
+package io.reflectoring.solid.isp;
+
+class FriesOrderService implements OrderService {
+    @Override
+    public void orderBurger(int quantity) {
+        throw new UnsupportedOperationException("No burger in fries only order");
+    }
+
+    @Override
+    public void orderFries(int fries) {
+        System.out.println("Received order of "+fries+ " fries");
+    }
+
+    @Override
+    public void orderCombo(int quantity, int fries) {
+        throw new UnsupportedOperationException("No combo in fries only order");
+    }
+}
+

solid/src/main/java/io/reflectoring/solid/isp/Main.java

@@ -0,0 +1,10 @@
+package io.reflectoring.solid.isp;
+
+class Main{
+    public static void main(String[] args){
+        OrderService comboOrderService = new ComboOrderService();
+        NewBurgerOrderService burgerService =
+            new OrderServiceObjectAdapter(new ComboOrderService());
+        burgerService.orderBurger(4);
+    }
+}

solid/src/main/java/io/reflectoring/solid/isp/NewBurgerOrderService.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+interface NewBurgerOrderService {
+    void orderBurger(int quantity);
+}

solid/src/main/java/io/reflectoring/solid/isp/NewFriesOrderService.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+interface NewFriesOrderService {
+    void orderFries(int fries);
+}

solid/src/main/java/io/reflectoring/solid/isp/Order.java

@@ -0,0 +1,5 @@
+package io.reflectoring.solid.isp;
+
+class Order {
+    // define order
+}

solid/src/main/java/io/reflectoring/solid/isp/OrderService.java

@@ -0,0 +1,7 @@
+package io.reflectoring.solid.isp;
+
+interface OrderService {
+    void orderBurger(int quantity);
+    void orderFries(int fries);
+    void orderCombo(int quantity, int fries);
+}

solid/src/main/java/io/reflectoring/solid/isp/OrderServiceObjectAdapter.java

@@ -0,0 +1,14 @@
+package io.reflectoring.solid.isp;
+
+class OrderServiceObjectAdapter implements NewBurgerOrderService {
+    private OrderService adaptee;
+    public OrderServiceObjectAdapter(OrderService adaptee) {
+        super();
+        this.adaptee = adaptee;
+    }
+
+    @Override
+    public void orderBurger(int quantity) {
+        adaptee.orderBurger(quantity);
+    }
+}

spring-boot/argumentresolver/.gitignore

@@ -0,0 +1,32 @@
+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/

spring-boot/argumentresolver/build.gradle

@@ -0,0 +1,28 @@
+plugins {
+	id 'org.springframework.boot' version '2.2.5.RELEASE'
+	id 'io.spring.dependency-management' version '1.0.9.RELEASE'
+	id 'java'
+}
+
+group = 'io.reflectoring'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '11'
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter'
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	testImplementation('org.springframework.boot:spring-boot-starter-test') {
+		exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
+	}
+
+	compileOnly 'org.projectlombok:lombok'
+	annotationProcessor 'org.projectlombok:lombok'
+}
+
+test {
+	useJUnitPlatform()
+}

spring-boot/argumentresolver/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

spring-boot/argumentresolver/gradlew

@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+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"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+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
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"

spring-boot/argumentresolver/gradlew.bat

@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

spring-boot/argumentresolver/settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'argumentresolver'

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/ArgumentresolverApplication.java

@@ -0,0 +1,13 @@
+package io.reflectoring.argumentresolver;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class ArgumentresolverApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(ArgumentresolverApplication.class, args);
+	}
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/ErrorHandler.java

@@ -0,0 +1,15 @@
+package io.reflectoring.argumentresolver;
+
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.ControllerAdvice;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+
+@ControllerAdvice
+class ErrorHandler {
+
+  @ExceptionHandler(NotFoundException.class)
+  ResponseEntity<?> handleHttpStatusCodeException(NotFoundException e) {
+    return ResponseEntity.status(e.getStatusCode()).build();
+  }
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepository.java

@@ -0,0 +1,12 @@
+package io.reflectoring.argumentresolver;
+
+
+import lombok.Value;
+
+@Value
+class GitRepository {
+
+  private final Long id;
+  private final String slug;
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryArgumentResolver.java

@@ -0,0 +1,43 @@
+package io.reflectoring.argumentresolver;
+
+import java.util.Optional;
+import lombok.RequiredArgsConstructor;
+import org.springframework.core.MethodParameter;
+import org.springframework.web.bind.support.WebDataBinderFactory;
+import org.springframework.web.context.request.NativeWebRequest;
+import org.springframework.web.context.request.ServletWebRequest;
+import org.springframework.web.method.support.HandlerMethodArgumentResolver;
+import org.springframework.web.method.support.ModelAndViewContainer;
+
+@RequiredArgsConstructor
+class GitRepositoryArgumentResolver implements HandlerMethodArgumentResolver {
+
+  private final GitRepositoryFinder gitRepositoryFinder;
+
+  @Override
+  public boolean supportsParameter(MethodParameter parameter) {
+    return parameter.getParameter().getType() == GitRepository.class;
+  }
+
+  @Override
+  public Object resolveArgument(
+      MethodParameter parameter,
+      ModelAndViewContainer mavContainer,
+      NativeWebRequest webRequest,
+      WebDataBinderFactory binderFactory) {
+
+    String requestPath = ((ServletWebRequest) webRequest).getRequest().getPathInfo();
+
+    String slug = requestPath
+        .substring(0, requestPath.indexOf("/", 1))
+        .replaceAll("^/", "");
+
+    Optional<GitRepository> repository = gitRepositoryFinder.findBySlug(slug);
+
+    if (repository.isEmpty()) {
+      throw new NotFoundException();
+    }
+
+    return repository.get();
+  }
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryArgumentResolverConfiguration.java

@@ -0,0 +1,20 @@
+package io.reflectoring.argumentresolver;
+
+import java.util.List;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Component;
+import org.springframework.web.method.support.HandlerMethodArgumentResolver;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+
+@Component
+@RequiredArgsConstructor
+class GitRepositoryArgumentResolverConfiguration implements WebMvcConfigurer {
+
+  private final GitRepositoryFinder gitRepositoryFinder;
+
+  @Override
+  public void addArgumentResolvers(List<HandlerMethodArgumentResolver> resolvers) {
+    resolvers.add(new GitRepositoryArgumentResolver(gitRepositoryFinder));
+  }
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryFinder.java

@@ -0,0 +1,9 @@
+package io.reflectoring.argumentresolver;
+
+import java.util.Optional;
+
+public interface GitRepositoryFinder {
+
+  Optional<GitRepository> findBySlug(String slug);
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryId.java

@@ -0,0 +1,10 @@
+package io.reflectoring.argumentresolver;
+
+import lombok.Value;
+
+@Value
+class GitRepositoryId {
+
+  private final long value;
+
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/GitRepositoryIdConverter.java

@@ -0,0 +1,13 @@
+package io.reflectoring.argumentresolver;
+
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.stereotype.Component;
+
+@Component
+class GitRepositoryIdConverter implements Converter<String, GitRepositoryId> {
+
+  @Override
+  public GitRepositoryId convert(String source) {
+    return new GitRepositoryId(Long.parseLong(source));
+  }
+}

spring-boot/argumentresolver/src/main/java/io/reflectoring/argumentresolver/NotFoundException.java

@@ -0,0 +1,11 @@
+package io.reflectoring.argumentresolver;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.web.client.HttpStatusCodeException;
+
+public class NotFoundException extends HttpStatusCodeException {
+
+  protected NotFoundException() {
+    super(HttpStatus.NOT_FOUND);
+  }
+}

spring-boot/argumentresolver/src/test/java/io/reflectoring/argumentresolver/GitRepositoryArgumentResolverTest.java

@@ -0,0 +1,43 @@
+package io.reflectoring.argumentresolver;
+
+import static org.mockito.BDDMockito.given;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import java.util.Optional;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.test.web.servlet.MockMvc;
+
+@WebMvcTest(controllers = GitRepositoryArgumentResolverTestController.class)
+class GitRepositoryArgumentResolverTest {
+
+  @Autowired
+  private MockMvc mockMvc;
+
+  @MockBean
+  private GitRepositoryFinder gitRepositoryFinder;
+
+  @Test
+  void resolvesSiteSuccessfully() throws Exception {
+
+    given(gitRepositoryFinder.findBySlug("my-repo"))
+        .willReturn(Optional.of(new GitRepository(1L, "my-repo")));
+
+    mockMvc.perform(get("/my-repo/contributors"))
+        .andExpect(status().isOk());
+  }
+
+  @Test
+  void notFoundOnUnknownSlug() throws Exception {
+
+    given(gitRepositoryFinder.findBySlug("unknownSlug"))
+        .willReturn(Optional.empty());
+
+    mockMvc.perform(get("/unknownSlug/contributors"))
+        .andExpect(status().isNotFound());
+  }
+
+}

spring-boot/argumentresolver/src/test/java/io/reflectoring/argumentresolver/GitRepositoryArgumentResolverTestController.java

@@ -0,0 +1,19 @@
+package io.reflectoring.argumentresolver;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping(path = "/{repositorySlug}")
+class GitRepositoryArgumentResolverTestController {
+
+  @GetMapping("/contributors")
+  String listContributors(GitRepository gitRepository) {
+    assertThat(gitRepository.getId()).isEqualTo(1L);
+    return "test";
+  }
+
+}

spring-boot/argumentresolver/src/test/java/io/reflectoring/argumentresolver/GitRepositoryIdConverterTest.java

@@ -0,0 +1,27 @@
+package io.reflectoring.argumentresolver;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.test.web.servlet.MockMvc;
+
+@WebMvcTest(controllers = GitRepositoryIdConverterTestController.class)
+class GitRepositoryIdConverterTest {
+
+  @Autowired
+  private MockMvc mockMvc;
+
+  @MockBean
+  private GitRepositoryFinder gitRepositoryFinder;
+
+  @Test
+  void resolvesRepositoryId() throws Exception {
+    mockMvc.perform(get("/repositories/42"))
+        .andExpect(status().isOk());
+  }
+
+}

spring-boot/argumentresolver/src/test/java/io/reflectoring/argumentresolver/GitRepositoryIdConverterTestController.java

@@ -0,0 +1,18 @@
+package io.reflectoring.argumentresolver;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+class GitRepositoryIdConverterTestController {
+
+  @GetMapping("/repositories/{repositoryId}")
+  String getRepository(@PathVariable("repositoryId") GitRepositoryId gitRepositoryId) {
+    assertThat(gitRepositoryId).isNotNull();
+    return "test";
+  }
+
+}

spring-boot/boundaries/.gitignore

@@ -0,0 +1,32 @@
+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/

spring-boot/boundaries/build.gradle

@@ -0,0 +1,30 @@
+plugins {
+	id 'org.springframework.boot' version '2.2.5.RELEASE'
+	id 'io.spring.dependency-management' version '1.0.9.RELEASE'
+	id 'java'
+}
+
+group = 'io.reflectoring'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '1.8'
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+	implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
+	compileOnly 'org.projectlombok:lombok'
+	runtimeOnly 'com.h2database:h2'
+	annotationProcessor 'org.projectlombok:lombok'
+	testImplementation('org.springframework.boot:spring-boot-starter-test') {
+		exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
+	}
+	// ArchUnit
+	testImplementation 'com.tngtech.archunit:archunit-junit5:0.13.1'
+	testImplementation 'org.reflections:reflections:0.9.10'
+}
+
+test {
+	useJUnitPlatform()
+}

spring-boot/boundaries/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

spring-boot/boundaries/gradlew

@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+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"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+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
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"

spring-boot/boundaries/gradlew.bat

@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

spring-boot/boundaries/settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'boundaries'

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/BoundariesApplication.java

@@ -0,0 +1,13 @@
+package io.reflectoring.boundaries;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class BoundariesApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(BoundariesApplication.class, args);
+	}
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/InternalPackage.java

@@ -0,0 +1,18 @@
+package io.reflectoring.boundaries;
+
+import java.lang.annotation.Documented;
+import java.lang.annotation.ElementType;
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
+
+/**
+ * Annotate a package-info.java file with this annotation to mark it as internal, i.e. no
+ * classes outside of that package may depend on any classes within that package.
+ */
+@Target(ElementType.PACKAGE)
+@Retention(RetentionPolicy.RUNTIME)
+@Documented
+public @interface InternalPackage {
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/api/Invoice.java

@@ -0,0 +1,11 @@
+package io.reflectoring.boundaries.billing.api;
+
+import lombok.Value;
+
+@Value
+public class Invoice {
+
+  private Long userId;
+  private double amount;
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/api/InvoiceCalculator.java

@@ -0,0 +1,9 @@
+package io.reflectoring.boundaries.billing.api;
+
+import java.time.LocalDate;
+
+public interface InvoiceCalculator {
+
+  Invoice calculateInvoice(Long userId, LocalDate fromDate, LocalDate toDate);
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/BillingConfiguration.java

@@ -0,0 +1,10 @@
+package io.reflectoring.boundaries.billing.internal;
+
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@ComponentScan
+class BillingConfiguration {
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/BillingService.java

@@ -0,0 +1,27 @@
+package io.reflectoring.boundaries.billing.internal;
+
+import io.reflectoring.boundaries.billing.api.Invoice;
+import io.reflectoring.boundaries.billing.api.InvoiceCalculator;
+import io.reflectoring.boundaries.billing.internal.database.api.LineItem;
+import io.reflectoring.boundaries.billing.internal.database.api.ReadLineItems;
+import java.time.LocalDate;
+import java.util.List;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Component;
+
+@Component
+@RequiredArgsConstructor
+class BillingService implements InvoiceCalculator {
+
+  private final ReadLineItems readLineItems;
+
+  @Override
+  public Invoice calculateInvoice(Long userId, LocalDate fromDate, LocalDate toDate) {
+    List<LineItem> items = readLineItems.getLineItemsForUser(userId, fromDate, toDate);
+    double sum = items.stream()
+        .mapToDouble(LineItem::getAmount)
+        .sum();
+    return new Invoice(userId, sum);
+  }
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/batchjob/internal/BatchJobConfiguration.java

@@ -0,0 +1,12 @@
+package io.reflectoring.boundaries.billing.internal.batchjob.internal;
+
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.scheduling.annotation.EnableScheduling;
+
+@Configuration
+@EnableScheduling
+@ComponentScan
+class BatchJobConfiguration {
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/batchjob/internal/LoadInvoiceDataBatchJob.java

@@ -0,0 +1,42 @@
+package io.reflectoring.boundaries.billing.internal.batchjob.internal;
+
+import io.reflectoring.boundaries.billing.internal.database.api.WriteLineItems;
+import io.reflectoring.boundaries.billing.internal.database.api.LineItem;
+import java.time.LocalDate;
+import java.util.Arrays;
+import java.util.List;
+import java.util.Random;
+import lombok.RequiredArgsConstructor;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Component;
+
+@RequiredArgsConstructor
+@Component
+class LoadInvoiceDataBatchJob {
+
+  private static final Logger logger = LoggerFactory.getLogger(LoadInvoiceDataBatchJob.class);
+  private static final Random random = new Random();
+  private final WriteLineItems writeLineItems;
+
+  @Scheduled(fixedRate = 5000)
+  void loadDataFromBillingSystem() {
+    List<LineItem> items = getLineItemsFromBillingSystem();
+    writeLineItems.saveLineItems(items);
+  }
+
+  private List<LineItem> getLineItemsFromBillingSystem() {
+    // imagine this list is loaded from a 3rd party system
+    return Arrays.asList(
+        lineItem("bread"),
+        lineItem("butter"),
+        lineItem("toilet paper")
+    );
+  }
+
+  private LineItem lineItem(String itemName) {
+    return new LineItem(42L, itemName, 42.42d, LocalDate.now().minusDays(random.nextInt(10)));
+  }
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/batchjob/internal/package-info.java

@@ -0,0 +1,4 @@
+@InternalPackage
+package io.reflectoring.boundaries.billing.internal.batchjob.internal;
+
+import io.reflectoring.boundaries.InternalPackage;

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/api/LineItem.java

@@ -0,0 +1,14 @@
+package io.reflectoring.boundaries.billing.internal.database.api;
+
+import java.time.LocalDate;
+import lombok.Value;
+
+@Value
+public class LineItem {
+
+  private final Long userId;
+  private final String name;
+  private final double amount;
+  private final LocalDate date;
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/api/ReadLineItems.java

@@ -0,0 +1,10 @@
+package io.reflectoring.boundaries.billing.internal.database.api;
+
+import java.time.LocalDate;
+import java.util.List;
+
+public interface ReadLineItems {
+
+  List<LineItem> getLineItemsForUser(Long userId, LocalDate startDate, LocalDate endDate);
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/api/WriteLineItems.java

@@ -0,0 +1,9 @@
+package io.reflectoring.boundaries.billing.internal.database.api;
+
+import java.util.List;
+
+public interface WriteLineItems {
+
+  void saveLineItems(List<LineItem> lineItems);
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/internal/BillingDatabase.java

@@ -0,0 +1,31 @@
+package io.reflectoring.boundaries.billing.internal.database.internal;
+
+import io.reflectoring.boundaries.billing.internal.database.api.LineItem;
+import io.reflectoring.boundaries.billing.internal.database.api.ReadLineItems;
+import io.reflectoring.boundaries.billing.internal.database.api.WriteLineItems;
+import java.time.LocalDate;
+import java.util.List;
+import java.util.stream.Collectors;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Component;
+
+@Component
+@RequiredArgsConstructor
+class BillingDatabase implements WriteLineItems, ReadLineItems {
+
+  private final LineItemRepository lineItemRepository;
+
+  @Override
+  public void saveLineItems(List<LineItem> lineItems) {
+    for (LineItem lineItem : lineItems) {
+      lineItemRepository.save(LineItemJpaEntity.fromDomainObject(lineItem));
+    }
+  }
+
+  @Override
+  public List<LineItem> getLineItemsForUser(Long userId, LocalDate startDate, LocalDate endDate) {
+    return lineItemRepository.findByUserIdAndDateBetween(userId, startDate, endDate).stream()
+        .map(LineItemJpaEntity::toDomainObject)
+        .collect(Collectors.toList());
+  }
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/internal/BillingDatabaseConfiguration.java

@@ -0,0 +1,12 @@
+package io.reflectoring.boundaries.billing.internal.database.internal;
+
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
+
+@Configuration
+@EnableJpaRepositories
+@ComponentScan
+class BillingDatabaseConfiguration {
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/internal/LineItemJpaEntity.java

@@ -0,0 +1,43 @@
+package io.reflectoring.boundaries.billing.internal.database.internal;
+
+import io.reflectoring.boundaries.billing.internal.database.api.LineItem;
+import java.time.LocalDate;
+import javax.persistence.Entity;
+import javax.persistence.GeneratedValue;
+import javax.persistence.Id;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@Entity
+@Data
+@AllArgsConstructor
+@NoArgsConstructor
+class LineItemJpaEntity {
+
+  @Id
+  @GeneratedValue
+  private Long userId;
+  private String name;
+  private Double amount;
+  private LocalDate date;
+
+  static LineItemJpaEntity fromDomainObject(LineItem lineItem) {
+    return new LineItemJpaEntity(
+        lineItem.getUserId(),
+        lineItem.getName(),
+        lineItem.getAmount(),
+        lineItem.getDate()
+    );
+  }
+
+  LineItem toDomainObject(){
+    return new LineItem(
+        this.userId,
+        this.name,
+        this.amount,
+        this.date
+    );
+  }
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/internal/LineItemRepository.java

@@ -0,0 +1,11 @@
+package io.reflectoring.boundaries.billing.internal.database.internal;
+
+import java.time.LocalDate;
+import java.util.List;
+import org.springframework.data.repository.CrudRepository;
+
+interface LineItemRepository extends CrudRepository<LineItemJpaEntity, Long> {
+
+  List<LineItemJpaEntity> findByUserIdAndDateBetween(Long userId, LocalDate startDate, LocalDate endDate);
+
+}

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/database/internal/package-info.java

@@ -0,0 +1,4 @@
+@InternalPackage
+package io.reflectoring.boundaries.billing.internal.database.internal;
+
+import io.reflectoring.boundaries.InternalPackage;

spring-boot/boundaries/src/main/java/io/reflectoring/boundaries/billing/internal/package-info.java

@@ -0,0 +1,4 @@
+@InternalPackage
+package io.reflectoring.boundaries.billing.internal;
+
+import io.reflectoring.boundaries.InternalPackage;

spring-boot/boundaries/src/test/java/io/reflectoring/boundaries/BoundariesApplicationTests.java

@@ -0,0 +1,13 @@
+package io.reflectoring.boundaries;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class BoundariesApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}

spring-boot/boundaries/src/test/java/io/reflectoring/boundaries/InternalPackageTests.java

@@ -0,0 +1,64 @@
+package io.reflectoring.boundaries;
+
+import static com.tngtech.archunit.lang.syntax.ArchRuleDefinition.noClasses;
+import static org.assertj.core.api.Assertions.assertThat;
+
+import com.tngtech.archunit.core.domain.JavaClasses;
+import com.tngtech.archunit.core.importer.ClassFileImporter;
+import java.io.IOException;
+import java.util.List;
+import java.util.stream.Collectors;
+import org.junit.jupiter.api.Test;
+import org.reflections.Reflections;
+
+/**
+ * Evaluates {@link InternalPackage} annotations and checks that those packages are not accessed from the outside.
+ */
+class InternalPackageTests {
+
+  private static final String BASE_PACKAGE = "io.reflectoring";
+  private final JavaClasses analyzedClasses = new ClassFileImporter().importPackages(BASE_PACKAGE);
+
+  @Test
+  void internalPackagesAreNotAccessedFromOutside() throws IOException {
+
+    // so that the test will break when the base package is re-named
+    assertPackageExists(BASE_PACKAGE);
+
+    List<String> internalPackages = internalPackages(BASE_PACKAGE);
+
+    for (String internalPackage : internalPackages) {
+      assertPackageExists(internalPackage);
+      assertPackageIsNotAccessedFromOutside(internalPackage);
+    }
+
+  }
+
+  /**
+   * Finds all packages annotated with @{@link InternalPackage}.
+   */
+  private List<String> internalPackages(String basePackage) {
+    Reflections reflections = new Reflections(basePackage);
+    return reflections.getTypesAnnotatedWith(InternalPackage.class).stream()
+        .map(c -> c.getPackage().getName())
+        .collect(Collectors.toList());
+  }
+
+  void assertPackageIsNotAccessedFromOutside(String internalPackage) {
+    noClasses().that().resideOutsideOfPackage(packageMatcher(internalPackage))
+        .should().dependOnClassesThat().resideInAPackage(packageMatcher(internalPackage))
+        .check(analyzedClasses);
+  }
+
+  void assertPackageExists(String packageName) {
+    assertThat(analyzedClasses.containPackage(packageName))
+        .as("package %s exists", packageName)
+        .isTrue();
+  }
+
+  private String packageMatcher(String fullyQualifiedPackage) {
+    return fullyQualifiedPackage + "..";
+  }
+
+
+}

spring-boot/data-migration/flyway/.gitignore

@@ -0,0 +1,31 @@
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/

spring-boot/data-migration/flyway/Jenkinsfile-build

@@ -0,0 +1,19 @@
+pipeline {
+	agent any
+
+	stages {
+		checkout scm
+
+		stage('Gradle Build') {
+      steps {
+        script {
+          if (isUnix()) {
+            sh './gradlew clean build --info'
+          } else {
+            bat 'gradlew.bat clean build --info'
+          }
+        }
+      }
+    }
+	}
+}

spring-boot/data-migration/flyway/Jenkinsfile-db-migration

@@ -0,0 +1,19 @@
+pipeline {
+	agent any
+
+	stages {
+		checkout scm
+
+		stage('Apply Database Migrations') {
+      steps {
+        script {
+          if (isUnix()) {
+            sh '/gradlew flywayMigrate --info'
+          } else {
+            bat 'gradlew.bat flywayMigrate --info'
+          }
+        }
+      }
+    }
+	}
+}

spring-boot/data-migration/flyway/build.gradle

@@ -0,0 +1,49 @@
+plugins {
+	id 'org.springframework.boot' version '2.2.3.RELEASE'
+	id 'io.spring.dependency-management' version '1.0.8.RELEASE'
+	id 'java'
+    id "org.flywaydb.flyway" version "6.2.3"
+}
+
+group = 'io.reflectoring'
+version = '0.0.1-SNAPSHOT'
+sourceCompatibility = '11'
+
+repositories {
+	mavenCentral()
+}
+
+dependencies {
+
+	compileOnly 'org.projectlombok:lombok'
+
+    // Spring
+	implementation 'org.springframework.boot:spring-boot-starter-web'
+	implementation 'org.springframework.boot:spring-boot-starter-jdbc'
+
+    // Database
+    implementation 'org.flywaydb:flyway-core'
+	runtimeOnly 'com.h2database:h2'
+
+	// Add jaxb since it's no longer available in Java 11
+	runtime 'javax.xml.bind:jaxb-api:2.3.1'
+
+    // Test
+    testCompile 'org.assertj:assertj-core'
+    testImplementation('org.springframework.boot:spring-boot-starter-test') {
+        exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
+    }
+	testImplementation('org.junit.jupiter:junit-jupiter:5.5.1')
+}
+
+test {
+	useJUnitPlatform()
+}
+
+flyway {
+	url = 'jdbc:h2:mem:'
+	locations = [
+		// Add this if you have Java-based migrations
+		'classpath:db/migration'
+	]
+}

spring-boot/data-migration/flyway/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+#Tue Jan 21 16:55:51 EET 2020
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-all.zip
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStorePath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME

spring-boot/data-migration/flyway/gradlew

@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+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"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+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
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"

spring-boot/data-migration/flyway/gradlew.bat

@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

spring-boot/data-migration/flyway/settings.gradle

@@ -0,0 +1 @@
+rootProject.name = 'flyway'

spring-boot/data-migration/flyway/src/main/java/db/migration/V2__InsertRandomUsers.java

@@ -0,0 +1,23 @@
+package db.migration;
+
+import org.flywaydb.core.api.migration.BaseJavaMigration;
+import org.flywaydb.core.api.migration.Context;
+import org.springframework.jdbc.core.JdbcTemplate;
+import org.springframework.jdbc.datasource.SingleConnectionDataSource;
+
+/**
+ * Example of a Java-based migration using Spring {@link JdbcTemplate}.
+ */
+public class V2__InsertRandomUsers extends BaseJavaMigration {
+
+  public void migrate(Context context) {
+
+    final JdbcTemplate jdbcTemplate = new JdbcTemplate(new SingleConnectionDataSource(context.getConnection(), true));
+
+    // Create 10 random users
+    for (int i = 1; i <= 10; i++) {
+      jdbcTemplate.execute(String.format("insert into test_user(username, first_name, last_name) "
+                                             + "values('%d@reflectoring.io', 'Elvis_%d', 'Presley_%d')", i, i, i));
+    }
+  }
+}

spring-boot/data-migration/flyway/src/main/java/io/reflectoring/flyway/FlywayApplication.java

@@ -0,0 +1,12 @@
+package io.reflectoring.flyway;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class FlywayApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(FlywayApplication.class, args);
+	}
+}

spring-boot/data-migration/flyway/src/main/resources/db/migration/U1__Undo_Init.sql

@@ -0,0 +1 @@
+DROP TABLE test_user;

spring-boot/data-migration/flyway/src/main/resources/db/migration/V1__Init.sql

@@ -0,0 +1,9 @@
+-- Init script
+
+-- DDL
+CREATE TABLE test_user(
+    id INT AUTO_INCREMENT PRIMARY KEY,
+    username VARCHAR(255) NOT NULL UNIQUE,
+    first_name VARCHAR(255) NOT NULL,
+    last_name VARCHAR(255) NOT NULL
+);

spring-boot/data-migration/flyway/src/test/java/io/reflectoring/flyway/FlywayWithH2Test.java

@@ -0,0 +1,43 @@
+package io.reflectoring.flyway;
+
+import java.util.List;
+import org.assertj.core.api.Assertions;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
+import org.springframework.jdbc.core.JdbcTemplate;
+
+@DataJpaTest
+class FlywayWithH2Test {
+
+  @Autowired
+  private JdbcTemplate jdbcTemplate;
+
+  @Test
+  void databaseHasBeenInitialized() {
+
+    jdbcTemplate.execute("insert into test_user (username, first_name, last_name) values('reflectoring', 'Elvis', 'Presley')");
+
+    final List<AuthUser> authUsers = jdbcTemplate
+        .query("SELECT username, first_name, last_name FROM test_user", (rs, rowNum) -> new AuthUser(
+            rs.getString("username"),
+            rs.getString("first_name"),
+            rs.getString("last_name")
+        ));
+
+    Assertions.assertThat(authUsers).isNotEmpty();
+  }
+
+  private static class AuthUser {
+    public String username;
+    public String firstName;
+    public String lastName;
+
+    public AuthUser(final String username, final String firstName, final String lastName) {
+
+      this.username = username;
+      this.firstName = firstName;
+      this.lastName = lastName;
+    }
+  }
+}

spring-boot/password-encoding/.gitignore

@@ -0,0 +1,32 @@
+HELP.md
+.gradle
+build/
+!gradle/wrapper/gradle-wrapper.jar
+!**/src/main/**
+!**/src/test/**
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+out/
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+
+### VS Code ###
+.vscode/

spring-boot/password-encoding/build.gradle

@@ -0,0 +1,41 @@
+plugins {
+    id 'org.springframework.boot' version '2.2.2.RELEASE'
+    id 'io.spring.dependency-management' version '1.0.8.RELEASE'
+    id 'java'
+}
+
+group = 'io.reflectoring'
+version = '0.0.1-SNAPSHOT'
+description = 'password-encoding-spring-boot'
+sourceCompatibility = '11'
+
+
+repositories {
+    mavenCentral()
+}
+
+configurations {
+    compileOnly {
+        extendsFrom annotationProcessor
+    }
+}
+
+dependencies {
+    implementation 'org.springframework.boot:spring-boot-starter-security:2.2.4.RELEASE'
+    implementation 'org.springframework.boot:spring-boot-starter-web:2.2.4.RELEASE'
+    implementation 'org.springframework.boot:spring-boot-starter-data-jpa:2.2.4.RELEASE'
+    implementation 'com.h2database:h2:1.4.200'
+    implementation 'org.flywaydb:flyway-core:6.0.8'
+    implementation 'org.bouncycastle:bcprov-jdk15on:1.64'
+    implementation 'org.projectlombok:lombok:1.18.12'
+    annotationProcessor 'org.projectlombok:lombok'
+    annotationProcessor 'org.springframework.boot:spring-boot-configuration-processor'
+    implementation 'com.google.guava:guava:28.2-jre'
+    testImplementation 'org.springframework.boot:spring-boot-starter-test:2.2.4.RELEASE'
+    testImplementation 'org.springframework.security:spring-security-test:5.2.1.RELEASE'
+}
+
+
+test {
+    useJUnitPlatform()
+}

spring-boot/password-encoding/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

spring-boot/password-encoding/gradlew

@@ -0,0 +1,183 @@
+#!/usr/bin/env sh
+
+#
+# Copyright 2015 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.
+#
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+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"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn () {
+    echo "$*"
+}
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+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
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if [ "$cygwin" = "true" -o "$msys" = "true" ] ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=`expr $i + 1`
+    done
+    case $i in
+        0) set -- ;;
+        1) set -- "$args0" ;;
+        2) set -- "$args0" "$args1" ;;
+        3) set -- "$args0" "$args1" "$args2" ;;
+        4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save () {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=`save "$@"`
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+exec "$JAVACMD" "$@"

spring-boot/password-encoding/gradlew.bat

@@ -0,0 +1,100 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem 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, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/PasswordEncodingSpringBootApplication.java

@@ -0,0 +1,12 @@
+package io.reflectoring.passwordencoding;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class PasswordEncodingSpringBootApplication {
+
+  public static void main(String[] args) {
+    SpringApplication.run(PasswordEncodingSpringBootApplication.class, args);
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/authentication/DatabaseUserDetailPasswordService.java

@@ -0,0 +1,28 @@
+package io.reflectoring.passwordencoding.authentication;
+
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UserDetailsPasswordService;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Transactional
+@Service
+public class DatabaseUserDetailPasswordService implements UserDetailsPasswordService {
+
+  private final UserRepository userRepository;
+
+  private final UserDetailsMapper userDetailsMapper;
+
+  public DatabaseUserDetailPasswordService(
+      UserRepository userRepository, UserDetailsMapper userDetailsMapper) {
+    this.userRepository = userRepository;
+    this.userDetailsMapper = userDetailsMapper;
+  }
+
+  @Override
+  public UserDetails updatePassword(UserDetails user, String newPassword) {
+    UserCredentials userCredentials = userRepository.findByUsername(user.getUsername());
+    userCredentials.setPassword(newPassword);
+    return userDetailsMapper.toUserDetails(userCredentials);
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/authentication/DatabaseUserDetailsService.java

@@ -0,0 +1,29 @@
+package io.reflectoring.passwordencoding.authentication;
+
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.core.userdetails.UserDetailsService;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Service
+@Transactional
+public class DatabaseUserDetailsService implements UserDetailsService {
+
+  private final UserRepository userRepository;
+
+  private final UserDetailsMapper userDetailsMapper;
+
+  public DatabaseUserDetailsService(
+      UserRepository userRepository, UserDetailsMapper userDetailsMapper) {
+    this.userRepository = userRepository;
+    this.userDetailsMapper = userDetailsMapper;
+  }
+
+  @Override
+  public UserDetails loadUserByUsername(String username)
+          throws UsernameNotFoundException {
+    UserCredentials userCredentials = userRepository.findByUsername(username);
+    return userDetailsMapper.toUserDetails(userCredentials);
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/authentication/UserCredentials.java

@@ -0,0 +1,31 @@
+package io.reflectoring.passwordencoding.authentication;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+import javax.persistence.*;
+import java.util.Set;
+
+@Entity
+@Data
+@NoArgsConstructor
+@AllArgsConstructor
+@Builder
+@Table(name = "users")
+public class UserCredentials {
+
+  @Id private String username;
+
+  private String password;
+
+  boolean enabled;
+
+  @ElementCollection
+  @JoinTable(
+      name = "authorities",
+      joinColumns = {@JoinColumn(name = "username")})
+  @Column(name = "authority")
+  private Set<String> roles;
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/authentication/UserDetailsMapper.java

@@ -0,0 +1,17 @@
+package io.reflectoring.passwordencoding.authentication;
+
+import org.springframework.security.core.userdetails.User;
+import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.stereotype.Component;
+
+@Component
+class UserDetailsMapper {
+
+  UserDetails toUserDetails(UserCredentials userCredentials) {
+
+    return User.withUsername(userCredentials.getUsername())
+        .password(userCredentials.getPassword())
+        .roles(userCredentials.getRoles().toArray(String[]::new))
+        .build();
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/authentication/UserRepository.java

@@ -0,0 +1,10 @@
+package io.reflectoring.passwordencoding.authentication;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.transaction.annotation.Transactional;
+
+@Transactional
+public interface UserRepository extends JpaRepository<UserCredentials, String> {
+
+  UserCredentials findByUsername(String username);
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/configuration/SecurityConfiguration.java

@@ -0,0 +1,82 @@
+package io.reflectoring.passwordencoding.configuration;
+
+import io.reflectoring.passwordencoding.authentication.DatabaseUserDetailPasswordService;
+import io.reflectoring.passwordencoding.authentication.DatabaseUserDetailsService;
+import io.reflectoring.passwordencoding.workfactor.BcCryptWorkFactorService;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.security.authentication.AuthenticationProvider;
+import org.springframework.security.authentication.dao.DaoAuthenticationProvider;
+import org.springframework.security.config.annotation.web.builders.HttpSecurity;
+import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
+import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;
+import org.springframework.security.crypto.argon2.Argon2PasswordEncoder;
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+import org.springframework.security.crypto.password.*;
+import org.springframework.security.crypto.scrypt.SCryptPasswordEncoder;
+
+import java.util.HashMap;
+import java.util.Map;
+
+@Configuration
+@EnableWebSecurity
+class SecurityConfiguration extends WebSecurityConfigurerAdapter {
+
+  private final BcCryptWorkFactorService bcCryptWorkFactorService;
+  private final DatabaseUserDetailsService databaseUserDetailsService;
+  private final DatabaseUserDetailPasswordService databaseUserDetailPasswordService;
+
+  public SecurityConfiguration(
+          BcCryptWorkFactorService bcCryptWorkFactorService,
+          DatabaseUserDetailsService databaseUserDetailsService,
+          DatabaseUserDetailPasswordService databaseUserDetailPasswordService) {
+    this.bcCryptWorkFactorService = bcCryptWorkFactorService;
+    this.databaseUserDetailsService = databaseUserDetailsService;
+    this.databaseUserDetailPasswordService = databaseUserDetailPasswordService;
+  }
+
+  @Override
+  protected void configure(HttpSecurity httpSecurity) throws Exception {
+    httpSecurity
+        .csrf()
+        .disable()
+        .authorizeRequests()
+        .antMatchers("/registration")
+        .permitAll()
+        .anyRequest()
+        .authenticated()
+        .and()
+        .httpBasic();
+
+    httpSecurity.headers().frameOptions().disable();
+  }
+
+  @Bean
+  public PasswordEncoder passwordEncoder() {
+    // we must use deprecated encoder to support their encoding
+    String encodingId = "bcrypt";
+    Map<String, PasswordEncoder> encoders = new HashMap<>();
+    encoders.put(encodingId, new BCryptPasswordEncoder(bcCryptWorkFactorService.calculateStrength()));
+    encoders.put("ldap", new LdapShaPasswordEncoder());
+    encoders.put("MD4", new Md4PasswordEncoder());
+    encoders.put("MD5", new MessageDigestPasswordEncoder("MD5"));
+    encoders.put("noop", NoOpPasswordEncoder.getInstance());
+    encoders.put("pbkdf2", new Pbkdf2PasswordEncoder());
+    encoders.put("scrypt", new SCryptPasswordEncoder());
+    encoders.put("SHA-1", new MessageDigestPasswordEncoder("SHA-1"));
+    encoders.put("SHA-256", new MessageDigestPasswordEncoder("SHA-256"));
+    encoders.put("sha256", new StandardPasswordEncoder());
+    encoders.put("argon2", new Argon2PasswordEncoder());
+
+    return new DelegatingPasswordEncoder(encodingId, encoders);
+  }
+
+  @Bean
+  public AuthenticationProvider daoAuthenticationProvider() {
+    DaoAuthenticationProvider provider = new DaoAuthenticationProvider();
+    provider.setPasswordEncoder(passwordEncoder());
+    provider.setUserDetailsPasswordService(this.databaseUserDetailPasswordService);
+    provider.setUserDetailsService(this.databaseUserDetailsService);
+    return provider;
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/encoder/Argon2Example.java

@@ -0,0 +1,18 @@
+package io.reflectoring.passwordencoding.encoder;
+
+import org.springframework.security.crypto.argon2.Argon2PasswordEncoder;
+
+class Argon2Example {
+
+  public String encode(String plainPassword) {
+    int saltLength = 16; // salt length in bytes
+    int hashLength = 32; // hash length in bytes
+    int parallelism = 1; // currently is not supported
+    int memory = 4096; // memory costs
+    int iterations = 3;
+
+    Argon2PasswordEncoder argon2PasswordEncoder =
+        new Argon2PasswordEncoder(saltLength, hashLength, parallelism, memory, iterations);
+    return argon2PasswordEncoder.encode(plainPassword);
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/encoder/BCryptExample.java

@@ -0,0 +1,15 @@
+package io.reflectoring.passwordencoding.encoder;
+
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+
+import java.security.SecureRandom;
+
+class BCryptExample {
+
+  public String encode(String plainPassword) {
+    int strength = 10;
+    BCryptPasswordEncoder bCryptPasswordEncoder =
+        new BCryptPasswordEncoder(strength, new SecureRandom());
+    return bCryptPasswordEncoder.encode(plainPassword);
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/encoder/Pbkdf2Example.java

@@ -0,0 +1,17 @@
+package io.reflectoring.passwordencoding.encoder;
+
+import org.springframework.security.crypto.password.Pbkdf2PasswordEncoder;
+
+class Pbkdf2Example {
+
+  public String encode(String plainPassword) {
+
+    String pepper = "pepper"; // secret key used by password encoding
+    int iterations = 200000; // number of hash iteration
+    int hashWidth = 256; // hash with in bits
+
+    Pbkdf2PasswordEncoder pbkdf2PasswordEncoder =
+        new Pbkdf2PasswordEncoder(pepper, iterations, hashWidth);
+    return pbkdf2PasswordEncoder.encode(plainPassword);
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/encoder/SCryptExample.java

@@ -0,0 +1,18 @@
+package io.reflectoring.passwordencoding.encoder;
+
+import org.springframework.security.crypto.scrypt.SCryptPasswordEncoder;
+
+class SCryptExample {
+
+  public String encode(String plainPassword) {
+    int cpuCost = (int) Math.pow(2, 14); // factor to increase CPU costs
+    int memoryCost = 8; // factor to increases memory usage
+    int parallelization = 1; // currently  nor supported by Spring Security
+    int keyLength = 32; // key length in bytes
+    int saltLength = 64; // salt length in bytes
+
+    SCryptPasswordEncoder sCryptPasswordEncoder =
+        new SCryptPasswordEncoder(cpuCost, memoryCost, parallelization, keyLength, saltLength);
+    return sCryptPasswordEncoder.encode(plainPassword);
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/resources/Car.java

@@ -0,0 +1,16 @@
+package io.reflectoring.passwordencoding.resources;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@NoArgsConstructor
+@Data
+@Builder
+@AllArgsConstructor
+class Car {
+
+  private String name;
+  private String color;
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/resources/CarResources.java

@@ -0,0 +1,15 @@
+package io.reflectoring.passwordencoding.resources;
+
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.Set;
+
+@RestController
+class CarResources {
+
+  @GetMapping("/cars")
+  public Set<Car> cars() {
+    return Set.of(new Car("vw", "black"), new Car("bmw", "white"));
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/resources/RegistrationResource.java

@@ -0,0 +1,37 @@
+package io.reflectoring.passwordencoding.resources;
+
+import io.reflectoring.passwordencoding.authentication.UserCredentials;
+import io.reflectoring.passwordencoding.authentication.UserRepository;
+import org.springframework.http.HttpStatus;
+import org.springframework.security.crypto.password.PasswordEncoder;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.ResponseStatus;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.Set;
+
+@RestController
+class RegistrationResource {
+
+  private final UserRepository userRepository;
+  private final PasswordEncoder passwordEncoder;
+
+  public RegistrationResource(UserRepository userRepository, PasswordEncoder passwordEncoder) {
+    this.userRepository = userRepository;
+    this.passwordEncoder = passwordEncoder;
+  }
+
+  @PostMapping("/registration")
+  @ResponseStatus(code = HttpStatus.CREATED)
+  public void register(@RequestBody UserCredentialsDto userCredentialsDto) {
+    UserCredentials user =
+        UserCredentials.builder()
+            .enabled(true)
+            .username(userCredentialsDto.getUsername())
+            .password(passwordEncoder.encode(userCredentialsDto.getPassword()))
+            .roles(Set.of("USER"))
+            .build();
+    userRepository.save(user);
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/resources/UserCredentialsDto.java

@@ -0,0 +1,15 @@
+package io.reflectoring.passwordencoding.resources;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@Data
+@Builder
+@AllArgsConstructor
+@NoArgsConstructor
+class UserCredentialsDto {
+  private String username;
+  private String password;
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/workfactor/BcCryptWorkFactorService.java

@@ -0,0 +1,101 @@
+package io.reflectoring.passwordencoding.workfactor;
+
+import com.google.common.base.Stopwatch;
+import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+import org.springframework.stereotype.Component;
+
+import java.util.concurrent.TimeUnit;
+
+@Component
+public class BcCryptWorkFactorService {
+
+  private static final String TEST_PASSWORD = "my password";
+  private static final int GOAL_MILLISECONDS_PER_PASSWORD = 1000;
+  private static final int MIN_STRENGTH = 4;
+  private static final int MAX_STRENGTH = 31;
+
+  /**
+   * Calculates the strength (a.k.a. log rounds) for the BCrypt Algorithm, so that password encoding
+   * takes about 1s. This method uses the divide-and-conquer algorithm.
+   */
+  public BcryptWorkFactor calculateStrengthDivideAndConquer() {
+    return calculateStrengthDivideAndConquer(
+        new BcryptWorkFactor(MIN_STRENGTH, Integer.MIN_VALUE),
+        new BcryptWorkFactor(MAX_STRENGTH, Integer.MAX_VALUE));
+  }
+
+  private BcryptWorkFactor calculateStrengthDivideAndConquer(
+      BcryptWorkFactor smallFactor, BcryptWorkFactor bigFactor) {
+    if (bigFactor.getStrength() - smallFactor.getStrength() == 1) {
+      return getClosestStrength(smallFactor, bigFactor);
+    }
+    int midStrength =
+        (bigFactor.getStrength() - smallFactor.getStrength()) / 2 + smallFactor.getStrength();
+    long duration = calculateDuration(midStrength);
+    BcryptWorkFactor midFactor = new BcryptWorkFactor(midStrength, duration);
+    if (duration < GOAL_MILLISECONDS_PER_PASSWORD) {
+      return calculateStrengthDivideAndConquer(midFactor, bigFactor);
+    }
+    return calculateStrengthDivideAndConquer(smallFactor, midFactor);
+  }
+
+  private BcryptWorkFactor getClosestStrength(
+      BcryptWorkFactor smallFactor, BcryptWorkFactor bigFactor) {
+    if (isPreviousDurationCloserToGoal(smallFactor.getDuration(), bigFactor.getDuration())) {
+      return smallFactor;
+    }
+    return bigFactor;
+  }
+
+  private long calculateDuration(int strength) {
+    BCryptPasswordEncoder bCryptPasswordEncoder = new BCryptPasswordEncoder(strength);
+    Stopwatch stopwatch = Stopwatch.createStarted();
+    bCryptPasswordEncoder.encode(TEST_PASSWORD);
+    stopwatch.stop();
+    return stopwatch.elapsed(TimeUnit.MILLISECONDS);
+  }
+
+  /**
+   * Calculates the strength (a.k.a. log rounds) for the BCrypt Algorithm, so that password encoding
+   * takes about 1s. This method iterates over strength from 4 to 31 and calculates the duration of
+   * password encoding for every value of strength. It returns the first strength, that takes more
+   * than 1s
+   */
+  public int calculateStrength() {
+    for (int strength = MIN_STRENGTH; strength <= MAX_STRENGTH; strength++) {
+
+      long duration = calculateDuration(strength);
+      if (duration >= GOAL_MILLISECONDS_PER_PASSWORD) {
+        return strength;
+      }
+    }
+    throw new RuntimeException(
+        String.format(
+            "Could not find suitable round number for bcrypt encoding. The encoding with %d rounds"
+                + " takes less than %d ms.",
+            MAX_STRENGTH, GOAL_MILLISECONDS_PER_PASSWORD));
+  }
+
+  /**
+   * @param previousDuration duration from previous iteration
+   * @param currentDuration duration of current iteration
+   * @param strength current strength
+   * @return return the current strength, if current duration is closer to
+   *     GOAL_MILLISECONDS_PER_PASSWORD, otherwise current strength-1.
+   */
+  int getStrength(long previousDuration, long currentDuration, int strength) {
+    if (isPreviousDurationCloserToGoal(previousDuration, currentDuration)) {
+      return strength - 1;
+    } else {
+      return strength;
+    }
+  }
+
+  /**
+   * return true, if previousDuration is closer to the goal than currentDuration, false otherwise.
+   */
+  boolean isPreviousDurationCloserToGoal(long previousDuration, long currentDuration) {
+    return Math.abs(GOAL_MILLISECONDS_PER_PASSWORD - previousDuration)
+        < Math.abs(GOAL_MILLISECONDS_PER_PASSWORD - currentDuration);
+  }
+}

spring-boot/password-encoding/src/main/java/io/reflectoring/passwordencoding/workfactor/BcryptWorkFactor.java

@@ -0,0 +1,12 @@
+package io.reflectoring.passwordencoding.workfactor;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+
+@Data
+@AllArgsConstructor
+class BcryptWorkFactor {
+
+  private int strength;
+  private long duration;
+}