Merge branch 'master' into itsLucario/master

Example code for resilience4j retry

.github/workflows/ci.yml

@@ -0,0 +1,16 @@
+name: CI
+
+on: [push]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - name: "Checkout sources"
+      uses: actions/checkout@v1
+    - name: "Setup Java"
+      uses: actions/setup-java@v1
+      with:
+        java-version: 13
+    - name: "Build all modules"
+      run: chmod 755 build-all.sh && ./build-all.sh

.travis.yml

@@ -15,4 +15,4 @@ script:
 language: java
 
 jdk:
-  - oraclejdk11
+  - oraclejdk13

README.md

@@ -1,6 +1,6 @@
 # Example Code Repository
 
-[![Travis CI Status](https://travis-ci.org/thombergs/code-examples.svg?branch=master)](https://travis-ci.org/thombergs/code-examples)
+[![CI](https://github.com/thombergs/code-examples/workflows/CI/badge.svg)](https://github.com/thombergs/code-examples/actions?query=workflow%3ACI)
 
 This repo contains example projects which show how to use different (not only) Java technologies.
 The examples are usually accompanied by a blog post on [https://reflectoring.io](https://reflectoring.io).

aws/aws-hello-world/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

aws/aws-hello-world/src/main/java/io/reflectoring/awshelloworld/HelloWorldController.java

@@ -8,7 +8,7 @@ public class HelloWorldController {
 
   @GetMapping("/hello")
   public String helloWorld(){
-    return "Hello AWS!";
+    return "Hello AWS (v4)!";
   }
 
 }

aws/aws-rds-hello-world/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

aws/cloudformation/ecs-zero-downtime-deployment/README.md

@@ -0,0 +1,8 @@
+# Overview
+
+![ECS Zero Downtime Deployment](ecs-in-two-public-subnets.svg)
+
+# Companion Blog Post
+
+[The AWS Journey Part 4: Zero-Downtime Deployment with CloudFormation and ECS](https://reflectoring.io/aws-cloudformation-ecs-deployment/)
+

aws/cloudformation/ecs-zero-downtime-deployment/create-change-set.sh

@@ -0,0 +1,18 @@
+# Turning off the AWS pager so that the CLI doesn't open an editor for each command result
+export AWS_PAGER=""
+
+aws cloudformation create-change-set \
+  --change-set-name update-reflectoring-ecs-zero-downtime-deployment-service \
+  --stack-name reflectoring-ecs-zero-downtime-deployment-service \
+  --use-previous-template \
+  --parameters \
+      ParameterKey=StackName,ParameterValue=reflectoring-ecs-zero-downtime-deployment-network \
+      ParameterKey=ServiceName,ParameterValue=reflectoring-hello-world \
+      ParameterKey=ImageUrl,ParameterValue=docker.io/reflectoring/aws-hello-world:v4 \
+      ParameterKey=ContainerPort,ParameterValue=8080 \
+      ParameterKey=HealthCheckPath,ParameterValue=/hello \
+      ParameterKey=HealthCheckIntervalSeconds,ParameterValue=90
+
+aws cloudformation describe-change-set \
+  --stack-name reflectoring-ecs-zero-downtime-deployment-service \
+  --change-set-name update-reflectoring-ecs-zero-downtime-deployment-service

aws/cloudformation/ecs-zero-downtime-deployment/create.sh

@@ -0,0 +1,22 @@
+# Turning off the AWS pager so that the CLI doesn't open an editor for each command result
+export AWS_PAGER=""
+
+aws cloudformation create-stack \
+  --stack-name reflectoring-ecs-zero-downtime-deployment-network \
+  --template-body file://network.yml \
+  --capabilities CAPABILITY_IAM
+
+aws cloudformation wait stack-create-complete --stack-name reflectoring-ecs-zero-downtime-deployment-network
+
+aws cloudformation create-stack \
+  --stack-name reflectoring-ecs-zero-downtime-deployment-service \
+  --template-body file://service.yml \
+  --parameters \
+      ParameterKey=StackName,ParameterValue=reflectoring-ecs-zero-downtime-deployment-network \
+      ParameterKey=ServiceName,ParameterValue=reflectoring-hello-world \
+      ParameterKey=ImageUrl,ParameterValue=docker.io/reflectoring/aws-hello-world:v3 \
+      ParameterKey=ContainerPort,ParameterValue=8080 \
+      ParameterKey=HealthCheckPath,ParameterValue=/hello \
+      ParameterKey=HealthCheckIntervalSeconds,ParameterValue=90
+
+aws cloudformation wait stack-create-complete --stack-name reflectoring-ecs-zero-downtime-deployment-service

aws/cloudformation/ecs-zero-downtime-deployment/delete.sh

@@ -0,0 +1,8 @@
+# Turning off the AWS pager so that the CLI doesn't open an editor for each command result
+export AWS_PAGER=""
+
+aws cloudformation delete-stack --stack-name reflectoring-ecs-zero-downtime-deployment-service
+aws cloudformation wait stack-delete-complete --stack-name reflectoring-ecs-zero-downtime-deployment-service
+
+aws cloudformation delete-stack --stack-name reflectoring-ecs-zero-downtime-deployment-network
+aws cloudformation wait stack-delete-complete --stack-name reflectoring-ecs-zero-downtime-deployment-network

aws/cloudformation/ecs-zero-downtime-deployment/ecs-in-two-public-subnets.drawio

@@ -0,0 +1 @@
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aws/cloudformation/ecs-zero-downtime-deployment/execute-change-set.sh

@@ -0,0 +1,8 @@
+# Turning off the AWS pager so that the CLI doesn't open an editor for each command result
+export AWS_PAGER=""
+
+aws cloudformation execute-change-set \
+  --stack-name reflectoring-ecs-zero-downtime-deployment-service \
+  --change-set-name update-reflectoring-ecs-zero-downtime-deployment-service
+
+aws cloudformation wait stack-update-complete --stack-name reflectoring-ecs-zero-downtime-deployment-service

aws/cloudformation/ecs-zero-downtime-deployment/network.yml

@@ -0,0 +1,247 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Description: A network stack for deploying containers in AWS ECS.
+  This stack creates a VPC with two public subnets and a loadbalancer to balance traffic between those subnets.
+  Derived from a template at https://github.com/nathanpeck/aws-cloudformation-fargate.
+Resources:
+
+  VPC:
+    Type: AWS::EC2::VPC
+    Properties:
+      CidrBlock: '10.0.0.0/16'
+
+  PublicSubnetOne:
+    Type: AWS::EC2::Subnet
+    Properties:
+      AvailabilityZone:
+        Fn::Select:
+          - 0
+          - Fn::GetAZs: {Ref: 'AWS::Region'}
+      VpcId: !Ref 'VPC'
+      CidrBlock: '10.0.1.0/24'
+      MapPublicIpOnLaunch: true
+
+  PublicSubnetTwo:
+    Type: AWS::EC2::Subnet
+    Properties:
+      AvailabilityZone:
+        Fn::Select:
+          - 1
+          - Fn::GetAZs: {Ref: 'AWS::Region'}
+      VpcId: !Ref 'VPC'
+      CidrBlock: '10.0.2.0/24'
+      MapPublicIpOnLaunch: true
+
+  InternetGateway:
+    Type: AWS::EC2::InternetGateway
+
+  GatewayAttachement:
+    Type: AWS::EC2::VPCGatewayAttachment
+    Properties:
+      VpcId: !Ref 'VPC'
+      InternetGatewayId: !Ref 'InternetGateway'
+
+  PublicRouteTable:
+    Type: AWS::EC2::RouteTable
+    Properties:
+      VpcId: !Ref 'VPC'
+
+  PublicSubnetOneRouteTableAssociation:
+    Type: AWS::EC2::SubnetRouteTableAssociation
+    Properties:
+      SubnetId: !Ref PublicSubnetOne
+      RouteTableId: !Ref PublicRouteTable
+
+  PublicSubnetTwoRouteTableAssociation:
+    Type: AWS::EC2::SubnetRouteTableAssociation
+    Properties:
+      SubnetId: !Ref PublicSubnetTwo
+      RouteTableId: !Ref PublicRouteTable
+
+  PublicRoute:
+    Type: AWS::EC2::Route
+    DependsOn: GatewayAttachement
+    Properties:
+      RouteTableId: !Ref 'PublicRouteTable'
+      DestinationCidrBlock: '0.0.0.0/0'
+      GatewayId: !Ref 'InternetGateway'
+
+  PublicLoadBalancerSecurityGroup:
+    Type: AWS::EC2::SecurityGroup
+    Properties:
+      GroupDescription: Access to the public facing load balancer
+      VpcId: !Ref 'VPC'
+      SecurityGroupIngress:
+        # Allow access to ALB from anywhere on the internet
+        - CidrIp: 0.0.0.0/0
+          IpProtocol: -1
+
+  PublicLoadBalancer:
+    Type: AWS::ElasticLoadBalancingV2::LoadBalancer
+    Properties:
+      Scheme: internet-facing
+      Subnets:
+        # The load balancer is placed into the public subnets, so that traffic
+        # from the internet can reach the load balancer directly via the internet gateway
+        - !Ref PublicSubnetOne
+        - !Ref PublicSubnetTwo
+      SecurityGroups: [!Ref 'PublicLoadBalancerSecurityGroup']
+
+  DummyTargetGroupPublic:
+    Type: AWS::ElasticLoadBalancingV2::TargetGroup
+    Properties:
+      HealthCheckIntervalSeconds: 6
+      HealthCheckPath: /
+      HealthCheckProtocol: HTTP
+      HealthCheckTimeoutSeconds: 5
+      HealthyThresholdCount: 2
+      Name: "no-op"
+      Port: 80
+      Protocol: HTTP
+      UnhealthyThresholdCount: 2
+      VpcId: !Ref 'VPC'
+
+  PublicLoadBalancerListener:
+    Type: AWS::ElasticLoadBalancingV2::Listener
+    DependsOn:
+      - PublicLoadBalancer
+    Properties:
+      DefaultActions:
+        - TargetGroupArn: !Ref 'DummyTargetGroupPublic'
+          Type: 'forward'
+      LoadBalancerArn: !Ref 'PublicLoadBalancer'
+      Port: 80
+      Protocol: HTTP
+
+  ECSCluster:
+    Type: AWS::ECS::Cluster
+
+  ECSSecurityGroup:
+    Type: AWS::EC2::SecurityGroup
+    Properties:
+      GroupDescription: Access to the ECS containers
+      VpcId: !Ref 'VPC'
+
+  ECSSecurityGroupIngressFromPublicALB:
+    Type: AWS::EC2::SecurityGroupIngress
+    Properties:
+      Description: Ingress from the public ALB
+      GroupId: !Ref 'ECSSecurityGroup'
+      IpProtocol: -1
+      SourceSecurityGroupId: !Ref 'PublicLoadBalancerSecurityGroup'
+
+  ECSSecurityGroupIngressFromSelf:
+    Type: AWS::EC2::SecurityGroupIngress
+    Properties:
+      Description: Ingress from other containers in the same security group
+      GroupId: !Ref 'ECSSecurityGroup'
+      IpProtocol: -1
+      SourceSecurityGroupId: !Ref 'ECSSecurityGroup'
+
+  ECSRole:
+    Type: AWS::IAM::Role
+    Properties:
+      AssumeRolePolicyDocument:
+        Statement:
+          - Effect: Allow
+            Principal:
+              Service: [ecs.amazonaws.com]
+            Action: ['sts:AssumeRole']
+      Path: /
+      Policies:
+        - PolicyName: ecs-service
+          PolicyDocument:
+            Statement:
+              - Effect: Allow
+                Action:
+                  # Rules which allow ECS to attach network interfaces to instances
+                  # on your behalf in order for awsvpc networking mode to work right
+                  - 'ec2:AttachNetworkInterface'
+                  - 'ec2:CreateNetworkInterface'
+                  - 'ec2:CreateNetworkInterfacePermission'
+                  - 'ec2:DeleteNetworkInterface'
+                  - 'ec2:DeleteNetworkInterfacePermission'
+                  - 'ec2:Describe*'
+                  - 'ec2:DetachNetworkInterface'
+
+                  # Rules which allow ECS to update load balancers on your behalf
+                  # with the information sabout how to send traffic to your containers
+                  - 'elasticloadbalancing:DeregisterInstancesFromLoadBalancer'
+                  - 'elasticloadbalancing:DeregisterTargets'
+                  - 'elasticloadbalancing:Describe*'
+                  - 'elasticloadbalancing:RegisterInstancesWithLoadBalancer'
+                  - 'elasticloadbalancing:RegisterTargets'
+                Resource: '*'
+
+  ECSTaskExecutionRole:
+    Type: AWS::IAM::Role
+    Properties:
+      AssumeRolePolicyDocument:
+        Statement:
+          - Effect: Allow
+            Principal:
+              Service: [ecs-tasks.amazonaws.com]
+            Action: ['sts:AssumeRole']
+      Path: /
+      Policies:
+        - PolicyName: AmazonECSTaskExecutionRolePolicy
+          PolicyDocument:
+            Statement:
+              - Effect: Allow
+                Action:
+                  # Allow the ECS Tasks to download images from ECR
+                  - 'ecr:GetAuthorizationToken'
+                  - 'ecr:BatchCheckLayerAvailability'
+                  - 'ecr:GetDownloadUrlForLayer'
+                  - 'ecr:BatchGetImage'
+
+                  # Allow the ECS tasks to upload logs to CloudWatch
+                  - 'logs:CreateLogStream'
+                  - 'logs:PutLogEvents'
+                Resource: '*'
+
+Outputs:
+  ClusterName:
+    Description: The name of the ECS cluster
+    Value: !Ref 'ECSCluster'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ClusterName' ] ]
+  ExternalUrl:
+    Description: The url of the external load balancer
+    Value: !Join ['', ['http://', !GetAtt 'PublicLoadBalancer.DNSName']]
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ExternalUrl' ] ]
+  ECSRole:
+    Description: The ARN of the ECS role
+    Value: !GetAtt 'ECSRole.Arn'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ECSRole' ] ]
+  ECSTaskExecutionRole:
+    Description: The ARN of the ECS role
+    Value: !GetAtt 'ECSTaskExecutionRole.Arn'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ECSTaskExecutionRole' ] ]
+  PublicListener:
+    Description: The ARN of the public load balancer's Listener
+    Value: !Ref PublicLoadBalancerListener
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PublicListener' ] ]
+  VPCId:
+    Description: The ID of the VPC that this stack is deployed in
+    Value: !Ref 'VPC'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'VPCId' ] ]
+  PublicSubnetOne:
+    Description: Public subnet one
+    Value: !Ref 'PublicSubnetOne'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PublicSubnetOne' ] ]
+  PublicSubnetTwo:
+    Description: Public subnet two
+    Value: !Ref 'PublicSubnetTwo'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'PublicSubnetTwo' ] ]
+  ECSSecurityGroup:
+    Description: A security group used to allow ECS containers to receive traffic
+    Value: !Ref 'ECSSecurityGroup'
+    Export:
+      Name: !Join [ ':', [ !Ref 'AWS::StackName', 'ECSSecurityGroup' ] ]

aws/cloudformation/ecs-zero-downtime-deployment/service.yml

@@ -0,0 +1,139 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Description: Deploy a service on AWS Fargate, hosted in two public subnets and accessible via a public load balancer.
+  Derived from a template at https://github.com/nathanpeck/aws-cloudformation-fargate.
+Parameters:
+  StackName:
+    Type: String
+    Description: The name of the networking stack that
+      these resources are put into.
+  ServiceName:
+    Type: String
+    Description: A human-readable name for the service.
+  HealthCheckPath:
+    Type: String
+    Default: /health
+    Description: Path to perform the healthcheck on each instance.
+  HealthCheckIntervalSeconds:
+    Type: Number
+    Default: 5
+    Description: Number of seconds to wait between each health check.
+  ImageUrl:
+    Type: String
+    Description: The url of a docker image that will handle incoming traffic.
+  ContainerPort:
+    Type: Number
+    Default: 80
+    Description: The port number the application inside the docker container
+      is binding to.
+  ContainerCpu:
+    Type: Number
+    Default: 256
+    Description: How much CPU to give the container. 1024 is 1 CPU.
+  ContainerMemory:
+    Type: Number
+    Default: 512
+    Description: How much memory in megabytes to give the container.
+  Path:
+    Type: String
+    Default: "*"
+    Description: A path on the public load balancer that this service
+      should be connected to.
+  DesiredCount:
+    Type: Number
+    Default: 2
+    Description: How many copies of the service task to run.
+
+Resources:
+
+  TargetGroup:
+    Type: AWS::ElasticLoadBalancingV2::TargetGroup
+    Properties:
+      HealthCheckIntervalSeconds: !Ref 'HealthCheckIntervalSeconds'
+      HealthCheckPath: !Ref 'HealthCheckPath'
+      HealthCheckProtocol: HTTP
+      HealthCheckTimeoutSeconds: 5
+      HealthyThresholdCount: 2
+      TargetType: ip
+      Name: !Ref 'ServiceName'
+      Port: !Ref 'ContainerPort'
+      Protocol: HTTP
+      UnhealthyThresholdCount: 2
+      VpcId:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'VPCId']]
+
+  LoadBalancerRule:
+    Type: AWS::ElasticLoadBalancingV2::ListenerRule
+    Properties:
+      Actions:
+        - TargetGroupArn: !Ref 'TargetGroup'
+          Type: 'forward'
+      Conditions:
+        - Field: path-pattern
+          Values: [!Ref 'Path']
+      ListenerArn:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'PublicListener']]
+      Priority: 1
+
+  LogGroup:
+    Type: AWS::Logs::LogGroup
+    Properties:
+      LogGroupName: !Ref 'ServiceName'
+      RetentionInDays: 1
+
+  TaskDefinition:
+    Type: AWS::ECS::TaskDefinition
+    Properties:
+      Family: !Ref 'ServiceName'
+      Cpu: !Ref 'ContainerCpu'
+      Memory: !Ref 'ContainerMemory'
+      NetworkMode: awsvpc
+      RequiresCompatibilities:
+        - FARGATE
+      ExecutionRoleArn:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'ECSTaskExecutionRole']]
+      ContainerDefinitions:
+        - Name: !Ref 'ServiceName'
+          Cpu: !Ref 'ContainerCpu'
+          Memory: !Ref 'ContainerMemory'
+          Image: !Ref 'ImageUrl'
+          PortMappings:
+            - ContainerPort: !Ref 'ContainerPort'
+          LogConfiguration:
+            LogDriver: 'awslogs'
+            Options:
+              awslogs-group: !Ref 'ServiceName'
+              awslogs-region: !Ref AWS::Region
+              awslogs-stream-prefix: !Ref 'ServiceName'
+
+  Service:
+    Type: AWS::ECS::Service
+    DependsOn: LoadBalancerRule
+    Properties:
+      ServiceName: !Ref 'ServiceName'
+      Cluster:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'ClusterName']]
+      LaunchType: FARGATE
+      DeploymentConfiguration:
+        MaximumPercent: 200
+        MinimumHealthyPercent: 50
+      DesiredCount: !Ref 'DesiredCount'
+      NetworkConfiguration:
+        AwsvpcConfiguration:
+          AssignPublicIp: ENABLED
+          SecurityGroups:
+            - Fn::ImportValue:
+                !Join [':', [!Ref 'StackName', 'ECSSecurityGroup']]
+          Subnets:
+            - Fn::ImportValue:
+                !Join [':', [!Ref 'StackName', 'PublicSubnetOne']]
+            - Fn::ImportValue:
+                !Join [':', [!Ref 'StackName', 'PublicSubnetTwo']]
+      TaskDefinition: !Ref 'TaskDefinition'
+      LoadBalancers:
+        - ContainerName: !Ref 'ServiceName'
+          ContainerPort: !Ref 'ContainerPort'
+          TargetGroupArn: !Ref 'TargetGroup'

aws/cloudformation/ecs-zero-downtime-deployment/task.yml

@@ -0,0 +1,109 @@
+AWSTemplateFormatVersion: '2010-09-09'
+Description: Deploy a service on AWS Fargate, hosted in two public subnets and accessible via a public load balancer.
+  Derived from a template at https://github.com/nathanpeck/aws-cloudformation-fargate.
+Parameters:
+  StackName:
+    Type: String
+    Description: The name of the networking stack that
+      these resources are put into.
+  ServiceName:
+    Type: String
+    Description: A human-readable name for the service.
+  HealthCheckPath:
+    Type: String
+    Default: /health
+    Description: Path to perform the healthcheck on each instance.
+  HealthCheckIntervalSeconds:
+    Type: Number
+    Default: 5
+    Description: Number of seconds to wait between each health check.
+  ImageUrl:
+    Type: String
+    Description: The url of a docker image that will handle incoming traffic.
+  ContainerPort:
+    Type: Number
+    Default: 80
+    Description: The port number the application inside the docker container
+      is binding to.
+  ContainerCpu:
+    Type: Number
+    Default: 256
+    Description: How much CPU to give the container. 1024 is 1 CPU.
+  ContainerMemory:
+    Type: Number
+    Default: 512
+    Description: How much memory in megabytes to give the container.
+  Path:
+    Type: String
+    Default: "*"
+    Description: A path on the public load balancer that this service
+      should be connected to.
+  DesiredCount:
+    Type: Number
+    Default: 2
+    Description: How many copies of the service task to run.
+
+Resources:
+
+  TargetGroup:
+    Type: AWS::ElasticLoadBalancingV2::TargetGroup
+    Properties:
+      HealthCheckIntervalSeconds: !Ref 'HealthCheckIntervalSeconds'
+      HealthCheckPath: !Ref 'HealthCheckPath'
+      HealthCheckProtocol: HTTP
+      HealthCheckTimeoutSeconds: 5
+      HealthyThresholdCount: 2
+      TargetType: ip
+      Name: !Ref 'ServiceName'
+      Port: !Ref 'ContainerPort'
+      Protocol: HTTP
+      UnhealthyThresholdCount: 2
+      VpcId:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'VPCId']]
+
+  LoadBalancerRule:
+    Type: AWS::ElasticLoadBalancingV2::ListenerRule
+    Properties:
+      Actions:
+        - TargetGroupArn: !Ref 'TargetGroup'
+          Type: 'forward'
+      Conditions:
+        - Field: path-pattern
+          Values: [!Ref 'Path']
+      ListenerArn:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'PublicListener']]
+      Priority: 1
+
+  LogGroup:
+    Type: AWS::Logs::LogGroup
+    Properties:
+      LogGroupName: !Ref 'ServiceName'
+      RetentionInDays: 1
+
+  TaskDefinition:
+    Type: AWS::ECS::TaskDefinition
+    Properties:
+      Family: !Ref 'ServiceName'
+      Cpu: !Ref 'ContainerCpu'
+      Memory: !Ref 'ContainerMemory'
+      NetworkMode: awsvpc
+      RequiresCompatibilities:
+        - FARGATE
+      ExecutionRoleArn:
+        Fn::ImportValue:
+          !Join [':', [!Ref 'StackName', 'ECSTaskExecutionRole']]
+      ContainerDefinitions:
+        - Name: !Ref 'ServiceName'
+          Cpu: !Ref 'ContainerCpu'
+          Memory: !Ref 'ContainerMemory'
+          Image: !Ref 'ImageUrl'
+          PortMappings:
+            - ContainerPort: !Ref 'ContainerPort'
+          LogConfiguration:
+            LogDriver: 'awslogs'
+            Options:
+              awslogs-group: !Ref 'ServiceName'
+              awslogs-region: !Ref AWS::Region
+              awslogs-stream-prefix: !Ref 'ServiceName'

aws/cloudformation/ecs-zero-downtime-deployment/update.sh

@@ -0,0 +1,17 @@
+# Turning off the AWS pager so that the CLI doesn't open an editor for each command result
+export AWS_PAGER=""
+
+IMAGE_URL=$1
+
+aws cloudformation update-stack \
+  --stack-name reflectoring-ecs-zero-downtime-deployment-service \
+  --use-previous-template \
+  --parameters \
+      ParameterKey=StackName,ParameterValue=reflectoring-ecs-zero-downtime-deployment-network \
+      ParameterKey=ServiceName,ParameterValue=reflectoring-hello-world \
+      ParameterKey=ImageUrl,ParameterValue=$IMAGE_URL \
+      ParameterKey=ContainerPort,ParameterValue=8080 \
+      ParameterKey=HealthCheckPath,ParameterValue=/hello \
+      ParameterKey=HealthCheckIntervalSeconds,ParameterValue=90
+
+aws cloudformation wait stack-update-complete --stack-name reflectoring-ecs-zero-downtime-deployment-service

aws/cloudformation/rds-in-private-subnet/README.md

@@ -4,4 +4,4 @@
 
 # Companion Blog Post
 
-TO DO
+[The AWS Journey Part 3: Connecting a Spring Boot Application to an RDS Instance with CloudFormation](https://reflectoring.io/aws-cloudformation-rds/)

build-all.sh

@@ -28,6 +28,33 @@ build_gradle_module() {
   }
 }
 
+run_gradle_task() {
+  MODULE_PATH=$1
+  TASK_NAME=$2
+  echo ""
+  echo "+++"
+  echo "+++ RUNNING GRADLE TASK $MODULE_PATH : $TASK_NAME"
+  echo "+++"
+  cd $MODULE_PATH && {
+    chmod +x gradlew
+    ./gradlew $TASK_NAME
+    if [ $? -ne 0 ]
+    then
+      echo ""
+      echo "+++"
+      echo "+++ GRADLE TASK $MODULE_PATH : $TASK_NAME FAILED"
+      echo "+++"
+      exit 1
+    else
+      echo ""
+      echo "+++"
+      echo "+++ GRADLE TASK $MODULE_PATH : $TASK_NAME SUCCESSFUL"
+      echo "+++"
+    fi
+    cd $MAIN_DIR
+  }
+}
+
 build_maven_module() {
   MODULE_PATH=$1
   echo ""
@@ -54,6 +81,12 @@ build_maven_module() {
   }
 }
 
+build_maven_module "spring-boot/spring-boot-kafka"
+build_maven_module "resilience4j/retry"
+build_maven_module "solid/lsp"
+run_gradle_task "spring-boot/thymeleaf-vue" "npmInstall"
+build_gradle_module "spring-boot/thymeleaf-vue"
+build_gradle_module "spring-boot/spring-boot-springdoc"
 build_maven_module "spring-boot/dependency-injection"
 build_maven_module "spring-boot/spring-boot-openapi"
 build_maven_module "spring-boot/data-migration/liquibase"
@@ -86,6 +119,9 @@ build_gradle_module "spring-boot/validation"
 build_gradle_module "spring-boot/profiles"
 build_gradle_module "spring-boot/password-encoding"
 build_gradle_module "spring-boot/testcontainers"
+build_gradle_module "spring-boot/hazelcast/hazelcast-embedded-cache"
+build_gradle_module "spring-boot/hazelcast/hazelcast-client-server"
+build_gradle_module "spring-boot/cache"
 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"
@@ -98,4 +134,4 @@ build_gradle_module "tools/jacoco"
 echo ""
 echo "+++"
 echo "+++ ALL MODULES SUCCESSFUL"
-echo "+++"
+echo "+++"

junit/assumptions/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.6.4-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip

logging/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ 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
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip

pact/pact-feign-consumer/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ 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
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip

pact/pact-message-consumer/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-5.6.4-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip

pact/pact-message-producer/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ 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
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip

pact/pact-spring-provider/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ 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
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip

patterns/build.gradle

@@ -16,7 +16,8 @@ repositories {
 }
 
 dependencies {
-	compileOnly 'org.projectlombok:lombok:1.18.2'
+	compileOnly 'org.projectlombok:lombok:1.18.6'
+	annotationProcessor 'org.projectlombok:lombok:1.18.6'
 	implementation 'javax.validation:validation-api:2.0.1.Final'
 	runtimeOnly 'org.hibernate:hibernate-validator:6.0.17.Final'
 	testRuntimeOnly 'org.hibernate:hibernate-validator:6.0.17.Final'

patterns/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ 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
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip

reactive/gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

resilience4j/retry/.mvn/wrapper/MavenWrapperDownloader.java

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

resilience4j/retry/.mvn/wrapper/maven-wrapper.properties

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

resilience4j/retry/Readme.md

@@ -0,0 +1 @@
+Run the Examples program

resilience4j/retry/mvnw

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

resilience4j/retry/mvnw.cmd

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

resilience4j/retry/pom.xml

@@ -0,0 +1,115 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>io.reflectoring.resilience4j.retry</groupId>
+  <artifactId>retry</artifactId>
+  <version>1.0-SNAPSHOT</version>
+
+  <name>retry</name>
+  <url>http://www.reflectoring.io</url>
+
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <maven.compiler.source>1.8</maven.compiler.source>
+    <maven.compiler.target>1.8</maven.compiler.target>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>4.11</version>
+      <scope>test</scope>
+    </dependency>
+
+    <!-- https://mvnrepository.com/artifact/io.github.resilience4j/resilience4j-retry -->
+    <dependency>
+      <groupId>io.github.resilience4j</groupId>
+      <artifactId>resilience4j-retry</artifactId>
+      <version>1.5.0</version>
+    </dependency>
+
+    <!-- https://mvnrepository.com/artifact/io.github.resilience4j/resilience4j-core -->
+    <dependency>
+      <groupId>io.github.resilience4j</groupId>
+      <artifactId>resilience4j-core</artifactId>
+      <version>1.5.0</version>
+    </dependency>
+
+    <dependency>
+      <groupId>io.github.resilience4j</groupId>
+      <artifactId>resilience4j-all</artifactId>
+      <version>1.5.0</version>
+    </dependency>
+
+    <dependency>
+      <groupId>org.projectlombok</groupId>
+      <artifactId>lombok</artifactId>
+      <version>1.18.12</version>
+    </dependency>
+
+    <!-- https://mvnrepository.com/artifact/io.github.resilience4j/resilience4j-micrometer -->
+    <dependency>
+      <groupId>io.github.resilience4j</groupId>
+      <artifactId>resilience4j-micrometer</artifactId>
+      <version>1.5.0</version>
+    </dependency>
+
+    <!-- https://mvnrepository.com/artifact/io.micrometer/micrometer-core -->
+    <dependency>
+      <groupId>io.micrometer</groupId>
+      <artifactId>micrometer-core</artifactId>
+      <version>1.5.0</version>
+    </dependency>
+
+  </dependencies>
+
+  <build>
+    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
+      <plugins>
+        <!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
+        <plugin>
+          <artifactId>maven-clean-plugin</artifactId>
+          <version>3.1.0</version>
+        </plugin>
+        <!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
+        <plugin>
+          <artifactId>maven-resources-plugin</artifactId>
+          <version>3.0.2</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-compiler-plugin</artifactId>
+          <version>3.8.0</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-surefire-plugin</artifactId>
+          <version>2.22.1</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-jar-plugin</artifactId>
+          <version>3.0.2</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-install-plugin</artifactId>
+          <version>2.5.2</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-deploy-plugin</artifactId>
+          <version>2.8.2</version>
+        </plugin>
+        <!-- site lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
+        <plugin>
+          <artifactId>maven-site-plugin</artifactId>
+          <version>3.7.1</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-project-info-reports-plugin</artifactId>
+          <version>3.0.0</version>
+        </plugin>
+      </plugins>
+    </pluginManagement>
+  </build>
+</project>

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/Examples.java

@@ -0,0 +1,350 @@
+package io.reflectoring.resilience4j.retry;
+
+import static java.time.temporal.ChronoUnit.SECONDS;
+
+import io.github.resilience4j.core.IntervalFunction;
+import io.github.resilience4j.micrometer.tagged.TaggedRetryMetrics;
+import io.github.resilience4j.retry.Retry;
+import io.github.resilience4j.retry.RetryConfig;
+import io.github.resilience4j.retry.RetryRegistry;
+import io.micrometer.core.instrument.Meter;
+import io.micrometer.core.instrument.MeterRegistry;
+import io.micrometer.core.instrument.simple.SimpleMeterRegistry;
+import io.reflectoring.resilience4j.retry.exceptions.FlightServiceBaseException;
+import io.reflectoring.resilience4j.retry.exceptions.RateLimitExceededException;
+import io.reflectoring.resilience4j.retry.exceptions.SeatsUnavailableException;
+import io.reflectoring.resilience4j.retry.model.BookingRequest;
+import io.reflectoring.resilience4j.retry.model.BookingResponse;
+import io.reflectoring.resilience4j.retry.model.Flight;
+import io.reflectoring.resilience4j.retry.model.SearchRequest;
+import io.reflectoring.resilience4j.retry.model.SearchResponse;
+import io.reflectoring.resilience4j.retry.services.FlightBookingService;
+import io.reflectoring.resilience4j.retry.services.FlightSearchService;
+import io.reflectoring.resilience4j.retry.services.failures.FailHalfTheTime;
+import io.reflectoring.resilience4j.retry.services.failures.FailNTimes;
+import io.reflectoring.resilience4j.retry.services.failures.RateLimitFailNTimes;
+import io.vavr.CheckedFunction0;
+import java.time.Duration;
+import java.util.Collections;
+import java.util.List;
+import java.util.UUID;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionStage;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.function.Consumer;
+import java.util.function.Predicate;
+import java.util.function.Supplier;
+import java.util.stream.StreamSupport;
+
+public class Examples {
+
+    void generalUsagePattern() {
+        RetryConfig config = RetryConfig.ofDefaults(); // ----> 1
+        RetryRegistry registry = RetryRegistry.of(config); // ----> 2
+        Retry retry = registry.retry("flightSearchService", config); // ----> 3
+
+        FlightSearchService service = new FlightSearchService();
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+        Supplier<List<Flight>> flightSearchSupplier = () -> service.searchFlights(request); // ----> 4
+
+        Supplier<List<Flight>> retryingFlightSearch = Retry.decorateSupplier(retry, flightSearchSupplier); // ----> 5
+
+        System.out.println(retryingFlightSearch.get()); // ----> 6
+    }
+
+    void basicExample() {
+        RetryConfig config = RetryConfig.custom().maxAttempts(3).waitDuration(Duration.of(2, SECONDS)).build();
+        RetryRegistry registry = RetryRegistry.of(config);
+        Retry retry = registry.retry("flightSearchService", config);
+
+        FlightSearchService service = new FlightSearchService();
+        service.setPotentialFailure(new FailNTimes(1));
+
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+        Supplier<List<Flight>> flightSearchSupplier = () -> service.searchFlights(request);
+
+        Supplier<List<Flight>> retryingFlightSearch = Retry.decorateSupplier(retry, flightSearchSupplier);
+        System.out.println(retryingFlightSearch.get());
+    }
+
+    void basicExample_ServiceThrowingException_v1() {
+        RetryConfig config = RetryConfig.custom().maxAttempts(3).build();
+        RetryRegistry registry = RetryRegistry.of(config);
+        Retry retry = registry.retry("flightSearchService", config);
+
+        FlightSearchService service = new FlightSearchService();
+        service.setPotentialFailure(new FailNTimes(1));
+
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+        Supplier<List<Flight>> flightSearchSupplier = () -> {
+            try {
+                return service.searchFlightsThrowingException(request);
+            } catch (Exception e) {
+                // handle exception
+            }
+            return Collections.emptyList();
+        };
+
+        Supplier<List<Flight>> retryingFlightSearch = Retry.decorateSupplier(retry, flightSearchSupplier);
+        System.out.println(retryingFlightSearch.get());
+    }
+
+    void basicExample_ServiceThrowingException_v2() {
+        RetryConfig config = RetryConfig.custom().maxAttempts(3).build();
+        RetryRegistry registry = RetryRegistry.of(config);
+        Retry retry = registry.retry("flightSearchService", config);
+
+        FlightSearchService service = new FlightSearchService();
+        service.setPotentialFailure(new FailNTimes(1));
+
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+        CheckedFunction0<List<Flight>> retryingFlightSearch = Retry.decorateCheckedSupplier(retry, () -> service.searchFlightsThrowingException(request));
+
+        try {
+            System.out.println(retryingFlightSearch.apply());
+        } catch (Throwable throwable) {
+            // handle exception
+        }
+    }
+
+    void predicateExample() {
+        RetryConfig config = RetryConfig.<SearchResponse>custom().
+                                            maxAttempts(3).
+                                            waitDuration(Duration.of(3, SECONDS)).
+                                            retryOnResult(searchResponse -> searchResponse.getErrorCode().equals("FS-167")).
+                                            build();
+        RetryRegistry registry = RetryRegistry.of(config);
+        Retry retry = registry.retry("flightSearchService", config);
+
+        FlightSearchService service = new FlightSearchService();
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+        CheckedFunction0<SearchResponse> retryingFlightSearch = Retry.decorateCheckedSupplier(retry, () -> service.httpSearchFlights(request));
+        SearchResponse response;
+        try {
+           response = retryingFlightSearch.apply();
+           System.out.println(response);
+        } catch (Throwable throwable) {
+            // handle exception
+        }
+    }
+
+    void retryExceptionsIgnoreExceptionsExample() {
+        RetryConfig config = RetryConfig.custom().
+                maxAttempts(3).
+                waitDuration(Duration.of(3, SECONDS)).
+                retryExceptions(FlightServiceBaseException.class).
+                ignoreExceptions(SeatsUnavailableException.class).
+                build();
+        RetryRegistry registry = RetryRegistry.of(config);
+        Retry retry = registry.retry("flightBookService", config);
+
+        FlightBookingService service = new FlightBookingService();
+        System.out.println("Example to illustrate: rate limit runtime exception - will be retried");
+        // rate limit exception
+        service.setPotentialFailure(new RateLimitFailNTimes(2));
+        Flight flight = new Flight("XY 213", "07/30/2020", "NYC", "LAX");
+        BookingRequest request = new BookingRequest(UUID.randomUUID().toString(), flight, 2, "C");
+        Supplier<BookingResponse> bookingResponseSupplier = () -> service.bookFlight(request);
+        Supplier<BookingResponse> bookingResponse = Retry.decorateSupplier(retry, bookingResponseSupplier);
+
+        try {
+            System.out.println(bookingResponse.get());
+        }
+        catch (RateLimitExceededException rle) {
+            rle.printStackTrace();
+        }
+
+        System.out.println("Example to illustrate: no seats available runtime exception will not be retried");
+        // seats not available checked exception
+        FlightBookingService service2 = new FlightBookingService();
+        Flight flight2 = new Flight("XY 765", "07/30/2020", "NYC", "LAX");
+        BookingRequest request2 = new BookingRequest(UUID.randomUUID().toString(), flight2, 2, "C");
+        CheckedFunction0<BookingResponse> bookingResponseSupplier2 = () -> service2.bookFlight(request2);
+        CheckedFunction0<BookingResponse> bookingResponse2 = Retry.decorateCheckedSupplier(retry, bookingResponseSupplier2);
+
+        try {
+            System.out.println(bookingResponse2.apply());
+        }
+        catch (Throwable e) {
+            e.printStackTrace();
+        }
+    }
+
+    void intervalFunction_Random() {
+        RetryConfig config = RetryConfig.custom().
+                                        maxAttempts(4).
+                                        intervalFunction(IntervalFunction.ofRandomized(2000)).
+                                        build();
+        RetryRegistry registry = RetryRegistry.of(config);
+        Retry retry = registry.retry("flightSearchService", config);
+
+        FlightSearchService service = new FlightSearchService();
+        service.setPotentialFailure(new FailNTimes(3));
+
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+        Supplier<List<Flight>> flightSearchSupplier = () -> service.searchFlights(request);
+
+        Supplier<List<Flight>> retryingFlightSearch = Retry.decorateSupplier(retry, flightSearchSupplier);
+        System.out.println(retryingFlightSearch.get());
+    }
+
+    void intervalFunction_Exponential() {
+        RetryConfig config = RetryConfig.custom().
+                                            maxAttempts(6).
+                                            intervalFunction(IntervalFunction.ofExponentialBackoff(1000, 2)).
+                                            build();
+        RetryRegistry registry = RetryRegistry.of(config);
+        Retry retry = registry.retry("flightSearchService", config);
+
+        FlightSearchService service = new FlightSearchService();
+        service.setPotentialFailure(new FailNTimes(5));
+
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+        Supplier<List<Flight>> flightSearchSupplier = () -> service.searchFlights(request);
+
+        Supplier<List<Flight>> retryingFlightSearch = Retry.decorateSupplier(retry, flightSearchSupplier);
+        System.out.println(retryingFlightSearch.get());
+    }
+
+    void asyncRetryExample()  {
+        FlightSearchService service = new FlightSearchService();
+        service.setPotentialFailure(new FailNTimes(4));
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+
+        RetryConfig config = RetryConfig.custom().maxAttempts(5).waitDuration(Duration.of(1, SECONDS)).build();
+        RetryRegistry registry = RetryRegistry.of(config);
+        Retry retry = registry.retry("flightSearchService", config);
+
+        ScheduledExecutorService scheduler = Executors.newSingleThreadScheduledExecutor();
+        Supplier<CompletionStage<List<Flight>>> completionStageSupplier = () -> CompletableFuture.supplyAsync(() -> service.searchFlights(request));
+        retry.executeCompletionStage(scheduler, completionStageSupplier).thenAccept(System.out::println);
+
+        // Sleep a few seconds to let the other thread complete
+        try {
+            Thread.sleep(10000);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+        scheduler.shutdown();
+    }
+
+    void retryEventsExample() {
+        RetryConfig config = RetryConfig.custom().maxAttempts(3).waitDuration(Duration.of(1, SECONDS)).build();
+        RetryRegistry registry = RetryRegistry.of(config);
+        Retry retry = registry.retry("flightSearchService", config);
+
+        Retry.EventPublisher publisher = retry.getEventPublisher();
+        publisher.onRetry(event -> System.out.println(event.toString()));
+        publisher.onSuccess(event -> System.out.println(event.toString()));
+
+        FlightSearchService service = new FlightSearchService();
+        service.setPotentialFailure(new RateLimitFailNTimes(2));
+
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+        List<Flight> flights = retry.executeSupplier(() -> service.searchFlights(request));
+        System.out.println(flights);
+    }
+
+    void retryOnException() {
+        Predicate<Throwable> rateLimitPredicate = rle -> (rle instanceof  RateLimitExceededException)
+                                                                && "RL-101".equals(((RateLimitExceededException) rle).getErrorCode());
+        RetryConfig config = RetryConfig.custom().
+                                            maxAttempts(3).
+                                            waitDuration(Duration.of(1, SECONDS)).
+                                            retryOnException(rateLimitPredicate).
+                                            build();
+        RetryRegistry registry = RetryRegistry.of(config);
+        Retry retry = registry.retry("flightSearchService", config);
+
+        FlightSearchService service = new FlightSearchService();
+        service.setPotentialFailure(new RateLimitFailNTimes(2));
+
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+        List<Flight> flights = retry.executeSupplier(() -> service.searchFlights(request));
+        System.out.println(flights);
+    }
+
+    void retryMetrics() {
+        RetryConfig config = RetryConfig.custom().maxAttempts(3).build();
+        RetryRegistry retryRegistry = RetryRegistry.of(config);
+        Retry retry = retryRegistry.retry("flightSearchService", config);
+
+        MeterRegistry meterRegistry = new SimpleMeterRegistry();
+        TaggedRetryMetrics.ofRetryRegistry(retryRegistry).bindTo(meterRegistry);
+
+        FlightSearchService service = new FlightSearchService();
+
+        SearchRequest request = new SearchRequest("NYC", "LAX", "07/31/2020");
+        Supplier<List<Flight>> flights = Retry.decorateSupplier(retry, () -> service.searchFlights(request));
+
+        for (int i=0; i<10; i++) {
+            service.setPotentialFailure(new FailHalfTheTime(2));
+            System.out.println(flights.get());
+        }
+
+        Consumer<Meter> meterConsumer = meter -> {
+            String desc = meter.getId().getDescription();
+            String metricName = meter.getId().getTag("kind");
+            Double metricValue = StreamSupport.stream(meter.measure().spliterator(), false).
+                                                filter(m -> m.getStatistic().name().equals("COUNT")).
+                                                findFirst().
+                                                map(m -> m.getValue()).
+                                                orElse(0.0);
+            System.out.println(desc + " - " + metricName + ": " + metricValue);
+        };
+        meterRegistry.forEachMeter(meterConsumer);
+    }
+
+    public static void main(String[] args) {
+        Examples examples = new Examples();
+
+        System.out.println("------------------------ generalUsagePattern ----------------------------------------------");
+        examples.generalUsagePattern();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("------------------------- basicExample ---------------------------------------------");
+        examples.basicExample();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("------------------------- basicExample_ServiceThrowingException_v1 ---------------------------------------------");
+        examples.basicExample_ServiceThrowingException_v1();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("-------------------------- basicExample_ServiceThrowingException_v2 --------------------------------------------");
+        examples.basicExample_ServiceThrowingException_v2();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("--------------------------- predicateExample -------------------------------------------");
+        examples.predicateExample();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("---------------------------- retryExceptionsIgnoreExceptionsExample ------------------------------------------");
+        examples.retryExceptionsIgnoreExceptionsExample();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("---------------------------- intervalFunction_Random ------------------------------------------");
+        examples.intervalFunction_Random();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("----------------------------- intervalFunction_Exponential -----------------------------------------");
+        examples.intervalFunction_Exponential();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("----------------------------- asyncRetryExample -----------------------------------------");
+        examples.asyncRetryExample();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("----------------------------- retryEventsExample -----------------------------------------");
+        examples.retryEventsExample();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("------------------------------ retryOnException ----------------------------------------");
+        examples.retryOnException();
+        System.out.println("----------------------------------------------------------------------");
+
+        System.out.println("------------------------------- retryMetrics ---------------------------------------");
+        examples.retryMetrics();
+        System.out.println("----------------------------------------------------------------------");
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/exceptions/FlightServiceBaseException.java

@@ -0,0 +1,7 @@
+package io.reflectoring.resilience4j.retry.exceptions;
+
+public class FlightServiceBaseException extends RuntimeException {
+    public FlightServiceBaseException(String message) {
+        super(message);
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/exceptions/RateLimitExceededException.java

@@ -0,0 +1,14 @@
+package io.reflectoring.resilience4j.retry.exceptions;
+
+public class RateLimitExceededException extends FlightServiceBaseException {
+    String errorCode;
+
+    public RateLimitExceededException(String message, String errorCode) {
+        super(message);
+        this.errorCode = errorCode;
+    }
+
+    public String getErrorCode() {
+        return errorCode;
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/exceptions/SeatsUnavailableException.java

@@ -0,0 +1,7 @@
+package io.reflectoring.resilience4j.retry.exceptions;
+
+public class SeatsUnavailableException extends FlightServiceBaseException {
+    public SeatsUnavailableException(String message) {
+        super(message);
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/model/BookingRequest.java

@@ -0,0 +1,47 @@
+package io.reflectoring.resilience4j.retry.model;
+
+public class BookingRequest {
+    String requestId;
+    Flight flight;
+    int seatCount;
+    String seatClass;
+
+    public BookingRequest(String requestId, Flight flight, int seatCount, String seatClass) {
+        this.requestId = requestId;
+        this.flight = flight;
+        this.seatCount = seatCount;
+        this.seatClass = seatClass;
+    }
+
+    public String getRequestId() {
+        return requestId;
+    }
+
+    public void setRequestId(String requestId) {
+        this.requestId = requestId;
+    }
+
+    public Flight getFlight() {
+        return flight;
+    }
+
+    public void setFlight(Flight flight) {
+        this.flight = flight;
+    }
+
+    public int getSeatCount() {
+        return seatCount;
+    }
+
+    public void setSeatCount(int seatCount) {
+        this.seatCount = seatCount;
+    }
+
+    public String getSeatClass() {
+        return seatClass;
+    }
+
+    public void setSeatClass(String seatClass) {
+        this.seatClass = seatClass;
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/model/BookingResponse.java

@@ -0,0 +1,24 @@
+package io.reflectoring.resilience4j.retry.model;
+
+public class BookingResponse {
+    String status;
+
+    public BookingResponse(String status) {
+        this.status = status;
+    }
+
+    public String getStatus() {
+        return status;
+    }
+
+    public void setStatus(String status) {
+        this.status = status;
+    }
+
+    @Override
+    public String toString() {
+        return "BookingResponse{" +
+                "status='" + status + '\'' +
+                '}';
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/model/Flight.java

@@ -0,0 +1,60 @@
+package io.reflectoring.resilience4j.retry.model;
+
+public class Flight {
+    String flightNumber;
+    String flightDate;
+    String from;
+    String to;
+
+    public Flight() {
+    }
+
+    public Flight(String flightNumber, String flightDate, String from, String to) {
+        this.flightNumber = flightNumber;
+        this.flightDate = flightDate;
+        this.from = from;
+        this.to = to;
+    }
+
+    public String getFlightNumber() {
+        return flightNumber;
+    }
+
+    public void setFlightNumber(String flightNumber) {
+        this.flightNumber = flightNumber;
+    }
+
+    public String getFlightDate() {
+        return flightDate;
+    }
+
+    public void setFlightDate(String flightDate) {
+        this.flightDate = flightDate;
+    }
+
+    public String getFrom() {
+        return from;
+    }
+
+    public void setFrom(String from) {
+        this.from = from;
+    }
+
+    public String getTo() {
+        return to;
+    }
+
+    public void setTo(String to) {
+        this.to = to;
+    }
+
+    @Override
+    public String toString() {
+        return "Flight{" +
+                "flightNumber='" + flightNumber + '\'' +
+                ", flightDate='" + flightDate + '\'' +
+                ", from='" + from + '\'' +
+                ", to='" + to + '\'' +
+                '}';
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/model/SearchRequest.java

@@ -0,0 +1,25 @@
+package io.reflectoring.resilience4j.retry.model;
+
+public class SearchRequest {
+    String from;
+    String to;
+    String flightDate;
+
+    public SearchRequest(String from, String to, String flightDate) {
+        this.from = from;
+        this.to = to;
+        this.flightDate = flightDate;
+    }
+
+    public String getFrom() {
+        return from;
+    }
+
+    public String getTo() {
+        return to;
+    }
+
+    public String getFlightDate() {
+        return flightDate;
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/model/SearchResponse.java

@@ -0,0 +1,32 @@
+package io.reflectoring.resilience4j.retry.model;
+
+import java.util.List;
+
+public class SearchResponse {
+    String errorCode;
+    List<Flight> flights;
+
+    public String getErrorCode() {
+        return errorCode;
+    }
+
+    public void setErrorCode(String errorCode) {
+        this.errorCode = errorCode;
+    }
+
+    public List<Flight> getFlights() {
+        return flights;
+    }
+
+    public void setFlights(List<Flight> flights) {
+        this.flights = flights;
+    }
+
+    @Override
+    public String toString() {
+        return "SearchResponse{" +
+                "errorCode='" + errorCode + '\'' +
+                ", flights=" + flights +
+                '}';
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/services/FlightBookingService.java

@@ -0,0 +1,31 @@
+package io.reflectoring.resilience4j.retry.services;
+
+import io.reflectoring.resilience4j.retry.exceptions.SeatsUnavailableException;
+import io.reflectoring.resilience4j.retry.model.BookingRequest;
+import io.reflectoring.resilience4j.retry.model.BookingResponse;
+import io.reflectoring.resilience4j.retry.services.failures.NoFailure;
+import io.reflectoring.resilience4j.retry.services.failures.PotentialFailure;
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+
+public class FlightBookingService {
+    PotentialFailure potentialFailure = new NoFailure();
+    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("HH:mm:ss SSS");
+
+    public BookingResponse bookFlight(BookingRequest request) throws SeatsUnavailableException {
+        System.out.println("Booking flight; current time = " + LocalDateTime.now().format(formatter));
+        potentialFailure.occur();
+
+        if (request.getFlight().getFlightNumber().contains("765")) {
+            potentialFailure.occur();
+            throw new SeatsUnavailableException("No seats available");
+        }
+        // book seats on flight
+        System.out.println("Flight booking successful");
+        return new BookingResponse("success");
+    }
+
+    public void setPotentialFailure(PotentialFailure potentialFailure) {
+        this.potentialFailure = potentialFailure;
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/services/FlightSearchService.java

@@ -0,0 +1,68 @@
+package io.reflectoring.resilience4j.retry.services;
+
+import io.reflectoring.resilience4j.retry.model.Flight;
+import io.reflectoring.resilience4j.retry.model.SearchRequest;
+import io.reflectoring.resilience4j.retry.model.SearchResponse;
+import io.reflectoring.resilience4j.retry.services.failures.NoFailure;
+import io.reflectoring.resilience4j.retry.services.failures.PotentialFailure;
+import java.io.IOException;
+import java.time.LocalDateTime;
+import java.time.format.DateTimeFormatter;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.List;
+
+public class FlightSearchService {
+    PotentialFailure potentialFailure = new NoFailure();
+    DateTimeFormatter formatter = DateTimeFormatter.ofPattern("HH:mm:ss SSS");
+
+    public List<Flight> searchFlights(SearchRequest request) {
+        System.out.println("Searching for flights; current time = " + LocalDateTime.now().format(formatter));
+        potentialFailure.occur();
+
+        List<Flight> flights = Arrays.asList(
+                new Flight("XY 765", request.getFlightDate(), request.getFrom(), request.getTo()),
+                new Flight("XY 781", request.getFlightDate(), request.getFrom(), request.getTo()),
+                new Flight("XY 732", request.getFlightDate(), request.getFrom(), request.getTo()),
+                new Flight("XY 746", request.getFlightDate(), request.getFrom(), request.getTo())
+        );
+        System.out.println("Flight search successful");
+        return flights;
+    }
+
+    public List<Flight> searchFlightsThrowingException(SearchRequest request) throws Exception {
+        System.out.println("Searching for flights; current time = " + LocalDateTime.now().format(formatter));
+        throw new Exception("Exception when searching for flights");
+    }
+
+    public void setPotentialFailure(PotentialFailure potentialFailure) {
+        this.potentialFailure = potentialFailure;
+    }
+
+    public SearchResponse httpSearchFlights(SearchRequest request) throws IOException {
+        System.out.println("Searching for flights; current time = " + LocalDateTime.now().format(formatter));
+        potentialFailure.occur();
+
+        String date = request.getFlightDate();
+        String from = request.getFrom();
+        String to = request.getTo();
+        if (request.getFlightDate().equals("07/25/2020")) { // Simulating an error scenario
+            System.out.println("Flight data initialization in progress, cannot search at this time");
+            SearchResponse response = new SearchResponse();
+            response.setErrorCode("FS-167");
+            response.setFlights(Collections.emptyList());
+            return response;
+        }
+
+        List<Flight> flights = Arrays.asList(
+                new Flight("XY 765", date, from, to),
+                new Flight("XY 781", date, from, to),
+                new Flight("XY 732", date, from, to),
+                new Flight("XY 746", date, from, to)
+        );
+        System.out.println("Flight search successful");
+        SearchResponse response = new SearchResponse();
+        response.setFlights(flights);
+        return response;
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/services/failures/FailHalfTheTime.java

@@ -0,0 +1,25 @@
+package io.reflectoring.resilience4j.retry.services.failures;
+
+import java.util.Random;
+
+public class FailHalfTheTime implements PotentialFailure {
+    Random random = new Random();
+    int times;
+    int failedCount;
+
+    public FailHalfTheTime(int times) {
+        this.times = times;
+    }
+
+    @Override
+    public void occur() {
+        if (failedCount++ < times && random.nextInt() % 2 == 0) {
+            throw new RuntimeException("Operation failed");
+        }
+    }
+
+    public static void main(String[] args) {
+        PotentialFailure failure = new FailHalfTheTime(4);
+        failure.occur();
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/services/failures/FailNTimes.java

@@ -0,0 +1,18 @@
+package io.reflectoring.resilience4j.retry.services.failures;
+
+public class FailNTimes implements PotentialFailure {
+    int times;
+    int failedCount;
+
+    public FailNTimes(int times) {
+        this.times = times;
+    }
+
+    @Override
+    public void occur() {
+        if (failedCount++ < times) {
+            System.out.println("Operation failed");
+            throw new RuntimeException("Operation failed");
+        }
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/services/failures/NoFailure.java

@@ -0,0 +1,7 @@
+package io.reflectoring.resilience4j.retry.services.failures;
+
+public class NoFailure implements PotentialFailure {
+    @Override
+    public void occur() {
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/services/failures/PotentialFailure.java

@@ -0,0 +1,5 @@
+package io.reflectoring.resilience4j.retry.services.failures;
+
+public interface PotentialFailure {
+    void occur();
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/services/failures/RateLimitFailNTimes.java

@@ -0,0 +1,20 @@
+package io.reflectoring.resilience4j.retry.services.failures;
+
+import io.reflectoring.resilience4j.retry.exceptions.RateLimitExceededException;
+
+public class RateLimitFailNTimes implements PotentialFailure {
+    int times;
+    int failedCount;
+
+    public RateLimitFailNTimes(int times) {
+        this.times = times;
+    }
+
+    @Override
+    public void occur() {
+        if (failedCount++ < times) {
+            System.out.println("Rate limit exceeded");
+            throw new RateLimitExceededException("Rate limit exceeded, try again in some time", "RL-101");
+        }
+    }
+}

resilience4j/retry/src/main/java/io/reflectoring/resilience4j/retry/services/failures/SeatsUnavailableFailureNTimes.java

@@ -0,0 +1,20 @@
+package io.reflectoring.resilience4j.retry.services.failures;
+
+import io.reflectoring.resilience4j.retry.exceptions.SeatsUnavailableException;
+
+public class SeatsUnavailableFailureNTimes implements PotentialFailure {
+    int times;
+    int failedCount;
+
+    public SeatsUnavailableFailureNTimes(int times) {
+        this.times = times;
+    }
+
+    @Override
+    public void occur() {
+        if (failedCount++ < times) {
+            System.out.println("Seats not available");
+            throw new SeatsUnavailableException("Seats not available");
+        }
+    }
+}

solid/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ 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
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip

solid/lsp/.mvn/wrapper/MavenWrapperDownloader.java

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

solid/lsp/.mvn/wrapper/maven-wrapper.properties

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

solid/lsp/Readme.md

@@ -0,0 +1,14 @@
+There are 5 programs under com/reflectoring/examples/lsp/paymentexample.
+
+Run in this order to see class design evolution:
+1. InitialPaymentRequirementsMainApp
+2. LSPViolationMainApp
+3. ForceFitStillBrokenMainApp 
+4. ForceFitAndConditionalCodeMainApp 
+5. RedesignedMainApp
+
+Packages are organized similarly: violation, forcefit, forcefitandconditional, 
+and redesigned have specific classes modified at that point in the evolution.
+
+Common code is in common, common/exceptions, common/external and 
+common/instruments.  

solid/lsp/mvnw

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

solid/lsp/mvnw.cmd

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

solid/lsp/pom.xml

@@ -0,0 +1,74 @@
+<?xml version="1.0" encoding="UTF-8"?>
+
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>io.reflectoring.solid.lsp</groupId>
+  <artifactId>lsp</artifactId>
+  <version>1.0-SNAPSHOT</version>
+
+  <name>lsp</name>
+  <url>http://www.reflectoring.io</url>
+
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <maven.compiler.source>1.8</maven.compiler.source>
+    <maven.compiler.target>1.8</maven.compiler.target>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>4.11</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
+      <plugins>
+        <!-- clean lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#clean_Lifecycle -->
+        <plugin>
+          <artifactId>maven-clean-plugin</artifactId>
+          <version>3.1.0</version>
+        </plugin>
+        <!-- default lifecycle, jar packaging: see https://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_jar_packaging -->
+        <plugin>
+          <artifactId>maven-resources-plugin</artifactId>
+          <version>3.0.2</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-compiler-plugin</artifactId>
+          <version>3.8.0</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-surefire-plugin</artifactId>
+          <version>2.22.1</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-jar-plugin</artifactId>
+          <version>3.0.2</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-install-plugin</artifactId>
+          <version>2.5.2</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-deploy-plugin</artifactId>
+          <version>2.8.2</version>
+        </plugin>
+        <!-- site lifecycle, see https://maven.apache.org/ref/current/maven-core/lifecycles.html#site_Lifecycle -->
+        <plugin>
+          <artifactId>maven-site-plugin</artifactId>
+          <version>3.7.1</version>
+        </plugin>
+        <plugin>
+          <artifactId>maven-project-info-reports-plugin</artifactId>
+          <version>3.0.0</version>
+        </plugin>
+      </plugins>
+    </pluginManagement>
+  </build>
+</project>

solid/lsp/src/main/java/io/reflectoring/solid/lsp/genericexample/SomeClass.java

@@ -0,0 +1,11 @@
+package io.reflectoring.solid.lsp.genericexample;
+
+public class SomeClass {
+    void aMethod(SuperClass superClassReference) {
+        doSomething(superClassReference);
+    }
+
+    void doSomething(SuperClass superClassReference) {
+
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/genericexample/SuperClass.java

@@ -0,0 +1,4 @@
+package io.reflectoring.solid.lsp.genericexample;
+
+public class SuperClass {
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/ForceFitAndConditionalCodeMainApp.java

@@ -0,0 +1,111 @@
+package io.reflectoring.solid.lsp.paymentexample;
+
+import io.reflectoring.solid.lsp.paymentexample.common.OrderDetails;
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.CreditCard;
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.DebitCard;
+import io.reflectoring.solid.lsp.paymentexample.forcefitandconditional.PaymentProcessor;
+import io.reflectoring.solid.lsp.paymentexample.forcefitandconditional.instruments.RewardsCard;
+import java.util.Date;
+import java.util.Scanner;
+
+public class ForceFitAndConditionalCodeMainApp {
+    public static void main(String[] args) {
+        System.out.println("This program simulates the different flows through the payment system.");
+        System.out.println("This version shows how force-fitting the new class RewardsCard "
+            + "into the current class hierarchy and adding conditional checks fixes LSP violation but results in "
+            + " code that is difficult to maintain.");
+        System.out.println();
+        System.out.println("Available flows: ");
+
+        System.out.println("1. Successful credit card payment flow");
+        System.out.println("2. Unsuccessful credit card payment - fraud detected flow");
+        System.out.println("3. Unsuccessful credit card payment - payment gateway error");
+
+        System.out.println("4. Successful debit card payment flow");
+        System.out.println("5. Unsuccessful debit card payment - fraud detected flow");
+        System.out.println("6. Unsuccessful debit card payment - payment gateway error");
+
+        System.out.println("7. Successful rewards card payment flow");
+        System.out.print("Select the flow you want to simulate, no other inputs required: ");
+
+        PaymentProcessor processor = new PaymentProcessor();
+        Scanner input = new Scanner(System.in);
+        int flow = input.nextInt();
+        System.out.println("----------------------------------------------------------------------");
+        String name = "John Smith";
+        String code = "123";
+        String orderNum = "default-order-123";
+        OrderDetails order = new OrderDetails();
+        order.setOrderNumber(orderNum);
+
+        switch (flow) {
+            case 1:
+                String cardNum = "4567876523455432";
+                CreditCard card = new CreditCard(name, cardNum, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum);
+                processor.process(order, card);
+                System.out.println("Credit card payment completed successfully!");
+
+                break;
+            case 2:
+                String cardNum2 = "0567876523455432";
+                CreditCard card2 = new CreditCard(name, cardNum2, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum2);
+                processor.process(order, card2);
+                System.out.println("Credit card payment failed!");
+
+                break;
+            case 3:
+                String cardNum3 = "1567876523455432";
+                CreditCard card3 = new CreditCard(name, cardNum3, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum3);
+                processor.process(order, card3);
+                System.out.println("Credit card payment failed!");
+
+                break;
+            case 4:
+                String cardNum4 = "6567876523455432";
+                DebitCard card4 = new DebitCard(name, cardNum4, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum4);
+                processor.process(order, card4);
+                System.out.println("Debit card payment completed successfully!");
+
+                break;
+            case 5:
+                String cardNum5 = "0567876523455432";
+                DebitCard card5 = new DebitCard(name, cardNum5, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum5);
+                processor.process(order, card5);
+                System.out.println("Debit card payment failed!");
+
+                break;
+            case 6:
+                String cardNum6 = "1567876523455432";
+                DebitCard card6 = new DebitCard(name, cardNum6, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum6);
+                processor.process(order, card6);
+                System.out.println("Debit card payment failed!");
+
+                break;
+            case 7:
+                String cardNum7 = "25678765";
+                RewardsCard card7 = new RewardsCard(name, cardNum7, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with rewards card number " + cardNum7);
+                processor.process(order, card7);
+                System.out.println("Rewards card payment successful!");
+
+                break;
+
+            default:
+                System.out.println("Invalid flow selected");
+                break;
+        }
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/ForceFitStillBrokenMainApp.java

@@ -0,0 +1,109 @@
+package io.reflectoring.solid.lsp.paymentexample;
+
+import io.reflectoring.solid.lsp.paymentexample.common.OrderDetails;
+import io.reflectoring.solid.lsp.paymentexample.common.PaymentProcessor;
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.CreditCard;
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.DebitCard;
+import io.reflectoring.solid.lsp.paymentexample.forcefit.instruments.RewardsCard;
+import java.util.Date;
+import java.util.Scanner;
+
+public class ForceFitStillBrokenMainApp {
+    public static void main(String[] args) {
+        System.out.println("This program simulates the different flows through the payment system.");
+        System.out.println("This version shows how force-fitting the new class RewardsCard "
+            + "into the current class hierarchy still violates LSP.");
+        System.out.println();
+        System.out.println("Available flows: ");
+        System.out.println("1. Successful credit card payment flow");
+        System.out.println("2. Unsuccessful credit card payment - fraud detected flow");
+        System.out.println("3. Unsuccessful credit card payment - payment gateway error");
+
+        System.out.println("4. Successful debit card payment flow");
+        System.out.println("5. Unsuccessful debit card payment - fraud detected flow");
+        System.out.println("6. Unsuccessful debit card payment - payment gateway error");
+
+        System.out.println("7. Rewards card attempt - broken app flow");
+        System.out.print("Select the flow you want to simulate, no other inputs required: ");
+
+        PaymentProcessor processor = new PaymentProcessor();
+        Scanner input = new Scanner(System.in);
+        int flow = input.nextInt();
+        System.out.println("----------------------------------------------------------------------");
+        String name = "John Smith";
+        String code = "123";
+        String orderNum = "default-order-123";
+        OrderDetails order = new OrderDetails();
+        order.setOrderNumber(orderNum);
+
+        switch (flow) {
+            case 1:
+                String cardNum = "4567876523455432";
+                CreditCard card = new CreditCard(name, cardNum, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum);
+                processor.process(order, card);
+                System.out.println("Credit card payment completed successfully!");
+
+                break;
+            case 2:
+                String cardNum2 = "0567876523455432";
+                CreditCard card2 = new CreditCard(name, cardNum2, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum2);
+                processor.process(order, card2);
+                System.out.println("Credit card payment failed!");
+
+                break;
+            case 3:
+                String cardNum3 = "1567876523455432";
+                CreditCard card3 = new CreditCard(name, cardNum3, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum3);
+                processor.process(order, card3);
+                System.out.println("Credit card payment failed!");
+
+                break;
+            case 4:
+                String cardNum4 = "6567876523455432";
+                DebitCard card4 = new DebitCard(name, cardNum4, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum4);
+                processor.process(order, card4);
+                System.out.println("Debit card payment completed successfully!");
+
+                break;
+            case 5:
+                String cardNum5 = "0567876523455432";
+                DebitCard card5 = new DebitCard(name, cardNum5, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum5);
+                processor.process(order, card5);
+                System.out.println("Debit card payment failed!");
+
+                break;
+            case 6:
+                String cardNum6 = "1567876523455432";
+                DebitCard card6 = new DebitCard(name, cardNum6, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum6);
+                processor.process(order, card6);
+                System.out.println("Debit card payment failed!");
+
+                break;
+            case 7:
+                String cardNum7 = "25678765";
+                RewardsCard card7 = new RewardsCard(name, cardNum7, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with rewards card number " + cardNum7);
+                processor.process(order, card7);
+                System.out.println("Rewards card payment failed!");
+
+                break;
+
+            default:
+                System.out.println("Invalid flow selected");
+                break;
+        }
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/InitialPaymentRequirementsMainApp.java

@@ -0,0 +1,96 @@
+package io.reflectoring.solid.lsp.paymentexample;
+
+import io.reflectoring.solid.lsp.paymentexample.common.PaymentProcessor;
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.CreditCard;
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.DebitCard;
+import io.reflectoring.solid.lsp.paymentexample.common.OrderDetails;
+import java.util.Date;
+import java.util.Scanner;
+
+public class InitialPaymentRequirementsMainApp {
+    public static void main(String[] args) {
+        System.out.println("This program simulates the different flows through the payment system.");
+        System.out.println("This version is based on the initial requirements for credit and debit cards.");
+        System.out.println();
+        System.out.println("Available flows: ");
+        System.out.println("1. Successful credit card payment flow");
+        System.out.println("2. Unsuccessful credit card payment - fraud detected flow");
+        System.out.println("3. Unsuccessful credit card payment - payment gateway error");
+
+        System.out.println("4. Successful debit card payment flow");
+        System.out.println("5. Unsuccessful debit card payment - fraud detected flow");
+        System.out.println("6. Unsuccessful debit card payment - payment gateway error");
+
+        System.out.print("Select the flow you want to simulate, no other inputs required: ");
+
+        PaymentProcessor processor = new PaymentProcessor();
+        Scanner input = new Scanner(System.in);
+        int flow = input.nextInt();
+        System.out.println("----------------------------------------------------------------------");
+        String name = "John Smith";
+        String code = "123";
+        String orderNum = "default-order-123";
+        OrderDetails order = new OrderDetails();
+        order.setOrderNumber(orderNum);
+
+        switch (flow) {
+            case 1:
+                String cardNum = "4567876523455432";
+                CreditCard card = new CreditCard(name, cardNum, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum);
+                processor.process(order, card);
+                System.out.println("Credit card payment completed successfully!");
+
+                break;
+            case 2:
+                String cardNum2 = "0567876523455432";
+                CreditCard card2 = new CreditCard(name, cardNum2, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum2);
+                processor.process(order, card2);
+                System.out.println("Credit card payment failed!");
+
+                break;
+            case 3:
+                String cardNum3 = "1567876523455432";
+                CreditCard card3 = new CreditCard(name, cardNum3, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum3);
+                processor.process(order, card3);
+                System.out.println("Credit card payment failed!");
+
+                break;
+            case 4:
+                String cardNum4 = "6567876523455432";
+                DebitCard card4 = new DebitCard(name, cardNum4, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum4);
+                processor.process(order, card4);
+                System.out.println("Debit card payment completed successfully!");
+
+                break;
+            case 5:
+                String cardNum5 = "0567876523455432";
+                DebitCard card5 = new DebitCard(name, cardNum5, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum5);
+                processor.process(order, card5);
+                System.out.println("Debit card payment failed!");
+
+                break;
+            case 6:
+                String cardNum6 = "1567876523455432";
+                DebitCard card6 = new DebitCard(name, cardNum6, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum6);
+                processor.process(order, card6);
+                System.out.println("Debit card payment failed!");
+
+                break;
+            default:
+                System.out.println("Invalid flow selected");
+                break;
+        }
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/LSPViolationMainApp.java

@@ -0,0 +1,109 @@
+package io.reflectoring.solid.lsp.paymentexample;
+
+import io.reflectoring.solid.lsp.paymentexample.common.OrderDetails;
+import io.reflectoring.solid.lsp.paymentexample.common.PaymentProcessor;
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.CreditCard;
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.DebitCard;
+import io.reflectoring.solid.lsp.paymentexample.violation.instruments.RewardsCard;
+import java.util.Date;
+import java.util.Scanner;
+
+public class LSPViolationMainApp {
+    public static void main(String[] args) {
+        System.out.println("This program simulates the different flows through the payment system.");
+        System.out.println("This version adds a new class RewardsCard to the class hierarchy and demonstrates"
+            + " LSP violation.");
+        System.out.println();
+        System.out.println("Available flows: ");
+        System.out.println("1. Successful credit card payment flow");
+        System.out.println("2. Unsuccessful credit card payment - fraud detected flow");
+        System.out.println("3. Unsuccessful credit card payment - payment gateway error");
+
+        System.out.println("4. Successful debit card payment flow");
+        System.out.println("5. Unsuccessful debit card payment - fraud detected flow");
+        System.out.println("6. Unsuccessful debit card payment - payment gateway error");
+
+        System.out.println("7. Rewards card attempt - broken app flow");
+        System.out.print("Select the flow you want to simulate, no other inputs required: ");
+
+        PaymentProcessor processor = new PaymentProcessor();
+        Scanner input = new Scanner(System.in);
+        int flow = input.nextInt();
+        System.out.println("----------------------------------------------------------------------");
+        String name = "John Smith";
+        String code = "123";
+        String orderNum = "default-order-123";
+        OrderDetails order = new OrderDetails();
+        order.setOrderNumber(orderNum);
+
+        switch (flow) {
+            case 1:
+                String cardNum = "4567876523455432";
+                CreditCard card = new CreditCard(name, cardNum, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum);
+                processor.process(order, card);
+                System.out.println("Credit card payment completed successfully!");
+
+                break;
+            case 2:
+                String cardNum2 = "0567876523455432";
+                CreditCard card2 = new CreditCard(name, cardNum2, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum2);
+                processor.process(order, card2);
+                System.out.println("Credit card payment failed!");
+
+                break;
+            case 3:
+                String cardNum3 = "1567876523455432";
+                CreditCard card3 = new CreditCard(name, cardNum3, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum3);
+                processor.process(order, card3);
+                System.out.println("Credit card payment failed!");
+
+                break;
+            case 4:
+                String cardNum4 = "6567876523455432";
+                DebitCard card4 = new DebitCard(name, cardNum4, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum4);
+                processor.process(order, card4);
+                System.out.println("Debit card payment completed successfully!");
+
+                break;
+            case 5:
+                String cardNum5 = "0567876523455432";
+                DebitCard card5 = new DebitCard(name, cardNum5, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum5);
+                processor.process(order, card5);
+                System.out.println("Debit card payment failed!");
+
+                break;
+            case 6:
+                String cardNum6 = "1567876523455432";
+                DebitCard card6 = new DebitCard(name, cardNum6, code, new Date());
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum6);
+                processor.process(order, card6);
+                System.out.println("Debit card payment failed!");
+
+                break;
+            case 7:
+                String cardNum7 = "25678765";
+                RewardsCard card7 = new RewardsCard(name, cardNum7, null, null);
+
+                System.out.println("Starting payment processing for customer " + name + " with rewards card number " + cardNum7);
+                processor.process(order, card7);
+                System.out.println("Rewards card payment failed!");
+
+                break;
+
+            default:
+                System.out.println("Invalid flow selected");
+                break;
+        }
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/RedesignedMainApp.java

@@ -0,0 +1,142 @@
+package io.reflectoring.solid.lsp.paymentexample;
+
+import io.reflectoring.solid.lsp.paymentexample.common.OrderDetails;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.PaymentProcessor;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.fraud.IFraudChecker;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.fraud.ThirdPartyFraudChecker;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.instruments.CreditCard;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.instruments.DebitCard;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.instruments.RewardsCard;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.paymentgateway.IPaymentGatewayHandler;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.paymentgateway.PaymentGatewayHandler;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.validators.BankCardBasicValidator;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.validators.IPaymentInstrumentValidator;
+import java.util.Date;
+import java.util.Scanner;
+
+public class RedesignedMainApp {
+    public static void main(String[] args) {
+        System.out.println("This program simulates the different flows through the payment system.");
+        System.out.println("This version shows how fixing the class hierarchy issues fixes LSP violation and "
+            + "also makes the solution more flexible.");
+        System.out.println();
+        System.out.println("Available flows: ");
+
+        System.out.println("1. Successful credit card payment flow");
+        System.out.println("2. Unsuccessful credit card payment - fraud detected flow");
+        System.out.println("3. Unsuccessful credit card payment - payment gateway error");
+
+        System.out.println("4. Successful debit card payment flow");
+        System.out.println("5. Unsuccessful debit card payment - fraud detected flow");
+        System.out.println("6. Unsuccessful debit card payment - payment gateway error");
+
+        System.out.println("7. Successful rewards card payment flow");
+        System.out.print("Just select the flow you want to simulate, no other inputs required: ");
+
+        PaymentProcessor paymentProcessor = new PaymentProcessor();
+        Scanner input = new Scanner(System.in);
+        int flow = input.nextInt();
+        System.out.println("----------------------------------------------------------------------");
+        String name = "John Smith";
+        String code = "123";
+        String orderNum = "default-order-123";
+        OrderDetails order = new OrderDetails();
+        order.setOrderNumber(orderNum);
+
+        switch (flow) {
+            case 1:
+                String cardNum = "4567876523455432";
+                Date expiryDate = new Date();
+                IPaymentInstrumentValidator validator = new BankCardBasicValidator(name, cardNum, code, expiryDate);
+                IFraudChecker fraudChecker = new ThirdPartyFraudChecker(name, cardNum, code, expiryDate);
+                IPaymentGatewayHandler gatewayHandler = new PaymentGatewayHandler(name, cardNum, code, expiryDate);
+                CreditCard card = new CreditCard(name, cardNum, code, new Date(), validator, fraudChecker, gatewayHandler);
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum);
+                paymentProcessor.process(order, card);
+                System.out.println("Credit card payment completed successfully!");
+
+                break;
+            case 2:
+                String cardNum2 = "0567876523455432";
+                Date expiryDate2 = new Date();
+                IPaymentGatewayHandler gatewayHandler2 = new PaymentGatewayHandler(name, cardNum2, code, expiryDate2);
+                IFraudChecker fraudChecker2 = new ThirdPartyFraudChecker(name, cardNum2, code, expiryDate2);
+                IPaymentInstrumentValidator validator2 = new BankCardBasicValidator(name, cardNum2, code, expiryDate2);
+                CreditCard card2 = new CreditCard(name, cardNum2, code, new Date(), validator2, fraudChecker2, gatewayHandler2);
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum2);
+                paymentProcessor.process(order, card2);
+                System.out.println("Credit card payment failed!");
+
+                break;
+            case 3:
+                String cardNum3 = "1567876523455432";
+                Date expiryDate3 = new Date();
+                IPaymentGatewayHandler gatewayHandler3 = new PaymentGatewayHandler(name, cardNum3, code, expiryDate3);
+                IPaymentInstrumentValidator validator3 = new BankCardBasicValidator(name, cardNum3, code, expiryDate3);
+                IFraudChecker fraudChecker3 = new ThirdPartyFraudChecker(name, cardNum3, code, expiryDate3);
+                CreditCard card3 = new CreditCard(name, cardNum3, code, new Date(), validator3, fraudChecker3, gatewayHandler3);
+
+                System.out.println("Starting payment processing for customer " + name + " with credit card number " + cardNum3);
+                paymentProcessor.process(order, card3);
+                System.out.println("Credit card payment failed!");
+
+                break;
+            case 4:
+                String cardNum4 = "6567876523455432";
+                Date expiryDate4 = new Date();
+                IPaymentGatewayHandler gatewayHandler4 = new PaymentGatewayHandler(name, cardNum4, code, expiryDate4);
+                IPaymentInstrumentValidator validator4 = new BankCardBasicValidator(name, cardNum4, code, expiryDate4);
+                IFraudChecker fraudChecker4 = new ThirdPartyFraudChecker(name, cardNum4, code, expiryDate4);
+                DebitCard card4 = new DebitCard(name, cardNum4, code, new Date(), validator4, fraudChecker4, gatewayHandler4);
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum4);
+                paymentProcessor.process(order, card4);
+                System.out.println("Debit card payment completed successfully!");
+
+                break;
+            case 5:
+                String cardNum5 = "0567876523455432";
+                Date expiryDate5 = new Date();
+                IPaymentGatewayHandler gatewayHandler5 = new PaymentGatewayHandler(name, cardNum5, code, expiryDate5);
+                IPaymentInstrumentValidator validator5 = new BankCardBasicValidator(name, cardNum5, code, expiryDate5);
+                IFraudChecker fraudChecker5 = new ThirdPartyFraudChecker(name, cardNum5, code, expiryDate5);
+
+                DebitCard card5 = new DebitCard(name, cardNum5, code, new Date(), validator5, fraudChecker5, gatewayHandler5);
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum5);
+                paymentProcessor.process(order, card5);
+                System.out.println("Debit card payment failed!");
+
+                break;
+            case 6:
+                String cardNum6 = "1567876523455432";
+                Date expiryDate6 = new Date();
+                IPaymentGatewayHandler gatewayHandler6 = new PaymentGatewayHandler(name, cardNum6, code, expiryDate6);
+                IPaymentInstrumentValidator validator6 = new BankCardBasicValidator(name, cardNum6, code, expiryDate6);
+                IFraudChecker fraudChecker6 = new ThirdPartyFraudChecker(name, cardNum6, code, expiryDate6);
+
+                DebitCard card6 = new DebitCard(name, cardNum6, code, new Date(), validator6, fraudChecker6, gatewayHandler6);
+
+                System.out.println("Starting payment processing for customer " + name + " with debit card number " + cardNum6);
+                paymentProcessor.process(order, card6);
+                System.out.println("Debit card payment failed!");
+
+                break;
+            case 7:
+                String cardNum7 = "25678765";
+                RewardsCard card7 = new RewardsCard(name, cardNum7);
+
+                System.out.println("Starting payment processing for customer " + name + " with rewards card number " + cardNum7);
+                paymentProcessor.process(order, card7);
+                System.out.println("Rewards card payment successful!");
+
+                break;
+
+            default:
+                System.out.println("Invalid flow selected");
+                break;
+        }
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/common/OrderDetails.java

@@ -0,0 +1,9 @@
+package io.reflectoring.solid.lsp.paymentexample.common;
+
+public class OrderDetails {
+  String orderNumber;
+
+  public void setOrderNumber(String orderNumber) {
+    this.orderNumber = orderNumber;
+  }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/common/PaymentProcessor.java

@@ -0,0 +1,31 @@
+package io.reflectoring.solid.lsp.paymentexample.common;
+
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.PaymentInstrument;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.FraudDetectedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+
+public class PaymentProcessor {
+  public void process(OrderDetails orderDetails, PaymentInstrument paymentInstrument) {
+    try {
+      paymentInstrument.validate();
+      paymentInstrument.runFraudChecks();
+      paymentInstrument.sendToPaymentGateway();
+      saveToDatabase(orderDetails, paymentInstrument);
+    } catch (PaymentInstrumentInvalidException e) {
+      e.printStackTrace();
+    } catch (FraudDetectedException e) {
+      e.printStackTrace();
+    } catch (PaymentFailedException e) {
+      e.printStackTrace();
+    }
+  }
+
+  void saveToDatabase(OrderDetails orderDetails, PaymentInstrument paymentInstrument) {
+    String identifier = paymentInstrument.getFingerprint();
+    // save fingerprint and order details in DB
+    if (identifier == null) {
+      throw new NullPointerException("Fingerprint/identifier is required to save to database");
+    }
+  }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/common/exceptions/FraudDetectedException.java

@@ -0,0 +1,7 @@
+package io.reflectoring.solid.lsp.paymentexample.common.exceptions;
+
+public class FraudDetectedException extends Exception {
+    public FraudDetectedException(String message) {
+        super(message);
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/common/exceptions/PaymentFailedException.java

@@ -0,0 +1,7 @@
+package io.reflectoring.solid.lsp.paymentexample.common.exceptions;
+
+public class PaymentFailedException extends Exception {
+    public PaymentFailedException(String message) {
+        super(message);
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/common/exceptions/PaymentInstrumentInvalidException.java

@@ -0,0 +1,7 @@
+package io.reflectoring.solid.lsp.paymentexample.common.exceptions;
+
+public class PaymentInstrumentInvalidException extends Exception {
+    public PaymentInstrumentInvalidException(String message) {
+        super(message);
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/common/external/PaymentGateway.java

@@ -0,0 +1,25 @@
+package io.reflectoring.solid.lsp.paymentexample.common.external;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import java.util.Date;
+import java.util.UUID;
+
+public class PaymentGateway {
+    public String process(String name, String cardNumber, String verificationCode, Date expiryDate) throws PaymentFailedException {
+        // sleep 2s to simulate network latency
+        try {
+            Thread.sleep(2000);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+
+        if (cardNumber.startsWith("1")) {
+            throw new PaymentFailedException("Payment failed!");
+        }
+
+        if (cardNumber.startsWith("2")) {
+            throw new PaymentFailedException("Unrecognized card type, payment failed!");
+        }
+        return UUID.randomUUID().toString();
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/common/external/ThirdPartyFraudDetectionSystem.java

@@ -0,0 +1,23 @@
+package io.reflectoring.solid.lsp.paymentexample.common.external;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.FraudDetectedException;
+import java.util.Date;
+
+public class ThirdPartyFraudDetectionSystem {
+    public void process(String name, String cardNumber, String verificationCode, Date expiryDate) throws FraudDetectedException {
+        // sleep 2s to simulate network latency
+        try {
+            Thread.sleep(2000);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+
+        if (cardNumber.startsWith("0")) {
+            throw new FraudDetectedException("Fraud detected!");
+        }
+
+        if (cardNumber.startsWith("2")) {
+            throw new FraudDetectedException("Unrecognized card type for fraud detection!");
+        }
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/common/instruments/CreditCard.java

@@ -0,0 +1,18 @@
+package io.reflectoring.solid.lsp.paymentexample.common.instruments;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+import java.util.Date;
+
+public class CreditCard extends PaymentInstrument {
+
+  public CreditCard(String name, String cardNumber, String verificationCode,
+      Date expiryDate) {
+    super(name, cardNumber, verificationCode, expiryDate);
+  }
+
+  @Override
+  public void validate() throws PaymentInstrumentInvalidException {
+    super.validate();
+    // additional validations for credit cards
+  }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/common/instruments/DebitCard.java

@@ -0,0 +1,11 @@
+package io.reflectoring.solid.lsp.paymentexample.common.instruments;
+
+import java.util.Date;
+
+public class DebitCard extends PaymentInstrument {
+
+  public DebitCard(String name, String cardNumber, String verificationCode,
+      Date expiryDate) {
+    super(name, cardNumber, verificationCode, expiryDate);
+  }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/common/instruments/PaymentInstrument.java

@@ -0,0 +1,53 @@
+package io.reflectoring.solid.lsp.paymentexample.common.instruments;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.FraudDetectedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+import io.reflectoring.solid.lsp.paymentexample.common.external.PaymentGateway;
+import io.reflectoring.solid.lsp.paymentexample.common.external.ThirdPartyFraudDetectionSystem;
+import java.util.Date;
+
+public abstract class PaymentInstrument {
+  String name;
+  String cardNumber;
+  String verificationCode;
+  Date expiryDate;
+  String fingerprint;
+  ThirdPartyFraudDetectionSystem fraudDetection = new ThirdPartyFraudDetectionSystem();
+  PaymentGateway paymentGateway = new PaymentGateway();
+
+  public PaymentInstrument(String name, String cardNumber, String verificationCode,
+      Date expiryDate) {
+    this.name = name;
+    this.cardNumber = cardNumber;
+    this.verificationCode = verificationCode;
+    this.expiryDate = expiryDate;
+  }
+
+  public void validate() throws PaymentInstrumentInvalidException {
+    // basic validation on name, expiryDate etc.
+    if (name == null || name.isEmpty()) {
+      throw new PaymentInstrumentInvalidException("Name is invalid");
+    }
+    // other validations
+  }
+
+  public void runFraudChecks() throws FraudDetectedException {
+    // run checks against a third-party system
+    System.out.println("Running fraud checks against third-party system");
+    fraudDetection.process(name, cardNumber, verificationCode, expiryDate);
+    System.out.println("Fraud checks passed");
+  }
+
+  public void sendToPaymentGateway() throws PaymentFailedException {
+    // send details to payment gateway (PG) and save the fingerprint
+    // received from PG
+    System.out.println("Sending details to payment gateway");
+    this.fingerprint = paymentGateway.process(name, cardNumber, verificationCode, expiryDate);
+    System.out.println("Payment gateway response received");
+  }
+
+  public String getFingerprint() {
+    return fingerprint;
+  }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/forcefit/instruments/RewardsCard.java

@@ -0,0 +1,25 @@
+package io.reflectoring.solid.lsp.paymentexample.forcefit.instruments;
+
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.PaymentInstrument;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.FraudDetectedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import java.util.Date;
+
+public class RewardsCard extends PaymentInstrument {
+    public RewardsCard(String name, String cardNumber, String verificationCode, Date expiryDate) {
+        // Reward cards don't have verification code and expiry date, so we pass null
+        super(name, cardNumber, null, null);
+    }
+
+    @Override
+    public void runFraudChecks() throws FraudDetectedException {
+        // do nothing since Rewards Cards don't require fraud detection
+        System.out.println("Doing nothing related to fraud checks in overridden method");
+    }
+
+    @Override
+    public void sendToPaymentGateway() throws PaymentFailedException {
+        // do nothing since Rewards Cards don't communicate with payment gateways
+        System.out.println("Doing nothing related to payment gateway in overridden method");
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/forcefitandconditional/PaymentProcessor.java

@@ -0,0 +1,40 @@
+package io.reflectoring.solid.lsp.paymentexample.forcefitandconditional;
+
+import io.reflectoring.solid.lsp.paymentexample.common.OrderDetails;
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.PaymentInstrument;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.FraudDetectedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+import io.reflectoring.solid.lsp.paymentexample.forcefitandconditional.instruments.RewardsCard;
+
+public class PaymentProcessor {
+  public void process(OrderDetails orderDetails, PaymentInstrument paymentInstrument) {
+    try {
+      paymentInstrument.validate();
+      paymentInstrument.runFraudChecks();
+      paymentInstrument.sendToPaymentGateway();
+      saveToDatabase(orderDetails, paymentInstrument);
+    } catch (PaymentInstrumentInvalidException e) {
+      e.printStackTrace();
+    } catch (FraudDetectedException e) {
+      e.printStackTrace();
+    } catch (PaymentFailedException e) {
+      e.printStackTrace();
+    }
+  }
+
+  void saveToDatabase(OrderDetails orderDetails, PaymentInstrument paymentInstrument) {
+    String fingerprint = paymentInstrument.getFingerprint();
+
+    if (paymentInstrument instanceof RewardsCard) {
+      System.out.println("Rewards cards don't have a fingerprint, using card number itself instead");
+      // update rewards points and save in DB
+    }
+    else {
+      // save fingerprint and order details in DB
+      if (fingerprint == null) {
+        throw new NullPointerException("Fingerprint is required to save to database");
+      }
+    }
+  }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/forcefitandconditional/instruments/RewardsCard.java

@@ -0,0 +1,25 @@
+package io.reflectoring.solid.lsp.paymentexample.forcefitandconditional.instruments;
+
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.PaymentInstrument;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.FraudDetectedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import java.util.Date;
+
+public class RewardsCard extends PaymentInstrument {
+    public RewardsCard(String name, String cardNumber, String verificationCode, Date expiryDate) {
+        // Reward cards don't have verification code and expiry date, so we are forced to pass null
+        super(name, cardNumber, null, null);
+    }
+
+    @Override
+    public void runFraudChecks() throws FraudDetectedException {
+        // do nothing since Rewards Cards don't require fraud detection
+        System.out.println("Doing nothing related to fraud checks in overridden method");
+    }
+
+    @Override
+    public void sendToPaymentGateway() throws PaymentFailedException {
+        // do nothing since Rewards Cards don't communicate with payment gateways
+        System.out.println("Doing nothing related to payment gateway in overridden method");
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/PaymentProcessor.java

@@ -0,0 +1,25 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned;
+
+import io.reflectoring.solid.lsp.paymentexample.common.OrderDetails;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.instruments.IPaymentInstrument;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.model.PaymentResponse;
+
+public class PaymentProcessor {
+    public void process(OrderDetails orderDetails, IPaymentInstrument paymentInstrument) {
+        try {
+            paymentInstrument.validate();
+            PaymentResponse response = paymentInstrument.collectPayment();
+            saveToDatabase(orderDetails, response.getIdentifier());
+        } catch (PaymentInstrumentInvalidException e) {
+            e.printStackTrace();
+        } catch (PaymentFailedException e) {
+            e.printStackTrace();
+        }
+    }
+
+    void saveToDatabase(OrderDetails orderDetails, String identifier) {
+        // save the identifier and order details in DB
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/fraud/IFraudChecker.java

@@ -0,0 +1,7 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.fraud;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.FraudDetectedException;
+
+public interface IFraudChecker {
+    void runChecks() throws FraudDetectedException;
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/fraud/ThirdPartyFraudChecker.java

@@ -0,0 +1,30 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.fraud;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.FraudDetectedException;
+import io.reflectoring.solid.lsp.paymentexample.common.external.ThirdPartyFraudDetectionSystem;
+import java.util.Date;
+
+public class ThirdPartyFraudChecker implements IFraudChecker {
+    String name;
+    String cardNumber;
+    String verificationCode;
+    Date expiryDate;
+
+    ThirdPartyFraudDetectionSystem fraudDetection = new ThirdPartyFraudDetectionSystem();
+
+    public ThirdPartyFraudChecker(String name, String cardNumber, String verificationCode, Date expiryDate) {
+        this.name = name;
+        this.cardNumber = cardNumber;
+        this.verificationCode = verificationCode;
+        this.expiryDate = expiryDate;
+    }
+
+    @Override
+    public void runChecks() throws FraudDetectedException {
+        // run checks against a third-party system
+        System.out.println("Running fraud checks against third-party system");
+        fraudDetection.process(name, cardNumber, verificationCode, expiryDate);
+        System.out.println("Fraud checks passed");
+
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/instruments/BaseBankCard.java

@@ -0,0 +1,56 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.instruments;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.FraudDetectedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.fraud.IFraudChecker;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.model.PaymentGatewayResponse;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.model.PaymentResponse;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.paymentgateway.IPaymentGatewayHandler;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.validators.IPaymentInstrumentValidator;
+import java.util.Date;
+
+public abstract class BaseBankCard implements IPaymentInstrument {
+    String name;
+    String cardNumber;
+    String verificationCode;
+    Date expiryDate;
+    String fingerprint;
+    IPaymentInstrumentValidator basicValidator;
+    IFraudChecker fraudChecker;
+    IPaymentGatewayHandler gatewayHandler;
+
+    public BaseBankCard(String name,
+                      String cardNumber,
+                      String verificationCode,
+                      Date expiryDate,
+                      IPaymentInstrumentValidator basicValidator,
+                      IFraudChecker fraudChecker,
+                      IPaymentGatewayHandler gatewayHandler) {
+        this.name = name;
+        this.cardNumber = cardNumber;
+        this.verificationCode = verificationCode;
+        this.expiryDate = expiryDate;
+        this.basicValidator = basicValidator;
+        this.fraudChecker = fraudChecker;
+        this.gatewayHandler = gatewayHandler;
+    }
+
+    @Override
+    public void validate() throws PaymentInstrumentInvalidException {
+        basicValidator.validate();
+    }
+
+    @Override
+    public PaymentResponse collectPayment() throws PaymentFailedException {
+        PaymentResponse response = new PaymentResponse();
+        try {
+            fraudChecker.runChecks();
+            PaymentGatewayResponse pgResponse = gatewayHandler.handlePayment();
+            response.setIdentifier(pgResponse.getFingerprint());
+        } catch (FraudDetectedException e) {
+            e.printStackTrace();
+        }
+        return response;
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/instruments/CreditCard.java

@@ -0,0 +1,27 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.instruments;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.fraud.IFraudChecker;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.paymentgateway.IPaymentGatewayHandler;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.validators.IPaymentInstrumentValidator;
+import java.util.Date;
+
+public class CreditCard extends BaseBankCard {
+
+  public CreditCard(String name,
+                    String cardNumber,
+                    String verificationCode,
+                    Date expiryDate,
+                    IPaymentInstrumentValidator basicValidator,
+                    IFraudChecker fraudChecker,
+                    IPaymentGatewayHandler gatewayHandler) {
+    super(name, cardNumber, verificationCode, expiryDate, basicValidator, fraudChecker, gatewayHandler);
+  }
+
+  @Override
+  public void validate() throws PaymentInstrumentInvalidException {
+    basicValidator.validate();
+    // additional validations for credit cards
+  }
+
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/instruments/DebitCard.java

@@ -0,0 +1,19 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.instruments;
+
+import io.reflectoring.solid.lsp.paymentexample.redesigned.fraud.IFraudChecker;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.paymentgateway.IPaymentGatewayHandler;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.validators.IPaymentInstrumentValidator;
+import java.util.Date;
+
+public class DebitCard extends BaseBankCard {
+
+  public DebitCard(String name,
+                   String cardNumber,
+                   String verificationCode,
+                   Date expiryDate,
+                   IPaymentInstrumentValidator basicValidator,
+                   IFraudChecker fraudChecker,
+                   IPaymentGatewayHandler gatewayHandler) {
+    super(name, cardNumber, verificationCode, expiryDate, basicValidator, fraudChecker, gatewayHandler);
+  }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/instruments/IPaymentInstrument.java

@@ -0,0 +1,10 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.instruments;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.model.PaymentResponse;
+
+public interface IPaymentInstrument  {
+    void validate() throws PaymentInstrumentInvalidException;
+    PaymentResponse collectPayment() throws PaymentFailedException;
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/instruments/RewardsCard.java

@@ -0,0 +1,37 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.instruments;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.model.PaymentResponse;
+
+public class RewardsCard implements IPaymentInstrument {
+    String name;
+    String cardNumber;
+
+    public RewardsCard(String name, String cardNumber) {
+        this.name = name;
+        this.cardNumber = cardNumber;
+    }
+
+    @Override
+    public void validate() throws PaymentInstrumentInvalidException {
+        if (name == null || name.isEmpty()) {
+            throw new PaymentInstrumentInvalidException("Name is invalid");
+        }
+
+        if (cardNumber == null || cardNumber.isEmpty()) {
+            throw new PaymentInstrumentInvalidException("Card number is invalid");
+        }
+        // Any other rewards card specific validations
+    }
+
+    @Override
+    public PaymentResponse collectPayment() throws PaymentFailedException {
+        PaymentResponse response = new PaymentResponse();
+        // Steps related to rewards card payment like getting current rewards balance, debiting
+        // balance etc.
+        System.out.println("Updating rewards balance");
+        response.setIdentifier(cardNumber);
+        return response;
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/model/PaymentGatewayResponse.java

@@ -0,0 +1,16 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.model;
+
+public class PaymentGatewayResponse {
+    String fingerprint;
+
+    public PaymentGatewayResponse() {
+    }
+
+    public String getFingerprint() {
+        return fingerprint;
+    }
+
+    public void setFingerprint(String fingerprint) {
+        this.fingerprint = fingerprint;
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/model/PaymentResponse.java

@@ -0,0 +1,16 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.model;
+
+public class PaymentResponse {
+    String identifier;
+
+    public PaymentResponse() {
+    }
+
+    public String getIdentifier() {
+        return identifier;
+    }
+
+    public void setIdentifier(String identifier) {
+        this.identifier = identifier;
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/paymentgateway/IPaymentGatewayHandler.java

@@ -0,0 +1,8 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.paymentgateway;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.model.PaymentGatewayResponse;
+
+public interface IPaymentGatewayHandler {
+    PaymentGatewayResponse handlePayment() throws PaymentFailedException;
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/paymentgateway/PaymentGatewayHandler.java

@@ -0,0 +1,34 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.paymentgateway;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentFailedException;
+import io.reflectoring.solid.lsp.paymentexample.common.external.PaymentGateway;
+import io.reflectoring.solid.lsp.paymentexample.redesigned.model.PaymentGatewayResponse;
+import java.util.Date;
+
+public class PaymentGatewayHandler implements IPaymentGatewayHandler {
+    String name;
+    String cardNumber;
+    String verificationCode;
+    Date expiryDate;
+    PaymentGateway gateway = new PaymentGateway();
+
+    public PaymentGatewayHandler(String name, String cardNumber, String verificationCode, Date expiryDate) {
+        this.name = name;
+        this.cardNumber = cardNumber;
+        this.verificationCode = verificationCode;
+        this.expiryDate = expiryDate;
+    }
+
+    @Override
+    public PaymentGatewayResponse handlePayment() throws PaymentFailedException {
+        // send details to payment gateway (PG) and save the fingerprint
+        // received from PG
+        System.out.println("Sending details to payment gateway");
+        String fingerprint = gateway.process(name, cardNumber, verificationCode, expiryDate);
+        PaymentGatewayResponse pgResponse = new PaymentGatewayResponse();
+        pgResponse.setFingerprint(fingerprint);
+        System.out.println("Payment gateway response received");
+
+        return pgResponse;
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/validators/BankCardBasicValidator.java

@@ -0,0 +1,27 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.validators;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+import java.util.Date;
+
+public class BankCardBasicValidator implements IPaymentInstrumentValidator {
+    String name;
+    String cardNumber;
+    String verificationCode;
+    Date expiryDate;
+
+    public BankCardBasicValidator(String name, String cardNumber, String verificationCode, Date expiryDate) {
+        this.name = name;
+        this.cardNumber = cardNumber;
+        this.verificationCode = verificationCode;
+        this.expiryDate = expiryDate;
+    }
+
+    @Override
+    public void validate() throws PaymentInstrumentInvalidException {
+        // basic validation on name, expiryDate etc.
+        if (name == null || name.isEmpty()) {
+            throw new PaymentInstrumentInvalidException("Name is invalid");
+        }
+        // other basic validations
+    }
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/redesigned/validators/IPaymentInstrumentValidator.java

@@ -0,0 +1,7 @@
+package io.reflectoring.solid.lsp.paymentexample.redesigned.validators;
+
+import io.reflectoring.solid.lsp.paymentexample.common.exceptions.PaymentInstrumentInvalidException;
+
+public interface IPaymentInstrumentValidator {
+    void validate() throws PaymentInstrumentInvalidException;
+}

solid/lsp/src/main/java/io/reflectoring/solid/lsp/paymentexample/violation/instruments/RewardsCard.java

@@ -0,0 +1,11 @@
+package io.reflectoring.solid.lsp.paymentexample.violation.instruments;
+
+import io.reflectoring.solid.lsp.paymentexample.common.instruments.PaymentInstrument;
+import java.util.Date;
+
+public class RewardsCard extends PaymentInstrument {
+    public RewardsCard(String name, String cardNumber, String verificationCode, Date expiryDate) {
+        // Reward cards don't have verification code and expiry date, so we are forced to pass null
+        super(name, cardNumber, null, null);
+    }
+}

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

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.0.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists