CodeLift: A Proposed Approach for Seamless Migration to Java 17

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Staying current with platform upgrades is critical for security, performance, and long-term support. With Java 17 as the latest long-term support (LTS) release, your teams gain:

• Stronger security updates
• Improved memory management and garbage collection
• Access to modern APIs and new language features
• Better runtime performance across applications

Java 17 migration process flow

If your applications are still on Java 8 or 11, moving forward may require dependency adjustments and security configuration updates. Without automation, this can quickly become a repetitive and error-prone task. That’s where an automated migration approach can help you accelerate the transition and ensure consistency across repositories.

1. User trigger

You or your team initiate the process by triggering a Jenkins pipeline, either through the UI or via a manual job trigger.

2. Repo cloning and code migration

Jenkins calls the CodeLift utility. Your repository is cloned from GitHub, the utility performs code transformations to update Mule runtime and Java 17, and the migrated code is pushed into a new Git branch for your review and deployment.

3. Artifact retrieval

Jenkins retrieves the migration utility JAR from Nexus (your artifact repository). Java 17–compatible dependencies are tracked in a central database.

4. Logging and audit

Migration details are stored in a database, including:

• Repository name
• Status of migration
• Errors or warnings
• User details

5. Monitoring

You can view migration metrics in a dashboard, including:

• Number of applications migrated
• Success and failure rates
• Migration progress

Putting it into practice: Jenkins pipeline and migration utility

pipeline {  
    agent any
    parameters {
        string(name: 'repository_name', description: 'Name of the Git repository')
        choice(name: 'git_org', description: 'Enter the GitHub Org where the repository exists')
    }

    stages {
        stage('Clone app repository') {
            steps {
                script {
                    repo_name="${params.repository_name}"
                    def GIT_URL = "https://github.com/${params.git_org}/${repo_name}.git"
                    println("Cloning repository from ${GIT_URL}")
                    checkout([
                        $class: 'GitSCM',
                        branches: [[name: "*/master"]],
                        extensions: [[$class: 'RelativeTargetDirectory', relativeTargetDir: "${repo_name}"]],
                        userRemoteConfigs: [[url: "$GIT_URL"]]
                    ])
                }
            }
        }
        stage('Create and push feature branch') {
            steps {
                script {
                    dir("${repo_name}") { 
                        sh 'git checkout -b java17-migration'
                        sh 'git push origin java17-migration'
                    }
                }
            }
        }
        stage('Run migration utility JAR') {
            steps {
                withCredentials([
                    usernamePassword(
                        credentialsId: "DB_Details",
                        usernameVariable: "user",
                        passwordVariable: "pwd"
                )]) {
                    script {
                        sh "java -jar codelift-migration-1.0.0.jar ${params.repository_name} ${params.git_org}"
                    }
                }
            }
        }
        stage('Push migrated branch') {
            steps {
                script {
                    def buildUserId = currentBuild.getBuildCauses()[0].userId
                    dir(repo_name) {
                        sh """
                        git add .
                        git config --global user.email "EMAIL ID"
                        git config --global user.name "USER NAME"
                        git commit -m "Java 17 migration changes initiated by ${buildUserId}"
                        """
                        sh 'git push origin java17-migration'
                        println("Files pushed to repo : ${repo_name} by ${buildUserId}")
                    }    
                }
            }
        }
    }
}

Building the migration utility JAR

Set up project skeleton:

• Use Maven (preferred) or Gradle to initialize your project
• Organize code under src/main/java and src/main/resources

Configuration management: Keep database tables as the source of truth for connector version upgrades

Build the executable JAR: Add a Main class with CLI args (e.g., –repoPath, –dbConfig).
build with Maven:

mvn clean package -DskipTests

The target JAR (codelift-migration-1.0.0.jar) is your deployable artifact.

Publish to repository: