Add classpath in manifest using Gradle

Question

I would like my Gradle build script to add the complete Classpath to the manifest file contained in JAR file created after the build.

Example:

Manife         


        

Answer 1

Found a solution on Gradle's forum:

jar {
  manifest {
    attributes(
      "Class-Path": configurations.compile.collect { it.getName() }.join(' '))
  }
}

Source: Manifest with Classpath in Jar Task for Subprojects

Answer 2

I managed to create a custom Jar file with its own manifest file like so:

task createJar(type : Jar) {
    manifest {
        attributes(
            'Manifest-Version': "1.0",
            'Main-Class': "org.springframework.boot.loader.JarLauncher",
            'Start-Class': "com.my.app.AppApplication",
            'Spring-Boot-Version': "2.2.4.RELEASE",
            'Spring-Boot-Classes': "BOOT-INF/classes/",
            'Spring-Boot-Lib': "BOOT-INF/lib/"
        )
    }
    def originDir = file("${buildDir}/unpacked")
    def destinationFile = "${buildDir}/repackaged/${project.name}-${version}"
    entryCompression ZipEntryCompression.STORED // no compression in case there are files in BOOT-INF/lib
    archiveName destinationFile
    from originDir
    archiveFile
}

Answer 3

If your project has external library dependencies, you could copy the jars to a folder and add the classpath entries in the manifest.

 def dependsDir = "${buildDir}/libs/dependencies/"
    task copyDependencies(type: Copy) {
    from configurations.compile
    into "${dependsDir}"
   }
task createJar(dependsOn: copyDependencies, type: Jar) {
  
    manifest {
        attributes('Main-Class': 'com.example.gradle.App',
                'Class-Path': configurations.compile.collect { 'dependencies/' + it.getName() }.join(' ')
        )
    }
    with jar
}

More details can be read here