Gradle task to build an OS X app

osxApp.groovy

task osxApp {
    dependsOn jar
    
    doLast {
        def dist = "${buildDir}/app/${project.name}.app"
        mkdir("$dist/Contents/MacOS")
        mkdir("$dist/Contents/Resources")
        ant.copy(file: "src/main/app/Info.plist", todir: "$dist/Contents")
        ant.copy(file: "src/main/app/launcher", todir: "$dist/Contents/MacOS") {
            filterset {
                filter(token: 'APP_JAR', value: "${project.name}-${version}.jar")
                filter(token: 'APP_NAME', value: project.name)
                filter(token: 'JAVA_VERSION', value: jvm_version)
            }
        }
        ant.copy(file: "src/main/app/application.icns", todir: "$dist/Contents/Resources")
        ant.copy(file: "build/libs/${project.name}-${version}.jar", todir: "$dist/Contents/MacOS")
        project.exec {
            commandLine('chmod', '+x', "$dist/Contents/MacOS/launcher")
        }
    }
}