workerApi.gradle

// Creaate an implementation of the task using all of the types below
task reverseFiles(type: ReverseFiles) {
    outputDir = file("$buildDir/reversed")
    source("sources")
}

// The parameters for a single unit of work
interface ReverseParameters extends WorkParameters {
    RegularFileProperty getFileToReverse()
    DirectoryProperty getDestinationDir()
}

// The implementation of a single unit of work.
abstract class ReverseFile implements WorkAction<ReverseParameters> {
    private final FileSystemOperations fileSystemOperations

    @Inject
    public ReverseFile(FileSystemOperations fileSystemOperations) {
        this.fileSystemOperations = fileSystemOperations
    }

    @Override
    void execute() {
        fileSystemOperations.copy {
            from parameters.fileToReverse
            into parameters.destinationDir
            filter { String line -> line.reverse() }
        }
    }
}

class ReverseFiles extends SourceTask {
    private final WorkerExecutor workerExecutor

    @OutputDirectory
    File outputDir

    // The WorkerExecutor will be injected by Gradle at runtime
    @Inject
    ReverseFiles(WorkerExecutor workerExecutor) {
        this.workerExecutor = workerExecutor
    }

    @TaskAction
    void reverseFiles() {
        // Create a WorkQueue to submit work items
        WorkQueue workQueue = workerExecutor.noIsolation()

        // Create and submit a unit of work for each file
        source.each { file ->
            workQueue.submit(ReverseFile.class) { ReverseParameters parameters ->
                parameters.fileToReverse = file
                parameters.destinationDir = outputDir
            }
        }
    }
}