Task Execution

In Same Thread

To run a task in the current thread, you do this: 

Callable<String> mytask = new MyTask();
String result = TaskExecutor.execute(mytask);

In New Thread

To run a task in a new thread, and block this thread until the task is complete, you do this: 

Callable<String> mytask = new MyTask();
TaskFuture<String> future = TaskExecutor.start(mytask);
String result = future.get();

When started that way, the task can be easily stopped: 

Callable<String> mytask = new Tasks.MyTask();
TaskFuture<String> future = TaskExecutor.start(mytask);
// logic that decides to stop the task
future.cancel(true);

Alternatively, if the task supports pausing, it can be paused and restarted as follows: 

Callable<String> mytask = new Tasks.MyTask();
TaskFuture<String> future = TaskExecutor.start(mytask);
// logic that decides to pause the task
future.pause();
// logic that decides when to restart the task
future.unpause();

Advanced

More advanced control over how tasks are set up and started, can be obtained via use of the prepare() method. This allows you to control the state of the task or tasks prior to starting execution.

This prepares a task for synchronous (same thread) execution and then starts it running and gets its result: 

Callable<String> mytask = new Tasks.MyTask();
StartableTaskFuture<String> startableFuture =
    TaskExecutor.prepare(false, "MyThread1", mytask);
    
// execute immediately in current thread
TaskFuture<String> future = startableFuture.start();

// fetch already available result
String result = future.get();

This prepares a task for asynchronous (separate thread) execution and then starts it running and waits for its result: 

Callable<String> mytask = new Tasks.MyTask();
StartableTaskFuture<String> startableFuture =
    TaskExecutor.prepare(true, "MyThread1", mytask);
    
// start off a new thread
TaskFuture<String> future = startableFuture.start();

// blocks until complete
String result = future.get();

The following example performs a "gunshot" start of the tasks, executing them asynchronously. The call to prepare() creates the Thread object and executes any @Init methods: 

List mytasks = new ArrayList();
List startableFutures =
    new ArrayList();

for (Callable<String> task: mytasks) {
  StartableTaskFuture<String> future = TaskExecutor.prepare(true, task);
  startableFutures.add(future);
}

for (StartableTaskFuture<String> future: startableFutures) {
  future.start();
}