Thread executer

Question

i have a list of task that is currently running sequentially.
each task is independent of one another.
what i want to do is to execute these tasks in threads (each task run in a thread)
but i want to limit the number of thread running (ie. only five thread may running..when one is finished, another thread may start running untill all thread in a list is done)
Is there some class that let me do this?
if there isn't any, can someone tell me what this thread problem be called (ie..countdown latch, blocking queue)
so i can google and try to implement it

Answer 1

You can try things like.
        ExecutorService executor = Executors.newFixedThreadPool(5);
        Future future = executor.submit(new Runnable() {
            public void run() {
        future.get();
        Future<String> futureCall = executor.submit(new Callable<String>() {
            public String call() throws Exception {
                return "Hello world";
        String result = futureCall.get();