What is the correct background process behavior for an application other than the Java GUI?

Question

How can a Java command-line application do background work without resources? Should it use sleep () in a loop or is there a more elegant / efficient way?

Answer 1

Some heuristics:

• Do not try to make planning decisions in your application. The operating system scheduler is better than yours. Let him do his job.
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Answer 2

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: myThread.setPriority(Thread.MIN_PRIORITY);

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Answer 3

. ExecutorService... :

ExecutorService service = Executors.newCachedThreadPool();

Callable<Result> task = new Callable<Result>() {
    public Result call() throws Exception {
        // code which will be run on background thread
    }
};

Future<Result> future = service.submit(task);

// Next line wait until background task is complete
// without killing CPU. Of course, you can do something
// different here and check your 'future' later.
//
// Note also that future.get() may throw various exceptions too,
// you'll need to handle them properly

Result resultFromBackgroundThread = future.get();

Java 5, ExecutorService, Callable, Future .. java.util.concurrent.

Answer 4

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