git.gumartinm.name Git - JavaForFun/blob

   1 package de.test.thread.executor.future;
   2
   3 import java.util.concurrent.Callable;
   4 import java.util.concurrent.ExecutionException;
   5 import java.util.concurrent.Executors;
   6 import java.util.concurrent.ScheduledExecutorService;
   7 import java.util.concurrent.ScheduledFuture;
   8 import java.util.concurrent.TimeUnit;
   9
  10
  11 public class TimerSchedulerExample {
  12         ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor();
  13
  14         public void test() {
  15                 ScheduledFuture<Integer> future = executor.schedule(new Callable<Integer>() {
  16
  17                         @Override
  18                         public Integer call() throws Exception {
  19                                 return 666;
  20                         }
  21
  22                 }, 2000, TimeUnit.MILLISECONDS);
  23
  24                 long delay;
  25                 while ((delay = future.getDelay(TimeUnit.MILLISECONDS)) > 0) {
  26                         System.out.println("Delay: " + delay);
  27                 }
  28
  29                 try {
  30                         Integer result = future.get();
  31                         System.out.println(result);
  32                 } catch (InterruptedException e) {
  33                         Thread.currentThread().interrupt();
  34                 } catch (ExecutionException e) {
  35                         throw launderThrowable(e);
  36                 } finally {
  37                         future.cancel(true);
  38                 }
  39         }
  40
  41
  42     private RuntimeException launderThrowable(final Throwable exception) {
  43         exception.printStackTrace();
  44         if (exception instanceof RuntimeException)
  45             return (RuntimeException) exception;
  46         else if (exception instanceof Error)
  47             throw (Error) exception;
  48         else
  49             throw new IllegalStateException("Not unchecked", exception);
  50     }
  51 }