Java多線程(ExecutorService), 等待所有線程執行完畢.

常用的兩種方式:

第一種方式:來自大神cletus的回答, 原文鏈接

1.  
   ExecutorService taskExecutor = Executors.newFixedThreadPool( 4);
2.  
   while(...) {
3.  
   taskExecutor.execute( new MyTask());
4.  
   }
5.  
   taskExecutor.shutdown();
6.  
   try {
7.  
   taskExecutor.awaitTermination(Long.MAX_VALUE, TimeUnit.NANOSECONDS);
8.  
   } catch (InterruptedException e) {
9.  
   ...
10.  
    }

第二種方式:來自大神ChssPly76的回答, 原文鏈接

1.  
   CountDownLatch latch = new CountDownLatch(totalNumberOfTasks);
2.  
   ExecutorService taskExecutor = Executors.newFixedThreadPool( 4);
3.  
   while(...) {
4.  
   taskExecutor.execute( new MyTask());
5.  
   }
6.  
    
7.  
   try {
8.  
   latch.await();
9.  
   } catch (InterruptedException E) {
10.  
    // handle
11.  
    }

然后在線程方法中加入:

1.  
   try {
2.  
   ...
3.  
   } catch (Exception e) {
4.  
   e.printStackTrace();
5.  
   } finally {
6.  
   countDownLatch.countDown();
7.  
   }