Java多线程(ExecutorService), 等待所有线程执行完毕.

常用的两种方式:

第一种方式:来自大神cletus的回答, 原文链接

ExecutorService taskExecutor = Executors.newFixedThreadPool(4);
while(...) {
  taskExecutor.execute(new MyTask());
}
taskExecutor.shutdown();
try {
  taskExecutor.awaitTermination(Long.MAX_VALUE, TimeUnit.NANOSECONDS);
} catch (InterruptedException e) {
  ...
}

第二种方式:来自大神ChssPly76的回答, 原文链接

CountDownLatch latch = new CountDownLatch(totalNumberOfTasks);
ExecutorService taskExecutor = Executors.newFixedThreadPool(4);
while(...) {
  taskExecutor.execute(new MyTask());
}

try {
  latch.await();
} catch (InterruptedException E) {
   // handle
}

然后在线程方法中加入:

       try {
            ...
        } catch (Exception e) {
            e.printStackTrace();
        }finally {
            countDownLatch.countDown();
        }