执行主线程之后又执行了几个子线程，保证子线程执行完成在结束主线程

这是因为一个坑：主线程执行结束了，子线程还没有结束就直接return了

@RequestMapping(value = "/return", method = RequestMethod.POST)    private JsonResult returnDeposit(@RequestBody Map<String, Object> params) {     //新建一个线程池 ExecutorService cachedThreadPool = Executors.newCachedThreadPool();CountDownLatch cdl = new CountDownLatch(2);//这个数量写你新建子线程的数量cachedThreadPool.execute(new Runnable() {                 @Override                 public void run() {                     logger.info("第一个线程");                     //完成，计数器减一                      cdl.countDown();                  }                 }); cachedThreadPool.execute(new Runnable() {                 @Override                 public void run() {                     logger.info("第2个线程");                     //完成，计数器减一                      cdl.countDown();                  }                 });//等子线程执行完                 try {                    cdl.await();                } catch (Exception e) {                    logger.error(e.toString());                }             cachedThreadPool.shutdown();     return new JsonResult(ResultCode.SUCCESS,"成功"); }