背景，在Action中發送郵件，阻塞程序繼續執行並返回500，使用 Thread 實現非同步發送，因為我們並不關心郵件是否到達,只需正常發送即可。

		
	public String execute(){
	
		...
		...
		
			try {
				// Send email
				
				Thread sendmail = new Thread(new Runnable() {
					@Override
					public void run() {
						try {
							log.info("sendEmail Begin");
							sender.sendEmail(form.getEmail(), form.getText());
							log.info("sendEmail End");
						} catch (Exception e) {
							e.printStackTrace();
						}
					}
				});
				sendmail.setName("sendmail" + sendmail.getId() + "logingName:" + form.getLoginname());
				sendmail.start();
				
			} catch (Exception e) {
				e.printStackTrace();
				log.info("sendEmail Error");
			}

			...
			...
			
			log.info("CreateTrialAccount:" + form.toString());
			return Action.SUCCESS;
	}