public void addShutdownHook(Thread hook)

爲JVM關閉時添加鉤子，可以用來做一些日誌處理，清理內存數據，保存內存數據等操作

   public void addShutdownHook(Thread hook) {
	SecurityManager sm = System.getSecurityManager();
	if (sm != null) {
	    sm.checkPermission(new RuntimePermission("shutdownHooks"));
	}
	ApplicationShutdownHooks.add(hook);
    }

 

源碼如下，可以添加多個鉤子，當JVM結束時會一一調用。如下

 Runtime.getRuntime().addShutdownHook(shutdownHook);