Java 引发异常时EDT是否重新启动？

（下面的示例代码是自包含且可运行的，您可以尝试，它不会使您的系统崩溃：）

Tom Hawtin在这里对这个问题发表了评论：

即：

EDT不太可能崩溃。EDT调度中抛出的未经检查的异常被捕获、转储，线程继续运行

有人能解释一下这是怎么回事吗（每次你点击“抛出一个未检查的异常”按钮时，都会故意执行除以零的操作）：

我得到以下信息（这是我所期望的）：

对我来说，这是一个未经检查的例外，对吗

您可以看到，每次触发崩溃时，线程ID都会增加

那么，EDT是在每次抛出未经检查的异常时自动重新启动，还是像Tom Hawtin评论的那样，未经检查的异常“被捕获、转储并且线程继续”呢

---

这是怎么回事？

有趣的问题。我本以为异常被捕获了，线程还在继续，但经过一些研究，我不太确定

我扩展了你的程序

Set<Thread> seenAwtThreads = new HashSet<Thread>();

完整运行方法的实现如下所示：

public void run() {
    try {
        pumpEvents(new Conditional() {
            public boolean evaluate() {
                return true;
            }
        });     
    } finally {
        /*
         * This synchronized block is to secure that the event dispatch 
         * thread won't die in the middle of posting a new event to the
         * associated event queue. It is important because we notify
         * that the event dispatch thread is busy after posting a new event
         * to its queue, so the EventQueue.dispatchThread reference must
         * be valid at that point.
         */
        synchronized (theQueue) {
            if (theQueue.getDispatchThread() == this) {
                theQueue.detachDispatchThread();
            }
            /*
             * Event dispatch thread dies in case of an uncaught exception. 
             * A new event dispatch thread for this queue will be started
             * only if a new event is posted to it. In case if no more
             * events are posted after this thread died all events that 
             * currently are in the queue will never be dispatched.
             */
            /*
             * Fix for 4648733. Check both the associated java event
             * queue and the PostEventQueue.
             */
            if (theQueue.peekEvent() != null || 
                !SunToolkit.isPostEventQueueEmpty()) { 
                theQueue.initDispatchThread();
            }
            AWTAutoShutdown.getInstance().notifyThreadFree(this);
        }
    }
}

---

例如，线程ID在我的平台上保持不变。中讨论的净效果是“当至少有一个可显示的组件时，JVM将不会退出。”

事件调度线程上有一个默认设置，它将异常打印到System.out，然后在线程中继续。

另一个有趣的注意事项是：不必使用Math.abs（0）来“把戏“让编译器接受它。0/0是一个ok表达式，也会引发异常@他，他，我知道，我知道，我看过那个讨论。。。但如果你写了0/0或1/0，那么人们会问它，它甚至在编译：）哈哈哈。。。好的方面：-）查看

EventDispatchThread.pumpOneEventForFilters

，在当前的实现中，“它很复杂”。显然，不同的实现可能会有所不同。在EDT退出之前，当没有实现windows时，可能总是捕捉到异常。@垃圾神：到目前为止，我只在Debian Linux系统上尝试过：）+1，这个链接非常棒！是 啊我在ubuntu上使用Java6。你在哪个系统上使用垃圾神？@NoozNooz42:虽然Mac OS X保持相同的ID，但我看到你在Ubuntu 10.04上报告的增量。@Trashgood:是的，刚刚在OS X 10.4/Tiger/Java 1.5和OS X 10.6/Snow Leopard/Java 1.6上试用过，两个ID都保持不变。我认为在操作系统X上，在按钮释放之后，按钮没有被正确地重新绘制（在崩溃之后，就像鼠标释放事件丢失一样），而在Linux上，按钮释放被正确地考虑到了（不确定是这样说的）。@NoozNooz42：我在Mac OS X 10.5.8和Ubuntu 10.04上都使用了Java 1.6。eMac的来源和@aioobe显示的相同。@NoozNooz42，不，我想是6。如果您发现它在java 7中发生了更改，请告诉我：-）很抱歉延迟回复。我在MacOSX10.5.8和Ubuntu 10.04上都使用了Java1.6。Mac源与您显示的源相同。

Set<Thread> seenAwtThreads = new HashSet<Thread>();

/*
 * Event dispatch thread dies in case of an uncaught exception. 
 * A new event dispatch thread for this queue will be started
 * only if a new event is posted to it. In case if no more
 * events are posted after this thread died all events that 
 * currently are in the queue will never be dispatched.
 */

public void run() {
    try {
        pumpEvents(new Conditional() {
            public boolean evaluate() {
                return true;
            }
        });     
    } finally {
        /*
         * This synchronized block is to secure that the event dispatch 
         * thread won't die in the middle of posting a new event to the
         * associated event queue. It is important because we notify
         * that the event dispatch thread is busy after posting a new event
         * to its queue, so the EventQueue.dispatchThread reference must
         * be valid at that point.
         */
        synchronized (theQueue) {
            if (theQueue.getDispatchThread() == this) {
                theQueue.detachDispatchThread();
            }
            /*
             * Event dispatch thread dies in case of an uncaught exception. 
             * A new event dispatch thread for this queue will be started
             * only if a new event is posted to it. In case if no more
             * events are posted after this thread died all events that 
             * currently are in the queue will never be dispatched.
             */
            /*
             * Fix for 4648733. Check both the associated java event
             * queue and the PostEventQueue.
             */
            if (theQueue.peekEvent() != null || 
                !SunToolkit.isPostEventQueueEmpty()) { 
                theQueue.initDispatchThread();
            }
            AWTAutoShutdown.getInstance().notifyThreadFree(this);
        }
    }
}