Question

我运行代码时遇到此异常。即使代码运行正常，我在终端上也会遇到一些例外

Exception in thread "AWT-EventQueue-1" java.lang.IllegalThreadStateException
    at java.lang.Thread.start(Thread.java:708)
    at SR.start(SR.java:38)
    at SR.mouseClicked(SR.java:212)
    at java.awt.Component.processMouseEvent(Component.java:6536)
    at java.awt.Component.processEvent(Component.java:6298)
    at java.awt.Container.processEvent(Container.java:2236)
    at java.awt.Window.processEvent(Window.java:2025)
    at java.awt.Component.dispatchEventImpl(Component.java:4889)
    at java.awt.Container.dispatchEventImpl(Container.java:2294)
    at java.awt.Window.dispatchEventImpl(Window.java:2746)
    at java.awt.Component.dispatchEvent(Component.java:4711)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
    at java.awt.EventQueue.access$500(EventQueue.java:97)
    at java.awt.EventQueue$3.run(EventQueue.java:709)
    at java.awt.EventQueue$3.run(EventQueue.java:703)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:90)
    at java.awt.EventQueue$4.run(EventQueue.java:731)
    at java.awt.EventQueue$4.run(EventQueue.java:729)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:80)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
    at org.GNOME.Accessibility.AtkWrapper$5.dispatchEvent(AtkWrapper.java:700)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)

我做错了什么？

我的start()方法

private void start() throws IllegalStateException {
    if (HelperThread == null)
        HelperThread = new Thread(this);
    HelperThread.start();
}

Answer 1

您似乎开始使用相同的Thread两次，这是不允许的。

如果您希望重复使用同一个帖子，我建议您改为创建ExecutorService。

Answer 2

问题是如果HelperThread不为null（它已经存在）并且你调用HelperThread.start（）则尝试启动（）一个已经启动或完成它处理的线程。如果要重新启动处理，则必须先停止该线程。要优雅地执行此操作，请在实际线程中使用while（running）{}模式。然后，在start（） - 方法中，将标志设置为false，等待线程死亡，然后启动一个新线程：

private void start() throws IllegalStateException {
    if (HelperThread != null) {
        running = false;
        HelperThread.join(); // wait for it to die...
    }

    // Start fresh...
    HelperThread = new Thread(this);
    HelperThread.start();
}

另外，作为旁注，请避免使用大写字母作为变量的第一个字母。它应该是“helperThread”。

java中的非法状态异常

2 个答案: