Java “线程中的异常”；AWT-EventQueue-0“事件队列”不可编译源代码？

我在一些教程中发现了两个简单的类：

package skeleton;

import java.awt.EventQueue;
import javax.swing.JFrame;

public class Skeleton extends JFrame 
{

    public Skeleton() 
    {
        add(new Board());

        setTitle("Star");
        pack();
        setResizable(false);
        setLocationRelativeTo(null);        
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) 
    {
        EventQueue.invokeLater(new Runnable() {            
            @Override
            public void run() {
                JFrame ex = new Skeleton();
                ex.setVisible(true);             
            }
        });
    }

} // End Skeleton

及

这应该是动画的东西，但编译代码给我一个错误：

run:
Exception in thread "AWT-EventQueue-0" java.lang.RuntimeException: Uncompilable source code - Erroneous tree type: <any>
    at skeleton.Skeleton.<init>(Skeleton.java:11)
    at skeleton.Skeleton$1.run(Skeleton.java:25)
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:705)
    at java.awt.EventQueue.access$000(EventQueue.java:101)
    at java.awt.EventQueue$3.run(EventQueue.java:666)
    at java.awt.EventQueue$3.run(EventQueue.java:664)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:675)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
BUILD SUCCESSFUL (total time: 1 second)

运行：
线程“AWT-EventQueue-0”java.lang.RuntimeException中的异常：不可编译的源代码-错误的树类型：
位于skeleton.skeleton.（skeleton.java:11）
在skeleton.skeleton$1.run（skeleton.java:25）
在java.awt.event.InvocationEvent.dispatch（InvocationEvent.java:251）中
位于java.awt.EventQueue.dispatchEventImpl（EventQueue.java:705）
在java.awt.EventQueue.access$000（EventQueue.java:101）
在java.awt.EventQueue$3.run（EventQueue.java:666）
在java.awt.EventQueue$3.run（EventQueue.java:664）
位于java.security.AccessController.doPrivileged（本机方法）
位于java.security.ProtectionDomain$1.doIntersectionPrivilege（ProtectionDomain.java:76）
位于java.awt.EventQueue.dispatchEvent（EventQueue.java:675）
位于java.awt.EventDispatchThread.pumpOneEventForFilters（EventDispatchThread.java:211）
位于java.awt.EventDispatchThread.PumpeEventsforFilter（EventDispatchThread.java:128）
位于java.awt.EventDispatchThread.PumpeEventsforHierarchy（EventDispatchThread.java:117）
位于java.awt.EventDispatchThread.pumpEvents（EventDispatchThread.java:113）
位于java.awt.EventDispatchThread.pumpEvents（EventDispatchThread.java:105）
在java.awt.EventDispatchThread.run（EventDispatchThread.java:90）
生成成功（总时间：1秒）

---

怎么了？尽管编写了成功的构建，但什么也没有发生。

检查每个类的第一行是否有错误。一个类在包“Skeleton”中，另一个在“Skeleton”中。它是区分大小写的

run:
Exception in thread "AWT-EventQueue-0" java.lang.RuntimeException: Uncompilable source code - Erroneous tree type: <any>
    at skeleton.Skeleton.<init>(Skeleton.java:11)
    at skeleton.Skeleton$1.run(Skeleton.java:25)
    at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251)
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:705)
    at java.awt.EventQueue.access$000(EventQueue.java:101)
    at java.awt.EventQueue$3.run(EventQueue.java:666)
    at java.awt.EventQueue$3.run(EventQueue.java:664)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:675)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:211)
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:128)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:117)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:113)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:105)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:90)
BUILD SUCCESSFUL (total time: 1 second)