Question

我在一些教程中找到了两个简单的类：

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

和

package Skeleton;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;

import java.awt.Toolkit;
import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import javax.swing.ImageIcon;
import javax.swing.JPanel;
import javax.swing.Timer;

public class Board extends JPanel 
    implements ActionListener {

    private final int B_WIDTH = 350;
    private final int B_HEIGHT = 350;
    private final int INITIAL_X = -40;
    private final int INITIAL_Y = -40;
    private final int DELAY = 25;

    private Image star;
    private Timer timer;
    private int x, y;

    public Board() {

        loadImage();
        initBoard();        
    }

    private void loadImage() {

        ImageIcon ii = new ImageIcon("star.png");
        star = ii.getImage();        
    }

    private void initBoard() {

        setBackground(Color.BLACK);
        setPreferredSize(new Dimension(B_WIDTH, B_HEIGHT));

        setDoubleBuffered(true);

        x = INITIAL_X;
        y = INITIAL_Y;

        timer = new Timer(DELAY, this);
        timer.start();
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);

        drawStar(g);
    }

    private void drawStar(Graphics g) {

        Graphics2D g2d = (Graphics2D) g;
        g2d.drawImage(star, x, y, this);
        Toolkit.getDefaultToolkit().sync();
        g.dispose();        
    }

    @Override
    public void actionPerformed(ActionEvent e) {

        x += 1;
        y += 1;

        if (y > B_HEIGHT) {

            y = INITIAL_Y;
            x = INITIAL_X;
        }

        repaint();  
    }
}

这应该是动画的东西，但编译代码会给我一个错误：

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)

出了什么问题？尽管已经成功编写，但没有任何反应。

Answer 1

检查每个班级的第一行是否有错误。一个类是在＆＃34; Skeleton＆＃34;中，另一个是＆＃34; skeleton＆＃34;。它区分大小写。

线程“AWT-EventQueue-0”中的异常 - 无法编译的源代码？

1 个答案: