小编SS1*_*149的帖子

每次使用类名创建一个新对象时,我都会收到此错误:

"无法实例化Type Main"

这是代码:

import javax.swing.*;
import java.util.Scanner;
import java.applet.Applet;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.geom.Ellipse2D;

public abstract class Main extends JPanel implements ActionListener, KeyListener{

Timer t = new Timer(5, this);
double x = 0, y = 0, velX = 0, velY = 0;

public Main() {
    t.start();
    addKeyListener(this);
    setFocusable(true);
    setFocusTraversalKeysEnabled(false);

}

public void paintComponent(Graphics g) {
    super.paintComponent(g);
    Graphics2D g2 = (Graphics2D) g;
    g2.fill(new Ellipse2D.Double(x, y, 40, 40));
    }

public void actionPerformed(ActionEvent e) { …