[求助]创建的类为什么也有错?

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class c11_6 extends JApplet
{
int x,y;
JLabel lb1=new JLabel("x"),lb2=new JLabel("y"),lb3=new JLabel("");
JTextField tf1=new JTextField(5),tf2=new JTextField(5);
Container cp=getContentPane();
FlowLayout flow=new FlowLayout(FlowLayout.CENTER,5,5);
public void init()
{
cp.setLayout(flow);
cp.add(lb1);
cp.add(tf1);
cp.add(lb2);
cp.add(tf2);
cp.add(lb3);
addMouseListener(new mouseListener());
addMouseMotionListener(new koLis());
}
class mouseListener implements MouseListener//这里创建的类为什么会有错呢?
{
public void mouseClicked(MouseEvent e)
{lb3.setText("点击鼠标");}
public void mousePressed(MouseEvent e)
{lb3.setText("鼠标按钮按下");}
public void mouseEntered(MouseEvent e)
{lb3.setText("鼠标进入窗口");}
}
class koLis implements MouseMotionListener
{
public void mouseMoved(MouseEvent e)
{
x=e.getX();//返回发生鼠标事件的X坐标
y=e.getY();
tf1.setText(String.valueOf(x));//返回当前字符串
tf2.setText(String.valueOf(y));
}
public void mouseDragged(MouseEvent e)
{lb3.setText("拖动鼠标");}

}
}
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你没覆盖掉mouseExit方法
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mouseReleased方法也要覆盖
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成员函数还要全部包括啊?想简单点试下这个程序,少写了点就不行了!

----------------解决方案--------------------------------------------------------
class mouseListener implements MouseListener
改成:
class mouseListener extends MouseAdapter
就可以不用全覆盖了了;
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那你帮我讲讲这里面的区别呗?
----------------解决方案--------------------------------------------------------
class mouseListener extends MouseAdapter
是继承类;
根上面的不一样;
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我知道啊,上面的是接口,那接口就全部要写全啊?
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如果你的类实现了一个接口，那你的类里面必须覆盖所有接口的方法，少一个都不行

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兄弟,我给你投了票

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