Java 无法理解并解决此程序的方法重写错误

错误如下：

import java.awt.*;
import java.awt.event.*;
import javax.swing.*; 
public class test extends JFrame implements MouseListener
{
JFrame f;
JPanel p;
JButton b;
test()
{
    f=new JFrame("My Frame");
    p=new JPanel();
    f.add(p);
    b=new JButton("Button");
    p.add(b);
    f.setSize(100,100);
    f.setVisible(true);
    b.addMouseListener(new MouseListener()
    {
        public void mouseClicked(MouseEvent ae)
        {
            System.out.print("mouse clicked");
        }
    });
    b.addMouseListener(new MouseListener()
    {
        public void mouseEntered(MouseEvent ae)
        {
            System.out.print("mouse Entered");
        }
    });
    b.addMouseListener(new MouseListener()
    {
        public void mouseExited(MouseEvent ae)
        {
            System.out.print("mouse Exited");
        }
    });
    b.addMouseListener(new MouseListener()
    {
        public void mousePressed(MouseEvent ae)
        {
            System.out.print("mouse Pressed");
        }
    });
    b.addMouseListener(new MouseListener()
    {
        public void mouseReleased(MouseEvent ae)
        {
            System.out.print("mouse Released");
        }
    });
}
public static void main(String args[])
{
    new test();
}
}

---

我对AWT不太熟悉，但似乎您有一个非抽象类测试，它没有实现接口MouseListener的抽象方法

您需要实施：

--------------------Configuration: <Default>--------------------
C:\Users\SHUBHENDU\Documents\test.java:19: <anonymous test$1> is not abstract and      does not override abstract method mouseExited(java.awt.event.MouseEvent) in        java.awt.event.MouseListener
        {
        ^
C:\Users\SHUBHENDU\Documents\test.java:26: <anonymous test$2> is not abstract and does not override abstract method mouseExited(java.awt.event.MouseEvent) in java.awt.event.MouseListener
        {
        ^
C:\Users\SHUBHENDU\Documents\test.java:33: <anonymous test$3> is not abstract and does not override abstract method mouseEntered(java.awt.event.MouseEvent) in java.awt.event.MouseListener
        {
        ^
C:\Users\SHUBHENDU\Documents\test.java:40: <anonymous test$4> is not abstract and does not override abstract method mouseExited(java.awt.event.MouseEvent) in java.awt.event.MouseListener
        {
        ^
C:\Users\SHUBHENDU\Documents\test.java:47: <anonymous test$5> is not abstract and does not override abstract method mouseExited(java.awt.event.MouseEvent) in java.awt.event.MouseListener
        {
        ^
5 errors

---

如果你的类是抽象的，你就不需要实现这些方法了，这将由下一个非抽象的子类来完成。

我对AWT不太熟悉，但你似乎有一个非抽象的类测试，它没有实现接口MouseListener的抽象方法

您需要实施：

--------------------Configuration: <Default>--------------------
C:\Users\SHUBHENDU\Documents\test.java:19: <anonymous test$1> is not abstract and      does not override abstract method mouseExited(java.awt.event.MouseEvent) in        java.awt.event.MouseListener
        {
        ^
C:\Users\SHUBHENDU\Documents\test.java:26: <anonymous test$2> is not abstract and does not override abstract method mouseExited(java.awt.event.MouseEvent) in java.awt.event.MouseListener
        {
        ^
C:\Users\SHUBHENDU\Documents\test.java:33: <anonymous test$3> is not abstract and does not override abstract method mouseEntered(java.awt.event.MouseEvent) in java.awt.event.MouseListener
        {
        ^
C:\Users\SHUBHENDU\Documents\test.java:40: <anonymous test$4> is not abstract and does not override abstract method mouseExited(java.awt.event.MouseEvent) in java.awt.event.MouseListener
        {
        ^
C:\Users\SHUBHENDU\Documents\test.java:47: <anonymous test$5> is not abstract and does not override abstract method mouseExited(java.awt.event.MouseEvent) in java.awt.event.MouseListener
        {
        ^
5 errors

---

如果你的类是抽象的，你就不需要实现这些方法了，这将由下一个非抽象的子类来完成。

如果你有一个具体的Java类非抽象类，你必须实现一个接口的所有方法，当然如果你的类实现了这个接口。

---

因此，将MouseListener接口的未实现方法添加到代码中。但每次都会在同一个按钮上添加一个新的鼠标侦听器。这不是它的使用方式。您可以/应该在同一代码体中实现所有MouseListener方法。删除JButton b中多余的MouseListener添加项。

如果您有一个具体的Java类非抽象类，那么您必须实现接口的所有方法，当然，如果您的类实现了该接口。

---

因此，将MouseListener接口的未实现方法添加到代码中。但每次都会在同一个按钮上添加一个新的鼠标侦听器。这不是它的使用方式。您可以/应该在同一代码体中实现所有MouseListener方法。删除JButton b中多余的MouseListener添加项。

如果您只想覆盖MouseListener接口的一种方法，可以使用MouseAdapter，如下所示：

mouseClicked(MouseEvent)    
mouseEntered(MouseEvent)
mouseExited(MouseEvent) 
mousePressed(MouseEvent)    
mouseReleased(MouseEvent)

---

如果您只想覆盖MouseListener接口的一个方法，可以使用MouseAdapter，如下所示：

mouseClicked(MouseEvent)    
mouseEntered(MouseEvent)
mouseExited(MouseEvent) 
mousePressed(MouseEvent)    
mouseReleased(MouseEvent)

要修复这些错误

JButton button = new JButton("Click");
button.addMouseListener(new MouseAdapter() {
    @Override
    public void mouseClicked(MouseEvent e) {
        System.out.println("mouse was clicked");
    }
});

要修复这些错误

JButton button = new JButton("Click");
button.addMouseListener(new MouseAdapter() {
    @Override
    public void mouseClicked(MouseEvent e) {
        System.out.println("mouse was clicked");
    }
});

---

不相关，但您的类名应该大写，以免与方法混淆。公共类testnotrelated，但是您的类名应该大写，这样就不会与方法混淆。公共类Testthanx buddy也很有用：thanx buddy也很有用：