Question

java程序编译的时候显示Greating不是抽象的且未覆盖Runnable中的run()，大神帮我找一下错在哪

import java.awt.*;
import javax.swing.*;
import java.util.*;

public class Greeting extends JFrame implements Runnable
{
Thread t1, t2;
int x1=0,x2=0;
public Greeting()
{
t1 = new Thread(this);
t2 = new Thread(this);
t1.start();
t2.start();
}
public void paint(Graphics g)
{
super.paint( g );

g.fillRect(0,50,30,30);
g.fillRect(0,80,30,30);
}

public void run(Graphics g)
{
super.paint( g );
try
{
while(true)
{
if(Thread.currentThread()==t1)
{
g.fillRect(x1++,50,30,30);

Thread.sleep(1000);
repaint();
}
else if(Thread.currentThread()==t2)
{
g.fillRect(x2++,80,30,30);

Thread.sleep(1000);
repaint();
}
}
}
catch(InterruptedException e){}
}

public static void main(String args[])
{
Greeting gre = new Greeting();
}
}

Answer 1

Runnable中的run()是没有参数的，你这个有参数的是重载，并不是覆盖，因为Runnable是接口，你必须覆盖无参的run()

追问

那我要怎么实现g.fillRect