Ive programmed an application that moves an Image when the right arrow or left arrow is pressed,But when this is done the image moves and leavs a ghost of it behind it.So when i am playing the app and press the right arrow it moves and leaves a bit of the image behind it,can someone help me fix this problem.

import java.awt.*;
import javax.swing.*;
import java.io.*;
import java.awt.event.*;
import java.net.*;

public class main extends JFrame implements KeyListener {
String path1 = "move.png";
String path2 = "x.gif";

ImageIcon idle = new ImageIcon(getClass().getResource(path2)) ;
ImageIcon move = new ImageIcon(path1) ;
ImageIcon bullet = new ImageIcon("b.png") ;
//Icon bug = new ImageIcon( getClass().getResource( "bug1.gif" ) );

//postion of ship
int x= 50;
int y = 50;

//default size of ship
int bull = 0;//0 if bullet is not being fierd 1 if it is

int im= 1; //0 means ship is moving 1 means ship is idle
public main(){
super("Astroids");


//Window Properites
setVisible(true);
setSize(500,500);
addKeyListener(this);
}

public void keyReleased(KeyEvent e) {

if(e.getKeyCode() == 39){

im = 1;

}

if(e.getKeyCode() == 37){
System.out.println("left");


im = 1;

}
if(e.getKeyCode() == 32){
System.out.println("bang");
bull = 1;//fire

}
}

public void keyPressed(KeyEvent e) {
System.out.println(e.getKeyCode());

if(e.getKeyCode() == 39){

right();
}

if(e.getKeyCode() == 37){
left();
}
}

public void right(){
System.out.println("right");

x = x + 10;
im = 0;
update();
}

public void left(){
System.out.println("left");

x = x - 10;
im = 0;
update();
}



public void keyTyped(KeyEvent e) {

}


public void update() {
try {
Thread.sleep(20); // sleep a bit
}
catch(InterruptedException ex){}

repaint();

}


public void paint(Graphics g){
super.paint(g);





g.drawImage(idle.getImage(),x,y,this);

}


public static void main(String[] args){

main app = new main();
}
}