getImage()的使用方法

[a394513265]

大家帮我看看这个程序 为什么图片不能显示
import java.applet.*;

import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Image;

import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.image.ImageObserver;

import javax.swing.*;
public class Lp_client extends Applet implements ImageObserver{
JLabel label1;
JComboBox jcb;
Color color=Color.red;

Image image,img2;

String[] photoNames={"图书馆","一号教学楼","塑胶操场","南门"};
String place="";


public void init(){
setLayout(new FlowLayout());
label1=new JLabel("请选择");

jcb=new JComboBox(photoNames);
jcb.addItemListener(new NewAction());
add(label1);
add(jcb);




}
class NewAction implements ItemListener{
public void itemStateChanged(ItemEvent e){
place=(String)e.getItem();
if(e.getStateChange()==ItemEvent.SELECTED){
if("图书馆".equals(e.getItem())){
image=getImage(getDocumentBase(),"./1.jpg");



}




else if("南门".equals(e.getItem())){
image=getImage(getDocumentBase(),"./2.jpg");



}
else if("塑胶操场".equals(e.getItem())){
image=getImage(getDocumentBase(),"./3.jpg");


}
else if("一号教学楼".equals(e.getItem())){
image=getImage(getDocumentBase(),"./4.jpg");


}

repaint();

}
}
}
public void paint(Graphics g){
g.drawImage(image, 50, 100, this);

}




}