后台创建窗体下拉列表

<pre name="code" class="html"><strong>创建一个窗体，上面有两个下拉列表，一个为学院下拉列表，一个为专业下拉列表，
要求用户选择某个院系以后，专业下拉列表中的选项相应进行更新。
软件学院：软件开发，软件测试，网络工程
外语学院:英语，日语，法语
管理学院：工商管理，会计，市场营销</strong>

package cn.cw.gps.domain;

import java.awt.Container;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Toolkit;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;

import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class zuoye2 extends JFrame{
private JComboBox xyJComboBox,zyJComboBox;
private String xyName[]={"软件学院","外语学院","管理学院"};
private String zyName[][]={{"软件开发","软件测试","网络工程"},{"英语","日语","法语"},{"工商管理","会计","市场营销"}};
public zuoye2(){
Toolkit toolkit = Toolkit.getDefaultToolkit();
Dimension dimension = toolkit.getScreenSize();
setBounds(dimension.width/4,dimension.height/4,dimension.width/4,dimension.height/4);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

xyJComboBox = new JComboBox(xyName);
zyJComboBox = new JComboBox(zyName[0]);

Container container = this.getContentPane();
container.setLayout(new FlowLayout());
container.add(new JLabel("学院"));
container.add(xyJComboBox);
container.add(new JLabel("专业"));
container.add(zyJComboBox);

xyJComboBox.addItemListener(new ItemListener() {

public void itemStateChanged(ItemEvent e) {
// TODO Auto-generated method stub
zyJComboBox.removeAllItems();
int index = xyJComboBox.getSelectedIndex();
for(int i=0;i<zyName[index].length;i++){
zyJComboBox.addItem(zyName[index][i]);
}
}
});
setVisible(true);
}

public static void main(String[] args) {
zuoye2 z = new zuoye2();
}
}