Java ѧÉú¹ÜÀíϵͳ´úÂë

//³õѧJAVA  ¿ª·¢ÁËÒ»¸ö ѧÉú¹ÜÀí³ÌÐò£¬ÄóöÀ´É¹É¹£¬ÒÔ±ã´ó¼Ò²Î¿¼»òÆÀÂÛ Ö¸³ö²»×ãÖ®´¦£¡Ð»Ð» ÓÉÓÚ´Ë´¦²»ÄÜÉÏ´«ÕÕƬ£¬¹Ê·ÅÔÚÎÒµÄÏà
//²áÀïÃæ
//Õâ¸öµÇÈë½çÃæµÄ³ÌÐò£º
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;
import java.util.*;
import java.util.jar.JarFile;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
public class Denglujiemian extends Frame implements ActionListener {
 JLabel JLUserName = new JLabel("Óû§Ãû£º");
 JLabel JLPaw = new JLabel("ÃÜÂë");
 JTextField JTUserName = new JTextField();
 JPasswordField JPsw= new JPasswordField();
 JButton JB1 = new JButton("µÇÈë");
 JButton JB2 = new JButton("È¡Ïû");
 JLabel JL1 = new JLabel("Éí·Ý");
 JComboBox JC = new JComboBox();
 
 
 public Denglujiemian(){
  this.setTitle("ѧÉúÐÅÏ¢¹ÜÀíϵͳ");
  this.setLayout(null);
  JLUserName.setBounds(100,40,100,20);
  this.add(JLUserName);
  JTUserName.setBounds(200, 40, 80, 20);
  this.add(JTUserName);
  JLPaw.setBounds(100, 100, 60, 20);
  this.add(JLPaw);
  JPsw.setBounds(200, 100, 80, 20);
  this.add(JPsw);
  JL1.setBounds(100, 150, 60, 20);
  this.add(JL1);
  JC.setBounds(200, 150, 80, 20);
  this.add(JC);
  JC.addItem(new String("ѧÉú"));
  JC.addItem(new String("ÀÏʦ"));
 
  JB1.setBounds(100, 200, 60, 20);
  this.add(JB1);
  JB1.addActionListener(this);
 
 
 
  JB2.setBounds(200, 200, 60, 20);
  this.add(JB2);
  JB2.addActionListener(this);
 
  this.setVisible(true);
  this.setBounds(400, 250, 400, 250);
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