文本框和密码的使用

package wo;import java.awt.*;import java.awt.event.*;import javax.swing.*;public class Ex5 implements ActionListener{/** * @param args */JLabel lab1,lab2;JFrame frame;JButton b1,b2;Container con;JTextField use;JPasswordField pass;public void actionPerformed(ActionEvent e){String str;if(e.getSource()==b1){str="你的用户名是"+use.getText()+"\n你的密码是"+new String(pass.getPassword());JOptionPane.showMessageDialog(frame, str);}else if(e.getSource()==b2){pass.setText("");use.setText("");}else if(e.getSource()==use){pass.requestFocus();}else if(e.getSource()==pass){b1.doClick();}}public Ex5(){frame=new JFrame("文本框和密码的使用");con=frame.getContentPane();//加载一个图片lab1=new JLabel("用户名:");lab2=new JLabel("密码:");b1=new JButton("登录");b2=new JButton("取消");b1.addActionListener(this);b2.addActionListener(this);use=new JTextField();use.setColumns(20);use.addActionListener(this);pass=new JPasswordField();pass.setColumns(20);pass.addActionListener(this);con.setLayout(new FlowLayout());con.add(lab1);con.add(use);con.add(lab2);con.add(lab2);con.add(pass);con.add(b1);con.add(b2);frame.setSize(300,300);frame.setVisible(true);frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);}public static void main(String[] args) {// TODO Auto-generated method stubnew Ex5();}}