Swing常用组件之文本框和文本区

package ch10; 
 
import java.awt.event.*; 
 
import javax.swing.*; 
 
public class LoginTest extends JFrame implements ActionListener 
{ 
  private JPanel jp = new JPanel(); 
  JLabel name = new JLabel("请输入用户名"); 
  JLabel password = new JLabel("请输入密码"); 
  JLabel show = new JLabel(""); 
  private JLabel[] jl = new JLabel[]{name,password,show}; 
  JButton login = new JButton("登录"); 
  JButton reset = new JButton("重置"); 
  private JButton[] jb = new JButton[]{login,reset}; 
  private JTextField jname= new JTextField(); 
  private JPasswordField jpass = new JPasswordField(); 
  public LoginTest() 
  { 
    jp.setLayout(null); 
    for(int i=0;i<2;i++) 
    { 
      jl[i].setBounds(30,20+40*i,180,20); 
      jb[i].setBounds(30+110*i,100,80,20); 
      jb[i].addActionListener(this); 
      jp.add(jl[i]); 
      jp.add(jb[i]); 
    } 
    jname.setBounds(130,15,100,20); 
    jp.add(jname); 
    jname.addActionListener(this); 
    jpass.setBounds(130,60,100,20); 
    jp.add(jpass); 
    jpass.addActionListener(this); 
    jpass.setEchoChar('*'); 
    jl[2].setBounds(10,180,270,20); 
    jp.add(jl[2]); 
    this.add(jp); 
    this.setBounds(200,200,300,300); 
    this.setVisible(true); 
    this.setTitle("登录窗口"); 
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
  } 
  public void actionPerformed(ActionEvent a) 
  { 
    if(a.getSource()==jname) 
    { 
      jpass.requestFocus(); 
    } 
    else if(a.getSource()==jb[1]) 
    { 
      jl[2].setText(""); 
      jname.setText(""); 
      jpass.setText(""); 
      jname.requestFocus(); 
    } 
    else  
    { 
      if(jname.getText().equals("lixiang")&&String.valueOf(jpass.getPassword()).equals("201407239")) 
      { 
        jl[2].setText("登录成功，欢迎您的到来!"); 
      } 
      else 
      { 
        jl[2].setText("对不起，您的密码或用户名错误！"); 
      } 
    } 
  } 
  public static void main(String args[]) 
  { 
    new LoginTest(); 
  } 
} 

JTextArea t1 = new JTextArea();
JTextArea t2 = new JTextArea(2, 8);
JTextArea t3 = new JTextArea("JTextArea3");
JTextArea t4 = new JTextArea("JTextArea4", 5, 10);

import java.awt.*; 
import java.awt.event.*; 
import javax.swing.*; 
 
//实现接口ActionListener 
public class JTextAreaDemo3 implements ActionListener { 
 
  JFrame jf; 
  JPanel jpanel; 
  JButton jb1, jb2, jb3; 
  JTextArea jta = null; 
  JScrollPane jscrollPane; 
 
  public JTextAreaDemo3() { 
 
    jf = new JFrame("JTextArea案例3"); 
    Container contentPane = jf.getContentPane(); 
    contentPane.setLayout(new BorderLayout()); 
 
    jta = new JTextArea(10, 15); 
    jta.setTabSize(4); 
    jta.setFont(new Font("标楷体", Font.BOLD, 16)); 
    jta.setLineWrap(true);// 激活自动换行功能 
    jta.setWrapStyleWord(true);// 激活断行不断字功能 
    jta.setBackground(Color.pink); 
 
    jscrollPane = new JScrollPane(jta); 
    jpanel = new JPanel(); 
    jpanel.setLayout(new GridLayout(1, 3)); 
 
    jb1 = new JButton("复制"); 
    jb1.addActionListener(this); 
    jb2 = new JButton("粘贴"); 
    jb2.addActionListener(this); 
    jb3 = new JButton("剪切"); 
    jb3.addActionListener(this); 
 
    jpanel.add(jb1); 
    jpanel.add(jb2); 
    jpanel.add(jb3); 
 
    contentPane.add(jscrollPane, BorderLayout.CENTER); 
    contentPane.add(jpanel, BorderLayout.SOUTH); 
 
    jf.setSize(400, 300); 
    jf.setLocation(400, 200); 
    jf.setVisible(true); 
 
    jf.addWindowListener(new WindowAdapter() { 
      public void windowClosing(WindowEvent e) { 
        System.exit(0); 
      } 
    }); 
  } 
 
  // 覆盖接口ActionListener的方法actionPerformed 
  public void actionPerformed(ActionEvent e) { 
    if (e.getSource() == jb1) { 
      jta.copy(); 
    } else if (e.getSource() == jb2) { 
      jta.paste(); 
    } else if (e.getSource() == jb3) { 
      jta.cut(); 
    } 
  } 
 
  public static void main(String[] args) { 
    new JTextAreaDemo3(); 
  } 
}