JAVA實(shí)現(xiàn)一個(gè)登錄窗體功能

1、JAVA實(shí)現(xiàn)一個(gè)登錄窗體功能該程序顯示了基于Swing的JFrame的一個(gè)“登錄”窗口。當(dāng)你輸入正確的用戶ID和密碼，你可以得到確認(rèn)，否則你會(huì)被驚動(dòng)由Java標(biāo)準(zhǔn)的消息窗口。在同一時(shí)間的容器和在JPanel的FlowLayout GridLayout的使用Swing的JFrame的1. package com.han; 2.3. import java.awt.Container; 4. import java.awt.FlowLayout; 5. import java.awt.GridLayout; 6. import java.awt.event.ActionEvent; 7. impo

2、rt java.awt.event.ActionListener; 8. import java.util.Arrays; 9.10. import javax.swing.*; 11.12. /* 13. * This program shows a "Login" window based on Swing JFrame. 14. * When you input the correct userID and Password, you can obtain a confirmation, 15. * or else you will be alerted by a J

3、AVA standard message window. 16. * <p> 17. * The Swing JFrame used in the same time the GridLayout for the Container and the FlowLayout for the JPanel. 18. * author han 19. * 20. */ 21. public class SwingJFrameLogin 22. /*define all the necessary member variables*/ 23. String s1=null; 24. char

4、 s2=null; 25. JFrame frame=new JFrame(); 26. Container c=frame.getContentPane(); 27. /*the construct function*/ 28. public SwingJFrameLogin() 29. c.setLayout(new GridLayout(3,1,10,10);/the Container uses the GridLayout for 3 JPanels 30. JPanel panel1=new JPanel(new FlowLayout(FlowLayout.CENTER);/eac

5、h JPanel uses the FlowLayout 31. JPanel panel2=new JPanel(new FlowLayout(FlowLayout.CENTER); 32. JPanel panel3=new JPanel(new FlowLayout(); 33. JLabel label1=new JLabel("用戶名："); 34. final JTextField jt=new JTextField(10); 35. JLabel label2=new JLabel("密碼："); 36. final JPasswordFi

6、eld jp=new JPasswordField(6); 37. jp.setEchoChar(char) 0);/set the display words as visible. 38. final JButton jb1 = new JButton("提交"); 39. final JButton jb2 = new JButton("重置"); 40. panel1.add(label1); 41. panel1.add(jt); 42. panel2.add(label2); 43. panel2.add(jp); 44. panel3.ad

7、d(jb1); 45. panel3.add(jb2); 46. c.add(panel1); 47. c.add(panel2); 48. c.add(panel3); 49. jb1.addActionListener(new ActionListener() 50. Override 51. public void actionPerformed(ActionEvent e) 52. String s1=jt.getText(); 53. char s2=jp.getPassword(); 54. System.out.println(s1); 55. System.out.printl

8、n(s2); 56. char pw='u','p','s' 57. /*System.out.println(Arrays.equals(s2,pw); 58. System.out.println(s1.equals("han");*/ 59. if (s1.equals("han") && Arrays.equals(s2,pw) 60. JOptionPane.showMessageDialog(frame, 61. "登錄成功 ！","Message&

9、quot;,JOptionPane.INFORMATION_MESSAGE); 62. /frame.dispose();（等同于點(diǎn)擊關(guān)閉窗口時(shí)執(zhí)行frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE );） 63. System.exit(0);/正常退出（等同于點(diǎn)擊關(guān)閉窗口時(shí)執(zhí)行frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE );） 64. 65. else 66. JOptionPane.showMessageDialog(frame,/it is a JAVA interna

10、l STD message BOX 67. "You had input a wrong userID !","Warning",JOptionPane.WARNING_MESSAGE); 68. 69. Arrays.fill(s2,'0'); /Zero out the possible password, for security. 70. 71. ); 72. jb2.addActionListener(new ActionListener() 73. Override 74. public void actionPerformed(ActionEvent e) /set all the fields empty. 75. jt.setText(""); 76. jp.setText(""); 77. 78. ); 79. frame.pack();/automatically resize all the components to their preferred sizes. 80.