Swing接收用户输入，以#号结束，输出按字典次序最小的字符

Swing接收用户输入，以#号结束，输出按字典次序最小的字符

运行结果如下

 

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53

import javax.swing.JTextPane; import javax.swing.JTextField; import javax.swing.JPanel; import javax.swing.JFrame; import javax.swing.JScrollPane; import java.awt.BorderLayout; import java.awt.event.ActionListener; import java.awt.event.KeyAdapter; import java.awt.event.KeyEvent; import java.awt.event.ActionEvent; /***************************** 作者：Jerome Chan 网站: www.jeromechan.com *****************************/ public class KeyDemo {     private static char minChar = 'a';     private static void createAndShowGUI() {     final JTextField textfield = new JTextField(20);     final JTextPane panel = new JTextPane();     panel.setEditable(false);     textfield.addKeyListener(new KeyAdapter() {         public void keyReleased(KeyEvent e) {         if (e.getKeyChar() == '#') {             panel.setText("你输入最小的字符是:" + minChar);             textfield.setText("");         }         else {         if(e.getKeyChar() < minChar) {             minChar=e.getKeyChar();             //panel.setText("");         }         //else         //panel.setText("");         }     }});     JFrame.setDefaultLookAndFeelDecorated(true);         //Create and set up the window.         JFrame frame = new JFrame("HelloWorldSwing");         frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);     frame.getContentPane().add(textfield, BorderLayout.NORTH);     frame.getContentPane().add(new JScrollPane(panel), BorderLayout.CENTER);     frame.setSize(300, 400);     frame.pack();     frame.setVisible(true);     }     public static void main(String[] args) {     javax.swing.SwingUtilities.invokeLater(new Runnable() {         public void run() {             createAndShowGUI();         }     });     } }