package HelloJava;  import java.awt.BorderLayout;  import java.awt.Container;  import java.awt.GridLayout;  import java.awt.event.*;  import java.security.cert.CollectionCertStoreParameters;    import javax.swing.*;  import javax.swing.text.Document;  import java.util.*;    public class Myb extends JFrame implements ActionListener {       JLabel interestLabel = new JLabel("姓名");        JTextField text = new  JTextField();          JLabel interestLabe2 = new JLabel("成绩");        JTextField text1 = new  JTextField();       JButton button = new JButton ("确认");      JTextArea textArea = new JTextArea(5,25);        List
     
       list = new ArrayList
      
       ();       Myb()       {            super("work");            Container contentPane = getContentPane();                   JPanel northPanel = new JPanel();            northPanel.setLayout(new GridLayout(2,1));              Box box1 = Box.createHorizontalBox();            Box box2 = Box.createHorizontalBox();                      box1.add(Box.createHorizontalStrut(3));            box1.add(interestLabel );            text.setColumns(5);              box1.add(text );            box1.add(interestLabe2 );            box1.add(text1);            button.addActionListener(new ActionListener() {                         @Override              public void actionPerformed(ActionEvent e) {                                    // TODO 自动生成的方法存根                  textArea.setText("");                  list.add(new paixun(text.getText().toString(),Double.parseDouble(text1.getText().toString())));                   Collections.sort(list);                  for(paixun p:list)                    textArea.setText(textArea.getText()+"\n"+p.name +"\t"+p.Grade+ "分");                                      text.setText("");                  text1.setText("");              }          });             box1.add(button);                    northPanel.add(box1);                    contentPane.add(northPanel, BorderLayout.NORTH);                       JScrollPane scrollPane = new JScrollPane(textArea);            contentPane.add(scrollPane, BorderLayout.CENTER);            setVisible(true);            setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);            setSize(400, 300);       }        public void actionPerformed(ActionEvent e)                     {                  return;             }       class paixun implements Comparable
       
        {           public String name;           public Double Grade;           paixun(String name,Double Grade){               this.name=name;               this.Grade=Grade;           }          @Override          public int compareTo(paixun o) {              // TODO 自动生成的方法存根              return Grade.compareTo(o.Grade);          }            }       public static void main(String args[])       {            new Myb();       }  }