package untitled2;import java.awt.*;import java.awt.event.*;import java.applet.*;import javax.swing.*;import com.borland.jbcl.layout.*;public class qchange extends Applet {  double c[] = {1609.3,0.3048,0.0254};  double d[] = {1000,1,0.001};  double mid;  double start;  double end;  int n = 0;  int m = 0;  boolean isStandalone = false;  JRadioButton jRadioButton1 = new JRadioButton();  JRadioButton jRadioButton2 = new JRadioButton();  JRadioButton jRadioButton3 = new JRadioButton();  JRadioButton jRadioButton4 = new JRadioButton();  JRadioButton jRadioButton5 = new JRadioButton();  JRadioButton jRadioButton6 = new JRadioButton();  ButtonGroup buttonGroup1 = new ButtonGroup();  ButtonGroup buttonGroup2 = new ButtonGroup();  JTextField text1 = new JTextField();  JTextField text2 = new JTextField();  JButton jButton1 = new JButton();  JButton jButton2 = new JButton();  XYLayout xYLayout1 = new XYLayout();  Label label1 = new Label();  Label label2 = new Label();  /**Get a parameter value*/  public String getParameter(String key, String def) {    return isStandalone ? System.getProperty(key, def) :      (getParameter(key) != null ? getParameter(key) : def);  }  /**Construct the applet*/  public qchange() {  }  /**Initialize the applet*/  public void init() {    try {      jbInit();    }    catch(Exception e) {      e.printStackTrace();    }  }  /**Component initialization*/  private void jbInit() throws Exception {    jRadioButton1.setFont(new java.awt.Font("Dialog", 0, 16));    jRadioButton1.setText("英里");    jRadioButton1.addItemListener(new java.awt.event.ItemListener() {      public void itemStateChanged(ItemEvent e) {        jRadioButton1_itemStateChanged(e);      }    });    this.setLayout(xYLayout1);    jRadioButton2.setFont(new java.awt.Font("Dialog", 0, 16));    jRadioButton2.setText("英尺");    jRadioButton2.addActionListener(new java.awt.event.ActionListener() {      public void actionPerformed(ActionEvent e) {        jRadioButton2_actionPerformed(e);      }    });    jRadioButton2.addItemListener(new java.awt.event.ItemListener() {      public void itemStateChanged(ItemEvent e) {        jRadioButton1_itemStateChanged(e);      }    });    jRadioButton2.addHierarchyBoundsListener(new java.awt.event.HierarchyBoundsAdapter() {    });    jRadioButton3.setFont(new java.awt.Font("Dialog", 0, 16));    jRadioButton3.setText("英寸");    jRadioButton3.addItemListener(new java.awt.event.ItemListener() {      public void itemStateChanged(ItemEvent e) {        jRadioButton1_itemStateChanged(e);      }    });    jRadioButton4.setFont(new java.awt.Font("Dialog", 0, 16));    jRadioButton4.setText("公里");    jRadioButton4.addItemListener(new java.awt.event.ItemListener() {      public void itemStateChanged(ItemEvent e) {        jRadioButton2_itemStateChanged(e);      }    });    jRadioButton5.setFont(new java.awt.Font("Dialog", 0, 16));    jRadioButton5.setText("公尺");    jRadioButton5.addItemListener(new java.awt.event.ItemListener() {      public void itemStateChanged(ItemEvent e) {        jRadioButton2_itemStateChanged(e);      }    });    jRadioButton6.setFont(new java.awt.Font("Dialog", 0, 16));    jRadioButton6.setText("公分");    jButton1.setText("-->");    jButton1.addActionListener(new java.awt.event.ActionListener() {      public void actionPerformed(ActionEvent e) {        jButton1_actionPerformed(e);      }    });    jButton2.setText("-->");    jButton2.addActionListener(new java.awt.event.ActionListener() {      public void actionPerformed(ActionEvent e) {        jButton2_actionPerformed(e);      }    });    text1.setText("0");    text2.setText("0");    label1.setText("英");    label2.setText("公");    this.add(jRadioButton1,  new XYConstraints(40, 24, -1, -1));    this.add(jRadioButton2,  new XYConstraints(40, 56, -1, -1));    this.add(jRadioButton3,  new XYConstraints(40, 88, -1, -1));    this.add(jRadioButton5,  new XYConstraints(214, 56, -1, -1));    this.add(jRadioButton4,  new XYConstraints(214, 24, -1, -1));    this.add(jRadioButton6,  new XYConstraints(214, 88, -1, -1));    buttonGroup1.add(jRadioButton1);    buttonGroup1.add(jRadioButton2);    buttonGroup1.add(jRadioButton3);    buttonGroup2.add(jRadioButton4);    buttonGroup2.add(jRadioButton5);    buttonGroup2.add(jRadioButton6);    this.add(text1,   new XYConstraints(40, 126, 176, 24));    this.add(jButton1, new XYConstraints(219, 127, 58, 21));    this.add(text2,  new XYConstraints(39, 165, 178, 25));    this.add(jButton2, new XYConstraints(220, 167, 58, 21));    this.add(label1,  new XYConstraints(8, 124, 27, 23));    this.add(label2,  new XYConstraints(7, 165, 28, 25));  }  /**Get Applet information*/  public String getAppletInfo() {    return "Applet Information";  }  /**Get parameter info*/  public String[][] getParameterInfo() {    return null;  }  void jRadioButton1_itemStateChanged(ItemEvent e) {      if (jRadioButton1.isSelected())         n = 1;      if (jRadioButton2.isSelected())         n = 2;      if (jRadioButton3.isSelected())         n = 3;  }  void jRadioButton2_itemStateChanged(ItemEvent e) {      if (jRadioButton4.isSelected())         m = 1;      if (jRadioButton5.isSelected())         m = 2;      if (jRadioButton6.isSelected())         m = 3;  }  void jButton1_actionPerformed(ActionEvent e) {      String str = text1.getText();      if (str!=null){        try{           start = Double.parseDouble(str);           switch (n){               case 1:                  mid = start * c[0];                  break;               case 2:                  mid = start * c[1];                  break;               case 3:                  mid = start * c[2];                  break;           }           switch (m){                  case 1:                  end = mid / d[0];                  break;               case 2:                  end = mid / d[1];                  break;               case 3:                  end = mid / d[2];                  break;            }            text2.setText(String.valueOf(end));            }            catch(Exception ex){}     }  }void jButton2_actionPerformed(ActionEvent e) {      String str = text2.getText();      if (str!=null){        try{           start = Double.parseDouble(str);           switch (m){               case 1:                  mid = start * d[0];                  break;               case 2:                  mid = start * d[1];                  break;               case 3:                  mid = start * d[2];                  break;           }           switch (n){                  case 1:                  end = mid / c[0];                  break;               case 2:                  end = mid / c[1];                  break;               case 3:                  end = mid / c[2];                  break;            }            text1.setText(String.valueOf(end));            }            catch(Exception ex){}     }  }  void jRadioButton2_actionPerformed(ActionEvent e) {  }}