Shisoku.java

Shisoku.java

   1 /*
   2  * Shisoku.java --- 四則演算プログラム (GUI 版)
   3  */
   4 
   5 import java.awt.*;       // Frame
   6 import java.awt.event.*; // WindowAdapter 等
   7 
   8 public class Shisoku extends Frame implements ActionListener {
   9   TextField tf_a, tf_b, wa, sa, seki, syou;
  10   Button bt, bt2;
  11 
  12   Shisoku() {
  13     setSize(400, 400);
  14     addWindowListener(new WindowAdapter() {
  15       public void windowClosing(WindowEvent e) {
  16         System.exit(0);
  17       }
  18     });
  19 
  20     setLayout(new GridLayout(7,2));
  21     add(new Label("a"));
  22     tf_a = new TextField("0", 10);
  23     add(tf_a);
  24     add(new Label("b"));
  25     tf_b = new TextField("0", 10);
  26     add(tf_b);
  27     add(new Label("a+b="));
  28     wa = new TextField("0", 10); add(wa);
  29     add(new Label("a-b="));
  30     sa = new TextField("0", 10); add(sa);
  31     add(new Label("a*b="));
  32     seki = new TextField("0", 10); add(seki);
  33     add(new Label("a/b="));
  34     syou = new TextField("0", 10); add(syou);
  35     bt = new Button("start");
  36     add(bt);
  37     bt.addActionListener(this); 
  38     bt2 = new Button("exit");
  39     add(bt2);
  40     bt2.addActionListener(this); 
  41   }
  42 
  43   public void actionPerformed(ActionEvent e) {
  44     if (e.getSource() == bt) {
  45       double a = Double.valueOf(tf_a.getText().trim()).doubleValue();
  46       double b = Double.valueOf(tf_b.getText().trim()).doubleValue();
  47       wa.setText("" + (a + b));
  48       sa.setText("" + (a - b));
  49       seki.setText("" + (a * b));
  50       syou.setText("" + (a / b));
  51     }
  52     else if (e.getSource() == bt2) {
  53       System.exit(0);
  54     }
  55   }
  56 
  57   public static void main(String args[]) {
  58     Frame f = new Shisoku();
  59     f.show();
  60   }
  61 }