The method of construction--modern software engineering

Import java.awt.*;
Import Java.awt.event.ActionListener;

Import javax.swing.*;

public class F {
JFrame frame = new JFrame ("Computer");

JPanel PL = new JPanel ();

JPanel P2 = new JPanel ();

static JTextField show = new JTextField ();

static JButton B0 = new JButton ("0");

Static JButton B1 = new JButton ("1");

static JButton B2 = new JButton ("2");

Static JButton B3 = new JButton ("3");

static JButton b4 = new JButton ("4");

static JButton B5 = new JButton ("5");

Static JButton B6 = new JButton ("6");

static JButton B7 = new JButton ("7");

static JButton B8 = new JButton ("8");

static JButton B9 = new JButton ("9");

JButton Bjia = new JButton ("+");

JButton Bjian = new JButton ("-");

JButton Bcheng = new JButton ("*");

JButton Bchu = new JButton ("/");

JButton Bdian = new JButton (".");

JButton Bdeng = new JButton ("=");

JButton Bqingchu = new JButton ("clear");

public void Y () {
Pl.setlayout (New GridLayout (1, 1));
Pl.add (show);
}

public void P () {
B1.addactionlistener (New U ());
B2.addactionlistener (New U ());
B3.addactionlistener (New U ());
B4.addactionlistener (New U ());
B5.addactionlistener (New U ());
B6.addactionlistener (New U ());
B7.addactionlistener (New U ());
B8.addactionlistener (New U ());
B9.addactionlistener (New U ());
B0.addactionlistener (New U ());

Bjia.addactionlistener (New Fu ());
Bjian.addactionlistener (New Fu ());
Bcheng.addactionlistener (New Fu ());
Bchu.addactionlistener (New Fu ());

Bdeng.addactionlistener (New Deng ());
Bqingchu.addactionlistener (New Qing ());

P2.setlayout (New GridLayout (6, 3));
P2.add (B1);
P2.add (B2);
P2.add (B3);
P2.add (B4);
P2.add (B5);
P2.add (B6);
P2.add (B7);
P2.add (B8);
P2.add (B9);
P2.add (B0);
P2.add (Bjia);
P2.add (Bjian);
P2.add (Bcheng);
P2.add (Bchu);
P2.add (Bdian);
P2.add (Bqingchu);
P2.add (Bdeng);
}

public void O () {
Frame.setlayout (New BorderLayout ());
Frame.add (PL, Borderlayout.north);
Frame.add (P2, borderlayout.center);
Frame.setsize (400, 300);
Frame.setvisible (TRUE);

}

public static void Main (string[] args) {
F f = new F ();
F.y ();
F.P ();
F.O ();

}

}
////

Import java.awt.event.ActionEvent;
Import Java.awt.event.ActionListener;

public class ya implements ActionListener {
public static String str = "";

public static String a = "";

public static String B = "";

public static String k = "";

public void actionperformed (ActionEvent e) {
String w = E.getactioncommand ();//Word

if (K.equals ("")) {
A + = W;
F.show.settext (a);

} else {
B + = W;
F.show.settext (b);
}

}

}
////
Import java.awt.event.ActionEvent;
Import Java.awt.event.ActionListener;

public class Deng implements ActionListener {

public void actionperformed (ActionEvent e) {
int a = Integer.parseint (U.A);
int b = Integer.parseint (U.B);
int c = 0;
if (u.k.equals ("+")) {
c = a + B;

} else

if (U.k.equals ("-")) {
c = A-B;

} else

if (U.k.equals ("*")) {
c = A * b;

} else

if (U.k.equals ("/")) {
c = A/b;

} else {

}

String d = string.valueof (c);
F.show.settext (d);
U.A = D;
u.b = "";
U.K = "";
}
}
///

Import java.awt.event.ActionEvent;
Import Java.awt.event.ActionListener;

public class Qing implements ActionListener {

public void actionperformed (ActionEvent e) {
U.A = "";
u.b = "";
U.K = "";
F.show.settext ("");

}

}
///

Import java.awt.event.ActionEvent;
Import Java.awt.event.ActionListener;

public class Qing implements ActionListener {

public void actionperformed (ActionEvent e) {
U.A = "";
u.b = "";
U.K = "";
F.show.settext ("");

}

}
///
2
Programming is too difficult to handle. Write out a little, but not run.

The method of construction--modern software engineering