计算器完整代码(java)

1． Calculator 类

import java.applet.*;

import java.awt.*;

import java.awt.event.*;

import java.lang.*;

import java.applet.Applet;

import javax.swing.*;

import javax.swing.border.*;

public class Calculator extends JApplet implements ActionListener

{

private final String[] KEYS={"7","8","9","/","sqrt",

"4","5","6","*","%",

"1","2","3","-","1/x",

"0","+/-",".","+","="

};

private final String[] COMMAND={"Backspace","CE","C"};

private final String[] M={" ","MC","MR","MS","M+"};

private JButton keys[]=new JButton[KEYS.length];

private JButton commands[]=new JButton[COMMAND.length];

private JButton m[]=new JButton[M.length];

private JTextField display =new JTextField("0");

// public JTextField setHorizontalAlignment(int alignment);

// private JTextField display.setHorizontalAlignment(JTextField.RIGHT)=new JTextField("0");

private void setup()

{

display.setHorizontalAlignment(JTextField.RIGHT);

JPanel calckeys=new JPanel();

JPanel command=new JPanel();

JPanel calms=new JPanel();

calckeys.setLayout(new GridLayout(4,5,3,3));

command.setLayout(new GridLayout(1,3,3,3));

calms.setLayout(new GridLayout(5,1,3,3));

for(int i=0;i

{

keys[i]=new JButton(KEYS[i]);

calckeys.add(keys[i]);

keys[i].setForeground(Color.blue);

}

keys[3].setForeground(Color.red);

keys[4].setForeground(Color.red);

keys[8].setForeground(Color.red);

keys[9].setForeground(Color.red);

keys[13].setForeground(Color.red);

keys[14].setForeground(Color.red);

keys[18].setForeground(Color.red);

keys[19].setForeground(Color.red);

for(int i=0;i

{

commands[i]=new JButton(COMMAND[i]);

command.add(commands[i]);

commands[i].setForeground(Color.red);

}

for(int i=0;i

{

m[i]=new JButton(M[i]);

calms.add(m[i]);

m[i].setForeground(Color.red);

}

JPanel panel1=new JPanel();

panel1.setLayout(new BorderLayout(3,3));

panel1.add("North",command);

panel1.add("Center",calckeys);

JPanel top=new JPanel();

top.setLayout(new BorderLayout());

display.setBackground(Color.WHITE);

top.add("Center",