java小计算器

只支持鼠标操作的。

打包好的源代码下载地址：

http://115.com/file/anc92nmj#
calculator.zip

/**
 * @(#)CaculatorFrame.java
 *
 *
 * @author huangliangming
 * @说明： 实现了基本功能，只支持鼠标操作
           
 * @version 1.00 2012/4/3
 */
package calculator;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class CaculatorFrame extends JFrame
{
    private JButton jButton;
    private JTextField textField;
    int w = 242,
        h = 260;
    int buttonSizeX = 45,
        buttonSizeY = 35;
    static Double num1=0.0;
    static String cal;
    static boolean isANext = false;
    public CaculatorFrame()
    {
        Dimension screensize = Toolkit.getDefaultToolkit().getScreenSize();
        int swidth = (int)screensize.getWidth();
        int sheight = (int)screensize.getHeight();
        setBounds(swidth/2-w/2,sheight/2-h/2,w,h);
        setResizable(false);
        setVisible(true);
        this.addWindowListener(new WindowAdapter()
        {
            public void windowClosing(WindowEvent e)
            {
                CaculatorFrame.this.windowClosed();
            }
        });
        initButton();
        repaint();
    }
    
    public void initButton()
    {
        setLayout(null);
        textField = new JTextField("0");
        add(textField);
        textField.setBounds(2,2,w-10,30);
        textField.setHorizontalAlignment(JTextField.RIGHT);
        textField.setEditable(false);
        textField.setBackground(Color.WHITE);
        //画数字键
 JPanel numPanel = new JPanel();
          numPanel.setLayout(new GridLayout(4,4,5,5));
          String str = "789+456-123x0.c/";
        for (int i=0; i<16; i++)
        {
            jButton = new JButton(str.substring(i,i+1));
            numPanel.add(jButton);
            if (i == 3 || i == 7 || i == 11 || i == 15)
            {
                jButton.addActionListener(new ActionListener()
                {
                    public void actionPerformed(ActionEvent e)
                    {
                        cal = e.getActionCommand();
                        try
                        {
                            num1 = Double.parseDouble(textField.getText());
                            if (num1 == 0.0)
                            {
                                textField.setText("");
                            }
                        }
                        catch (NumberFormatException event)
                        {
                            textField.setText("");
                        }
                        textField.setText(e.getActionCommand());
                    }
                });
            }
            else if (i == 14)
            {
                jButton.addActionListener(new DelEvent(textField));
            }
            else
            {
                jButton.addActionListener(new ActionListener()
                {
                    public void actionPerformed(ActionEvent e)
                    {
                        String text = textField.getText();
                        String s = e.getActionCommand();
                        System.out.println("text:"+text);
                        System.out.println("s:"+s);
                        if (isANext == true)
                        {
                            text = "";
                            isANext = false;
                        }
                        try
                        {
                            double tmp = Double.parseDouble(text);
                            System.out.println("tmp"+tmp);
                            if (tmp == 0.0)
                            {
                                text = "";
                            }
                        }
                        catch (NumberFormatException event)
                        {
                            text = "";
                        }
                        if (s.equals("."))
                        {
                            if (text.indexOf('.')>=0)
                            {
                                return;
                            }
                            else
                            {
                                textField.setText(text+s);
                                return;
                            }
                        }
                        textField.setText(text+s);
                    }
                });
            }
        }
        add(numPanel);
        numPanel.setBounds(2,40,2+(buttonSizeX*4),50+buttonSizeY*4);
        
        JButton jButtonR = new JButton("=");
        add(jButtonR);
        jButtonR.setBounds(7+(buttonSizeX*4),80+buttonSizeY*3,buttonSizeX, 5+buttonSizeY);
        jButtonR.addActionListener(new ActionListener()
        {
            public void actionPerformed(ActionEvent e)
            {
                String result;
                double num2=0;
                JButton jB = (JButton)e.getSource();
                try
                {
                    num2 = Double.parseDouble(textField.getText());
                }
                catch (NumberFormatException event)
                {
                    textField.setText("");
                    System.out.println("num2输入错误");
                }
                System.out.println(cal);
                if (cal.equals("+"))
                {
                    result = String.valueOf(num1 + num2);
                }
                else if (cal.equals("-"))
                {
                    result = String.valueOf(num1 - num2);
                }
                else if (cal.equals("x"))
                {
                    result = String.valueOf(num1 * num2);
                }
                else if (cal.equals("/"))
                {
                    result = String.valueOf(num1 / num2);
                }
                else
                {
                    result = "";
                    System.out.println("计算出错");
                }
                textField.setText(result);
                isANext = true;
            }
        });
        validate();
    }
    
    protected void windowClosed()
    {
        // Exit application.
 System.out.println("exited!");
        System.exit(0);
    }
}

class DelEvent implements ActionListener
{
    private JTextField tField;
    DelEvent(JTextField textField)
    {
        tField = textField;
    }
    public void actionPerformed(ActionEvent e)
    {
        tField.setText("0");
    }
}

/**
 * @(#)Caculator.java
 *
 * Caculator application
 *
 * @author huangliangming
 * @version 1.00 2012/4/3
 */
 package calculator;

public class Caculator
{
    public static void main(String[] args)
    {
        CaculatorFrame caculatorFrame = new CaculatorFrame();
        // TODO, add your application code
 System.out.println("Hello World!");
    }
}