java简单计算器，只能鼠标点击数字

包含三个类

1.主类，包括计算器界面和每个键的功能实现calculator.java

package com.bj.jsq;

import java.awt.EventQueue;
import javax.swing.JFrame;
import javax.swing.JPanel;
import java.awt.Dimension;
import java.awt.TextField;
import java.awt.Label;
import java.awt.Button;
import java.awt.Toolkit;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import java.awt.Color;
import java.awt.SystemColor;
import javax.swing.JMenuBar;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;

public class calculator extends JFrame {
    private static final long serialVersionUID = 1L;
    private JPanel contentPane;
    public static double n; 
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    calculator frame = new calculator(); 
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the frame.
     */
    public calculator() {
        setResizable(false);
        setBackground(SystemColor.inactiveCaptionBorder);  //
        setTitle("u7B80u5355u8BA1u7B97u5668");
        Dimension screen=Toolkit.getDefaultToolkit().getScreenSize();
        int x=(int)screen.getWidth();
        int y=(int)screen.getHeight();
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds((x-293)/2, (y-333)/2, 293, 315);
        contentPane = new JPanel();
        setContentPane(contentPane);
        contentPane.setLayout(null);
        final TextField txtInput = new TextField();
        
        txtInput.setBounds(62, 10, 205, 23);
        contentPane.add(txtInput);
        final TextField txtOutput = new TextField();
        txtOutput.setEditable(false);
        txtOutput.setBounds(62, 49, 205, 23);
        contentPane.add(txtOutput);
        
        Label label = new Label("input");                 //
        //label.setBackground(UIManager.getColor("window"));
        label.setForeground(new Color(153, 50, 204));
        label.setBounds(15, 10, 41, 23);
        contentPane.add(label);
        
        Label label_1 = new Label("result");             //
        label_1.setForeground(new Color(153, 50, 204));
        label_1.setBounds(15, 49, 41, 23);
        contentPane.add(label_1);
        
        Button btn7 = new Button("7");                  //
        btn7.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+"7");
            }
        });
        btn7.setBounds(20, 92, 49, 23);
        contentPane.add(btn7);
        
        Button btn8 = new Button("8");                  ////
        btn8.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+"8");
            }
        });
        btn8.setBounds(79, 92, 49, 23);
        contentPane.add(btn8);
        
        Button button_2 = new Button("+");
        button_2.setForeground(new Color(153, 50, 204));
        button_2.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+" + ");
                
                
            }
        });
        button_2.setBounds(218, 92, 49, 23);
        contentPane.add(button_2);
        
        Button btn9 = new Button("9");
        btn9.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+"9");
            }
        });
        btn9.setBounds(147, 92, 49, 23);
        contentPane.add(btn9);
        
        Button btn5 = new Button("5");
        btn5.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+"5");
            }
        });
        btn5.setBounds(79, 136, 49, 23);
        contentPane.add(btn5);
        
        Button btn4 = new Button("4");
        btn4.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+"4");
            }
        });
        btn4.setBounds(20, 136, 49, 23);
        contentPane.add(btn4);
        
        Button button_6 = new Button("-");
        button_6.setForeground(new Color(153, 50, 204));
        button_6.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+" - ");                
            }
        });
        button_6.setBounds(218, 136, 49, 23);
        contentPane.add(button_6);
        
        Button btn6 = new Button("6");
        btn6.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+"6");
            }
        });
        btn6.setBounds(147, 136, 49, 23);
        contentPane.add(btn6);
        
        Button btn2 = new Button("2");
        btn2.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+"2");
            }
        });
        btn2.setBounds(79, 183, 49, 23);
        contentPane.add(btn2);
        
        Button btn1 = new Button("1");
        btn1.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+"1");
            }
        });
        btn1.setBounds(20, 183, 49, 23);
        contentPane.add(btn1);
        
        Button button_10 = new Button("cls");
        button_10.setForeground(new Color(153, 50, 204));
        button_10.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText("");
                txtOutput.setText("");
            }
        });
        button_10.setBounds(218, 183, 49, 23);
        contentPane.add(button_10);
        
        Button btn3 = new Button("3");
        btn3.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+"3");
            }
        });
        btn3.setBounds(147, 183, 49, 23);
        contentPane.add(btn3);
        
        Button btndel = new Button(".");
        btndel.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+".");
            }
        });
        btndel.setBounds(79, 230, 49, 23);
        contentPane.add(btndel);
        
        Button btn0 = new Button("0");
        btn0.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                txtInput.setText(txtInput.getText()+"0");
            }
        });
        btn0.setBounds(20, 230, 49, 23);
        contentPane.add(btn0);
    
        Button btne = new Button("=");  //
        btne.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                String str=txtInput.getText();
                String[]ss;
                String regex1="( \p{Punct} )\1++";//有若干个标点符号重叠的正则式
                String regex2="( \p{Punct} )$";//标点符号在行末的正则表达式
                str=str.replaceAll(regex1, "$1");
                str=str.replaceAll(regex2, "");
                int i;
                ss=str.split(" ");
                try{
                n=Double.parseDouble(ss[0]);
                for(i=0;i<ss.length;i++)
                {
                    if(ss[i].equals("+"))
                    {
                        n=n+Double.parseDouble(ss[i+1]);
                    }
                    if(ss[i].equals("-"))
                    {
                        n=n-Double.parseDouble(ss[i+1]);
                    }
                }
                txtOutput.setText(String.valueOf(n));
                }catch(Exception ex){
                    JOptionPane.showMessageDialog(null, "请检查 输入数的格式！！重新输入");
                }
            }
        });
        btne.setForeground(new Color(153, 50, 204));
        btne.setBounds(147, 230, 49, 23);
        contentPane.add(btne);
        
        Button btnSqrt = new Button("sqrt");
        btnSqrt.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                String sqrtValue;
                if(txtInput.getText().contains("+")||txtInput.getText().contains("+"))
                    sqrtValue=txtOutput.getText();
                else
                    sqrtValue=txtInput.getText();
                try{
                txtOutput.setText(String.valueOf(Math.sqrt(Double.parseDouble(sqrtValue))));
                }catch(Exception ex){
                    JOptionPane.showMessageDialog(null, "该数不能开方，请检查数据是否错误！");
                }
                }
        });
        btnSqrt.setForeground(new Color(148, 0, 211));
        btnSqrt.setBounds(218, 230, 49, 23);
        contentPane.add(btnSqrt);
        
        JMenuBar menuBar = new JMenuBar();
        menuBar.setBounds(0,267,281, 21);
        contentPane.add(menuBar);
        
        JMenu mnNewMenu = new JMenu("帮助");//u67E5u770B
        menuBar.add(mnNewMenu);
        
        JMenuItem mntmh = new JMenuItem("帮助");//u5E2Eu52A9
        mntmh.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                calHelp ch=new calHelp();
                //ch.show(false);
                ch.setVisible(true);
            }
        });
        mnNewMenu.add(mntmh);
        
        JMenuItem mntmNewMenuItem = new JMenuItem("关于计算器");
        mntmNewMenuItem.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                calAbout ca=new calAbout();
                ca.setVisible(true);
            }
        });
        mnNewMenu.add(mntmNewMenuItem);
        setVisible(true);
    }
}

2.帮助类，只是一个窗体，显示一些帮助内容calHelp.java

package com.bj.jsq;

import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.JScrollPane;

public class calHelp extends JFrame {

    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    calHelp frame = new calHelp();
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the frame.
     */
    public calHelp() {
        setResizable(false);
        setTitle("u5E2Eu52A9");
        setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
        setBounds(100, 100, 293, 372);
        getContentPane().setLayout(null);
        
        JTextArea textArea = new JTextArea();
        textArea.setEditable(false);
        textArea.setText("1.u529Fu80FDu4ECBu7ECD
      (1)u6570u5B57u7684u52A0u51CFuFF1Bu65E0u4E58u9664u529Fu80FD
      (2)u6570u5B57u5F00u65B9uFF0Cu4E0Du8FC7u6C42u5F00u65B9u7684u65F6u5019u8F93u5165u680Fu6700u597Du4E0Du8981u5B58u5728u52A0u51CFu7B26u53F7uFF0Cu5426u5219u4F1Au63D0u793Au4F60u6570u5B57u6837u5F0Fu9519u8BEF
      (3)u6E05u7A7AuFF0Cclsu952Eu53EFu4EE5u6E05u7A7Au8F93u5165u680Fu548Cu7ED3u679Cu680Fu7684u6587u5B57

2.u6CE8u610Fu4E8Bu9879
      (1)u4E0Du8981u7528u952Eu76D8u8F93u5165u9664u4E86u52A0u51CFu53F7u548Cu5C0Fu6570u70B9u3001u6570u5B57u5916u5176u4ED6u7684u5B57u7B26u6216u8005u6C49u5B57	
      (2)u5982u679Cu8F93u5165u4E86u91CDu590Du7684u7B26u53F7u6216u8005u5728u672Bu5C3Eu51FAu73B0u4E86u7B26u53F7uFF0Cu6B64u8BA1u7B97u5668u80FDu591Fu6B63u786Eu5904u7406uFF0Cu4F46u4E5Fu4E0Du8981u4E71
u8F93u5165uFF0Cu5F00u53D1u8005u4E5Fu6CA1u6709u5168u9762u5730u8003u8651
      (3)u7B2Cu4E00u4E2Au6570u5B57u4E3Au8D1Fu6570u7684u60C5u51B5u5F00u53D1u8005u6CA1u6709u60F3u5230u89E3u51B3u65B9u6848uFF0Cu6240u4EE5u8BF7u4F7Fu7528u8005u5C3Du91CFu5C06u6B63u6570u5199u5728u7B2Cu4E00u4E2Au4F4Du7F6Eu5427");
        textArea.setBounds(0, 0, 258, 373);
        textArea.setLineWrap(true);
        getContentPane().add(textArea);
        
        JScrollPane scrollPane = new JScrollPane(textArea);
        scrollPane.setBounds(0, 0, 277, 324);
        getContentPane().add(scrollPane);
    }
}

3.关于计算器

package com.bj.jsq;

import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JCheckBox;

public class calAbout extends JFrame {
    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private JPanel contentPane;

    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    calAbout frame = new calAbout();
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the frame.
     */
    public calAbout() {
        setResizable(false);
        setTitle("u5173u4E8Eu8BA1u7B97u5668");
        setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
        setBounds(100, 100, 259, 314);
        setVisible(true);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        setContentPane(contentPane);
        contentPane.setLayout(null);

        JScrollPane scrollPane = new JScrollPane();
        scrollPane.setBounds(5, 5, 233, 266);
        contentPane.add(scrollPane);

        final JTextArea txtrauthor = new JTextArea();
        txtrauthor.setEditable(false);
        txtrauthor
                .setText("u5173u4E8Eu8BA1u7B97u5668uFF1A
   @author	u5305u622C
   @version 1.0
   @since 2014
   u6B64u8BA1u7B97u5668u53EAu7528u4E8Eu4E2Au4EBAu6B23u8D4Fu53CAu5A31u4E50uFF0Cu4E0Du5F97u53C2u4E0Eu5546u4E1Au7528u9014uFF0Cu5982u9700u8F6Cu8F7DuFF0Cu8BF7u6CE8u660Eu51FAu5904uFF01u8C22u8C22");
        scrollPane.setViewportView(txtrauthor);

        final JCheckBox checkBox = new JCheckBox("u81EAu52A8u6362u884C");
        checkBox.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                if (checkBox.isSelected()) {
                    txtrauthor.setLineWrap(true);
                }
                else
                    txtrauthor.setLineWrap(true);
            }
        });
        scrollPane.setColumnHeaderView(checkBox);
    }

}