Java 计算器

package graphics;
// debuged already ok
import java.util.Date;
import java.awt.*;
import java.awt.event.*;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
//++
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
//++
import javax.swing.*;
//import javax.swing.event.CaretEvent;
//import javax.swing.event.CaretListener;

public class CalculatorX extends JFrame implements ActionListener
{
    /**
     *
     */
    public File file; //++
    private static final long serialVersionUID = 1L;
    private JButton but[],enter;
    public enum MyOperator{ADD, SUB, MUL, DIV}
    private MyOperator oper;
    private JTextField text_area;
    private double result, last;
    private HelpDialog viewdialog, helpdialog;
    private ClearDialog historydialog;
    ///private String historytext;
    private int flag, operatorflag, numberflag, enterflag;
    public CalculatorX() throws IOException
    {
        super("CalculatorX");
        this.setResizable(false);
        this.setAlwaysOnTop(true);
        this.setBounds(300, 245, 240, 340);
        this.setDefaultCloseOperation(3);

        this.file = new File("cacu_history");
        if(this.file.length() != 0)
            this.writeToFile("/n----------------------" + //怎么才能放在析构函数里
                             "--------------------/n/n");

        text_area = new JTextField("0");
        text_area.setEditable(false);


        Dimension mini_size  = new Dimension(1000,40);
        text_area.setPreferredSize(mini_size);
        System.out.println("tr"+text_area.getSize().width+"tr"+text_area.getHeight());

        text_area.setFont(new Font("Consolas", 0, 25));//"Default", Font.bold, 20
        text_area.setHorizontalAlignment(JTextField.RIGHT);
        this.getContentPane().add(text_area, BorderLayout.NORTH);



        JPanel jpanel = new JPanel();
        jpanel.setLayout(new FlowLayout(FlowLayout.CENTER,0,0));
        this.getContentPane().add(jpanel);             //

        JPanel jpanel_max = new JPanel();
        Dimension jpmax_size  = new Dimension(225,141);
        jpanel_max.setPreferredSize(jpmax_size);
        jpanel_max.setLayout(new FlowLayout(FlowLayout.RIGHT,5,7));
        jpanel.add(jpanel_max);


        JPanel jpanel_min = new JPanel();
        Dimension jpmin_size  = new Dimension(170,100);
        jpanel_min.setPreferredSize(jpmin_size);
        jpanel_min.setLayout(new FlowLayout(FlowLayout.RIGHT,5,7));
        jpanel.add(jpanel_min);

        JPanel jpanel_enter = new JPanel(new FlowLayout(FlowLayout.RIGHT,5,7));
        Dimension enter_panel_size  = new Dimension(55,100);
        jpanel_enter.setPreferredSize(enter_panel_size);
        jpanel.add(jpanel_enter);

        String b[] = {"√", "±", "C", "+", "7", "8", "9", "-", "4", "5", "6",
                   //  0     1     2    3    4    5    6    7    8    9    10
                "*", "1", "2", "3", "0", ".", "/"};
               //11   12  13   14    15   16   17
        but = new JButton[b.length];

        for(int i = 0; i<12; i++)
        {
            but[i] = new JButton(b[i]);
            Dimension same_size  = new Dimension(50,40);
            but[i].setPreferredSize(same_size);
            if(i > 0)
                but[i].setFont(new Font("Default", 0, 16));
            but[i].addActionListener(this);
            jpanel_max.add(but[i]);
        }

        for(int i = 12; i<18; i++)
        {
            but[i] = new JButton(b[i]);
            Dimension same_size  = new Dimension(50,40);
            but[i].setPreferredSize(same_size);
            but[i].setFont(new Font("Default", 0, 16));
            but[i].addActionListener(this);
            jpanel_min.add(but[i]);
        }

        enter = new JButton("=");
        enter.setFont(new Font("Consolas", 0, 25));
        Dimension same_size = new Dimension(50,86);
        enter.setPreferredSize(same_size);
        enter.addActionListener(this);
        jpanel_enter.add(enter);

        addmiiMenu();

        this.setVisible(true);

        helpdialog = new HelpDialog(this, "关于产品", 320, 150);
        viewdialog = new HelpDialog(this, "使用说明", 420, 350);
        historydialog = new ClearDialog(this, "计算记录", 620, 400);
    }
    public void finalize() throws IOException//没有用     待解决
    {
        System.out.print("  finalize() throws IOException ");//NOY
        this.writeToFile("---------------------------" +
                "/n");
    }
    public void addmiiMenu()
    {
        JMenuBar menubar = new JMenuBar();
        this.setJMenuBar(menubar);

        String menustr[] = {"查看", "文件", "帮助(F1)"};
        JMenu menu[] = new JMenu[menustr.length];
        for(int i = 0; i<menustr.length; i++)
        {
            menu[i] = new JMenu(menustr[i]);
            menubar.add(menu[i]);
        }
        JMenuItem menu_view_history = new JMenuItem("查看计算记录");
        menu_view_history.addActionListener(this);
        menu[0].add(menu_view_history);

        JMenuItem menu_help_view = new JMenuItem("查看帮助  ");
        menu_help_view.addActionListener(this);

        menu_help_view.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_F1, InputEvent.CTRL_MASK));
        JMenuItem menu_help_about = new JMenuItem("关于计算器");
        menu_help_about.addActionListener(this);
        menu[2].add(menu_help_view);
        menu[2].addSeparator();
        menu[2].add(menu_help_about);
        menu[2].setMnemonic(KeyEvent.VK_F1);

    }
    public static void main(String args[]) throws IOException
    {
        new CalculatorX();
    }
    private class ClearDialog extends JDialog implements ActionListener
    {
        /**
         *
         */
        private static final long serialVersionUID = 1L;
        JFrame jframe;
        JPanel jpanel;
        JTextArea jtexr;
        public JButton clear;
        ClearDialog(JFrame jframe, String st, int wid, int hig)
        {
            super(jframe, st, true);
            this.jframe=jframe;                //
            this.setSize(wid,hig);
            jpanel = new JPanel();
            clear = new JButton("删除记录");
            clear.addActionListener(this);
            clear.addActionListener((ActionListener) jframe);
            //this.getContentPane().setLayout(new FlowLayout());
            this.getContentPane().add(jpanel, "North");
            jpanel.setLayout(new FlowLayout(FlowLayout.LEFT));
            jpanel.add(clear);

            jtexr = new JTextArea("");
            jtexr.setEditable(true);
            jtexr.setFont(new Font("仿宋", 1, 15));
            jtexr.setLineWrap(true);                        //自动换行

            this.getContentPane().add(new JScrollPane(jtexr));
            this.setDefaultCloseOperation(HIDE_ON_CLOSE);
        }
        void show (String message)
        {
            jtexr.setText(message);
            this.setLocation(jframe.getX()+100,jframe.getY()+100);
            this.setVisible(true);
        }
        @Override
        public void actionPerformed(ActionEvent e) {
            // TODO Auto-generated method stub
            if(e.getSource()instanceof JButton)
            {
                jtexr.setText("");
            }
        }
    }
    private class HelpDialog extends JDialog
    {
        /**
         *
         */
        private static final long serialVersionUID = 1L;
        JFrame jframe;
        JTextArea jtexr;
        HelpDialog(JFrame jframe, String st, int wid, int hig)
        {
            super(jframe, st, true);
            this.jframe=jframe;                //
            this.setSize(wid,hig);

            jtexr = new JTextArea("");
            jtexr.setEditable(false);
            jtexr.setFont(new Font("仿宋", 1, 15));
            jtexr.setLineWrap(true);                        //自动换行
            //jtexr.setEnabled(false);
            this.getContentPane().add(new JScrollPane(jtexr));
            this.setDefaultCloseOperation(HIDE_ON_CLOSE);
        }
        void show (String message)
        {
            jtexr.setText(message);
            this.setLocation(jframe.getX()+100,jframe.getY()+100);
            this.setVisible(true);
        }
    }
    @Override

    public void actionPerformed(ActionEvent e)
    {
        // TODO Auto-generated method stub
        if(e.getSource() == historydialog.clear)
        {
            this.file.delete();
            this.file = new File("cacu_history");
        }



        DecimalFormat df = new DecimalFormat("#############.#############");
        if(e.getSource()instanceof JMenuItem)                    //MenuItem
        {
            if(e.getActionCommand()==("查看计算记录"))
                try {
                    if(this.file.length()!=0)
                        historydialog.show(this.readFromFile());
                    else
                        historydialog.show("无记录");
                } catch (IOException e1) {
                    // TODO Auto-generated catch block
                    e1.printStackTrace();
                }


            if(e.getActionCommand()=="查看帮助  ")
                viewdialog.show("实验中" +
                        "已经将确认键立起" +
                        "/n/n" +
                        "解决了小数点移位，使之趋于精确" +
                        "/n/n" +
                        "解决了无优先级连徐运算  最大长度仍可输入并运算" +
                        "/n/n" +
                        "可以使用计算器进行如加、减、乘、除这样简单的运算。" +
                        "/n/n" +
                        "单击“查看”菜单，然后单击所需模式。" +
                        "/n/n" +
                        "切换模式时，将清除当前的计算。但会保留“记忆钥匙”所存储的计算历史记录和数字。" +
                        "/n/n" +
                        "单击计算器键进行所需的计算");
            if(e.getActionCommand()=="关于计算器")
                helpdialog.show("/n/n    All rights reserved by " +
                        "/n       Mr Baoning Gai" +
                        "/n         11/16/2010");
        }
        if(e.getSource()instanceof JButton)
        {
            if( text_area.getText().equals("Overflow")||text_area.getText().equals("Error : Infinity")||text_area.getText().equals("Error :NaN") )
                Clear();
            if( (text_area.getText().length()-flag)<15||operatorflag==1 )
            {
                if(e.getSource()==but[4])
                {
                    Addnumber(7);
                }
                if(e.getSource()==but[5])
                {
                    Addnumber(8);
                }
                if(e.getSource()==but[6])
                {
                    Addnumber(9);
                }
                if(e.getSource()==but[8])
                {
                    Addnumber(4);
                }
                if(e.getSource()==but[9])
                {
                    Addnumber(5);
                }
                if(e.getSource()==but[10])
                {
                    Addnumber(6);
                }
                if(e.getSource()==but[12])
                {
                    Addnumber(1);
                }
                if(e.getSource()==but[13])
                {
                    Addnumber(2);
                }
                if(e.getSource()==but[14])
                {
                    Addnumber(3);
                }
                if(e.getSource()==but[15])
                {
                    Addnumber(0);
                }
            }


                if(e.getSource()==but[16])                     //not complement
                {
                    try
                    {
                        Integer.parseInt(text_area.getText());
                        flag = 1;
                    }
                    catch(NumberFormatException nfe)
                    {
                        System.out.println("!");
                    }
                    finally{}
                 }
                if(e.getSource()==but[3])                     //not complement
                {

                    if(numberflag == 1&&oper != null)
                        try {
                            Operate();
                        } catch (IOException e1) {
                            // TODO Auto-generated catch block
                            e1.printStackTrace();
                        }
                    result = Double.parseDouble( text_area.getText() );
                    oper = MyOperator.ADD;
                    operatorflag = 1;
                    numberflag = 0;
                    enterflag = 0;//
                }
                if(e.getSource()==but[7])                     //not complement
                {
                    if(numberflag == 1&&oper != null)
                        try {
                            Operate();
                        } catch (IOException e1) {
                            // TODO Auto-generated catch block
                            e1.printStackTrace();
                        }
                    result = Double.parseDouble( text_area.getText() );
                    oper = MyOperator.SUB;
                    operatorflag = 1;
                    numberflag = 0;
                    enterflag = 0;//
                }
                if(e.getSource()==but[11])                     //not complement
                {
                    if(numberflag == 1&&oper != null)
                        try {
                            Operate();
                        } catch (IOException e1) {
                            // TODO Auto-generated catch block
                            e1.printStackTrace();
                        }
                    result = Double.parseDouble( text_area.getText() );
                    oper = MyOperator.MUL;
                    operatorflag = 1;
                    numberflag = 0;
                    enterflag = 0;//
                }
                if(e.getSource()==but[17])                     //not complement
                {
                    if(numberflag == 1&&oper != null)
                        try {
                            Operate();
                        } catch (IOException e1) {
                            // TODO Auto-generated catch block
                            e1.printStackTrace();
                        }
                    result = Double.parseDouble( text_area.getText() );
                    oper = MyOperator.DIV;
                    operatorflag = 1;
                    numberflag = 0;
                    enterflag = 0;//  = 之后可以用当前数做前值
                }
                if(e.getSource()==but[0])                     //求根
                {
                    double a = Double.parseDouble( text_area.getText() );
                    if(a<=0)
                    {
                        text_area.setText("Error :NaN");
                        return;
                    }
                    a = Math.sqrt(a);
                    String str = "" + df.format(a);
                    try {
                        this.writeToFile("sqrt(" + text_area.getText() + ") =" + a + Addtime() + "/n");
                        }
                    catch (IOException e1) {}
                    text_area.setText(str);
                    result = Double.parseDouble( text_area.getText() );
                    operatorflag = 1;

                }
                if(e.getSource()==but[1])                     //not complement
                {
                    double a = Double.parseDouble( text_area.getText() );
                    a = 0 - a;
                    String str = "" + df.format(a);
                    text_area.setText(str);
                    result = Double.parseDouble( text_area.getText() );
                }
                if(e.getSource()==but[2])                     //not complement
                {
                Clear();
                }
                if(e.getSource()==enter&&oper!=null)                     // complement
                    {
                    try {
                        Operate();
                    } catch (IOException e1) {
                        // TODO Auto-generated catch block
                        e1.printStackTrace();
                    }
                    operatorflag = 1;      //仅仅是为了变 0
                    enterflag = 1;
                }
            System.out.print(" result="+result);//NOY
            System.out.print(" last="+last);//NOY
            System.out.print(" flag="+flag);//NOY
            System.out.print(" operatorflag="+operatorflag);//NOYoperatorflag
            System.out.print(" numberflag="+numberflag);
            System.out.print(oper);         //NOY
            System.out.println("!!!!!!!  enterflag="+enterflag);
        }
    }
    public void Clear()
    {
        text_area.setText("0");
        oper = null;
        result = 0;
        operatorflag = 0;
        numberflag = 0;
    }
    public String Pointmove(String str, int len)        //小数点移位
    {
        int point_position = str.indexOf(".")+1;   //查找小数点的位置
        int point_number = str.length() - point_position;
        int delete_number = str.length() - len;    //与小数点无关
        int need_number = point_number - delete_number;

        String str_format = "#";
        if(need_number<0||point_position>15)
            return "Overflow";
        if(need_number>0)
            str_format += ".";

        for(int i=0; i<need_number; i++)
        {
            str_format+="#";
        }
        DecimalFormat df = new DecimalFormat(str_format);
        String st = "" + df.format(Double.parseDouble(str));
        if(st.length()>15)
            return "Overflow";                //因为小数点位置在大于15 或无小数点时仍应控制长度
        return st;
    }
    public String Addtime()
    {
        SimpleDateFormat format_time = new SimpleDateFormat("HH:mm ss,MM/dd/yyyy");
        Date currenttime = new Date();
        String str_time = " time:" + format_time.format(currenttime);
        return str_time;
    }
    public void Addnumber(int getnumber)
    {
        DecimalFormat df = new DecimalFormat("#############.#############");
        String str;
        if(enterflag==1)
            oper = null;
        if(operatorflag==1)
        {
            str = "0";
            operatorflag = 0;
        }
        else
        {
            str = text_area.getText();
        }
        if(flag==1)
        {
            str += ".";
            flag = 0;
        }
            numberflag = 1;
            enterflag = 0;
            str =str+getnumber;
        double input = Double.parseDouble( str );
        str = "" + df.format(input);
        last = input;
        text_area.setText(str);
        System.out.println("click "+getnumber);
    }
    public void Operate() throws IOException
    {
        DecimalFormat df = new DecimalFormat("#############.#############");
        System.out.println("clik enter");               //NOY
          double b = last;
          double a = result;
          String add_history = "";
            switch(oper)
            {
            case ADD :
                add_history =a+"+"+b+"="+(a+b)+Addtime()+"/n";
                a = a+b;
                break;
            case SUB :
                add_history =a+"-"+b+"="+(a+b)+Addtime()+"/n";
                a = a-b;
                break;
            case MUL :
                add_history =a+"*"+b+"="+(a+b)+Addtime()+"/n";
                a = a*b;
                break;
            case DIV :
                a = a/b;
                add_history =a+"/"+b+"="+(a+b)+Addtime()+"/n";
                if(b==0)
                {
                    text_area.setText("Error : Infinity");
                    return;
                }
                break;
            }
            numberflag = 0;
            result = a;
            String str = "" + df.format(result);
            //++
            this.writeToFile(add_history);
            //++
            if(str.length()<=15)
            {
                text_area.setText(str);
            }
            else
            {
                str = Pointmove(str, 15);
                text_area.setText(str);
            }
    }
    public void writeToFile( String lines ) throws IOException//将字符串lines写入当前文本文件中
    {

            FileWriter fout = new FileWriter(this.file, true);//文件字符流对象
            fout.write(lines);                 //向文件字符流写入一个字符串
            fout.close();
    }
    public String readFromFile() throws IOException//使用流从当前文本文件中读取字符
    {
        System.out.println("read");
        char lines[] = null;
            FileReader fin = new FileReader( this.file );//创建字符输入流对象
            lines = new char[(int)this.file.length()];
            fin.read(lines);                             //读取字符流到字符数组
            fin.close();
            return new String(lines);
    }
}