简单的计算器（java）

一个非常简单的计算器，java实现,swing写的界面，只能进行诸如+、-、*、/的简单计算，而且没有考虑优先级

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class jsq extends JFrame ...{
    //private JFrame jframe;
    private double result=0,right=0,show,saveResult=0; 
    private boolean save=false,first=true,num=true,dolt=false;   
    private char op=0;  
    private JPanel pa1,pa2,pa3;
    private JTextField text;
    private JButton button[]=new JButton[27];
    public jsq()...{
        super("计算器0.1Beta@author 卢炬 CS0410");
        Container con=getContentPane();
        button[0]=new JButton("Backspace");
        button[1]=new JButton("CE");
        button[2]=new JButton("C");
        button[3]=new JButton("MC");
        for(int i=4;i<7;i++)...{
            button[i]=new JButton(Integer.toString(i+3));
        }
        button[7]=new JButton("/");
        button[8]=new JButton("sqrt");
        button[9]=new JButton("MR");
        for(int i=10;i<13;i++)...{
            button[i]=new JButton(Integer.toString(i-6));
        }
        button[13]=new JButton("*");
        button[14]=new JButton("%");
        button[15]=new JButton("MS");
        for(int i=16;i<19;i++)...{
            button[i]=new JButton(Integer.toString(i-15));
        }
        button[19]=new JButton("-");
        button[20]=new JButton("1/x");
        button[21]=new JButton("M+");
        button[22]=new JButton("0");
        button[23]=new JButton("+/-");
        button[24]=new JButton(".");
        button[25]=new JButton("+");
        button[26]=new JButton("=");
        EventHandler handler=new EventHandler();
        text=new JTextField();
        con.add(text,BorderLayout.NORTH);
        pa1=new JPanel();
        pa1.setLayout(new FlowLayout());
        pa1.add(new JButton("    "));
        for(int i=0;i<3;i++)
            pa1.add(button[i]);
        con.add(pa1,BorderLayout.CENTER);
        pa2=new JPanel(new GridLayout(4,6));
        for(int i=3;i<27;i++)
            pa2.add(button[i]);
        con.add(pa2,BorderLayout.SOUTH);
        pack();
        setSize(360,210);
        setVisible(true);
        for(int i=0;i<27;i++) 
            button[i].addActionListener(handler);
    }
    class EventHandler extends javax.swing.JButton implements ActionListener...{
        public void actionPerformed(ActionEvent event)...{
            JButton butn=(JButton)event.getSource();
            if(butn==button[0])...{
                if(right!=0)...{
                    String s=new Double(right).toString();
                    s=s.substring(0,s.length()-1);
                    right=Double.parseDouble(s);
                    show = right;
                }
            }
            else if(butn==button[1]) ...{ right=0;show=0;num=true;}
            else if(butn==button[2]) ...{ 
                right=0; result=0;
                show=0;num=true;
            }
            else if(butn==button[3]) save=false;
            else if(butn==button[4]||butn==button[5]||butn==button[6]||butn==button[10]||
butn==button[11]||butn==button[12]||butn==button[16]||butn==button[17]||
butn==button[18]||butn==button[22]||butn==button[24])...{
                if(butn==button[24]) dolt=true;
                if(num) ...{
                    String sf1=butn.getText();
                    right=Double.parseDouble(sf1);
                    show=right;num=false;
                }
                else ...{  
                    StringBuffer sf;
                    if(!dolt)...{ 
                        int tm=(int) right;
                        sf=new StringBuffer(new Integer(tm).toString());
                    }
                    else...{ 
                        sf=new StringBuffer(new Double(right).toString());
                    }    
                    sf.append(butn.getText());
                    right=Double.parseDouble(sf.toString());
                    show=right;num=false;
                }
            }
            else if(butn==button[7]||butn==button[13]||butn==button[19]||butn==button[25]||butn==button[26])...{
                    num=true;    
                if(op==0) ...{ result=right;show = result;}
                else ...{
                    switch(op)...{
                        case '*': result*=right;break;
                        case '/': result/=right;break;
                        case '-': result-=right;break;
                        case '+': result+=right;break;
                    }
                    show=result;
                }
                if(butn==button[7]) op='/';
                else if(butn==button[13]) op='*';
                else if(butn==button[19]) op='-';
                else if(butn==button[25]) op='+';
                
            }
            else if(butn==button[8])...{ 
                num=true;
                right=Math.sqrt(right);
                show =right;
            }
            else if(butn==button[9]) ...{ num=true;right=saveResult;show=right;}
            else if(butn==button[14])...{ num=true;right/=100;show=right; }
            else if(butn==button[15])...{ num=true;save=true;saveResult=show;}
            else if(butn==button[20])...{ num=true;right=1/right; show=right;}
            else if(butn==button[21])...{ 
                num=true;
                if(show==right) saveResult+=right;
                else saveResult*=2;
            }
            else if(butn==button[23])...{
                if(show==right) right*=-1;
                else result*=-1;
                show*=-1;
            }
            if(save)
                text.setText("M "+new Double(show).toString()); 
            else text.setText(new Double(show).toString());
        }
    }
    public static void main(String[] args)...{
        jsq test=new jsq();
    }
}