jsp.java

简单的记事本java程序 请大家多多帮忙指点

package myjsp;

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

class Myframe extends JFrame implements ActionListener
{
	private JTextField resultField = new JTextField("0");
	private boolean end,add,sub,mul,div;
	private String str;
	private double num1,num2;
	private JButton reset = new JButton("归零");
	private JButton b1 = new JButton("1");	
	private JButton b2 = new JButton("2");
	private JButton b3 = new JButton("3");
	private JButton b4 = new JButton("4");
	private JButton b5 = new JButton("5");
	private JButton b6 = new JButton("6");
	private JButton b7 = new JButton("7");
	private JButton b8 = new JButton("8");
	private JButton b9 = new JButton("9");
	private JButton b0 = new JButton("0");
	private JButton bPlus = new JButton("+");
	private JButton bMinus = new JButton("-");
	private JButton bMultiple = new JButton("*");
	private JButton bDivide = new JButton("/");
	private JButton bEqual = new JButton("=");
	private JButton bDot = new JButton(".");
	public Myframe()
	{
	}
	public Myframe(String title)
	{
		super(title);
		this.setSize(300,200);
		this.setLocation(150,150);
		this.setResizable(false);
		BorderLayout bl1 = new BorderLayout(5,5);
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.setLayout(bl1);
		
		//设置文本显示区
		resultField = new JTextField("0");;
		resultField.setSize(400,50);
		resultField.setHorizontalAlignment(JTextField.RIGHT );
		this.add(BorderLayout.NORTH,resultField);
		JPanel bPanel = new JPanel();
		this.add(BorderLayout.SOUTH,reset);
		this.add(BorderLayout.CENTER,bPanel);
		GridLayout gl1 = new GridLayout(4,4,5,5);
		bPanel.setLayout(gl1);
		//添加按钮
		//Font f11 = new Font();		
		b1.setForeground(Color.blue);
		Font f1 =new Font("Brush Script MT",Font.BOLD ,20);
		b1.setFont(f1);
		b2.setFont(f1);
		
		//b1.setFont(f11.ITALIC);
		b1.addActionListener(this);
		b2.addActionListener(this);
		b3.addActionListener(this);
		b4.addActionListener(this);
		b5.addActionListener(this);
		b6.addActionListener(this);
		b7.addActionListener(this);
		b8.addActionListener(this);
		b9.addActionListener(this);
		b0.addActionListener(this);	
		bDot.addActionListener(this);
		bEqual.addActionListener(this);
		bPlus.addActionListener(this);	
		bMultiple.addActionListener(this);
		bDivide.addActionListener(this);
		reset.addActionListener(this);
		
		
		bPanel.add(b1);
		bPanel.add(b2);
		bPanel.add(b3);
		bPanel.add(bPlus);
		bPanel.add(b4);
		bPanel.add(b5);
		bPanel.add(b6);
		bPanel.add(bMinus);
		bPanel.add(b7);
		bPanel.add(b8);
		bPanel.add(b9);
		bPanel.add(bMultiple);
		bPanel.add(bDot);
		bPanel.add(b0);
		bPanel.add(bEqual);
		bPanel.add(bDivide);
		add(BorderLayout.CENTER, bPanel);			
		
	}

	public void num(int i){
		  String s = null;
		  s=String.valueOf(i);
		  if(end){
		   //如果数字输入结束，则将文本框置零，重新输入
		    resultField.setText("0");
		    end=false;
		   
		    }
		  if((resultField.getText()).equals("0")){
		   //如果文本框的内容为零，则覆盖文本框的内容
		   resultField.setText(s);
		   
		   }
		  else{
		    //如果文本框的内容不为零，则在内容后面添加数字
		    str = resultField.getText() + s;
		    resultField.setText(str);
		    
		    }
		 }
		 
		public void actionPerformed(ActionEvent e){ //数字事件
		    if(e.getSource()==b1)
		     num(1);
		    else if(e.getSource()==b2)
		    num(2);
		    else if(e.getSource()==b3)
		    num(3);
		    else if(e.getSource()==b4)
		    num(4);
		    else if(e.getSource()==b5)
		    num(5);
		    else if(e.getSource()==b6)
		    num(6);
		    else if(e.getSource()==b7)
		    num(7);
		    else if(e.getSource()==b8)
		    num(8);
		    else if(e.getSource()==b9)
		    num(9);
		    else if(e.getSource()==b0)
		    num(0); 
		    
		    //符号事件  
		    else if(e.getSource()==bPlus)
		    sign(1);
		    else if(e.getSource()==bMinus)
		    sign(2);
		    else if(e.getSource()==bMultiple)
		    sign(3);
		    else if(e.getSource()==bDivide)
		    sign(4);
		    
		    //重置按钮
		    else if(e.getSource() == reset)
		    res(5);
		    
		    //等号
		    else if(e.getSource()==bDot){
		    str=resultField.getText();
		    if(str.indexOf(".")<=1){
		     str+=".";
		     resultField.setText(str);
		     }
		    }
		    else if(e.getSource()==bEqual){
		    num2=Double.parseDouble(resultField.getText());



		    if(add){
		     num1=num1 + num2;}
		    else if(sub){
		     num1=num1 - num2;}
		    else if(mul){
		     num1=num1 * num2;}
		    else if(div){
		     num1=num1 / num2;} 
		  resultField.setText(String.valueOf(num1));
		  end=true;   
		  }   
		    
		                         
		  }
		public void res(int n)
		{
			resultField.setText("0");
		}
		public void sign(int s){
		   if(s==1){
		    add=true;
		    sub=false;
		    mul=false;
		    div=false;
		    }
		    else if(s==2){
		     add=false;
		     sub=true;
		     mul=false;
		     div=false;
		     }
		    else if(s==3){
		     add=false;
		     sub=false;
		     mul=true;
		     div=false;
		      }
		    else if(s==4){
		     add=false;
		     sub=false;
		     mul=false;
		     div=true;
		     } 
		  num1=Double.parseDouble(resultField.getText());
		  end=true;
		 }    
}


class MyTest {
	
	public static void main(String[] args) {
		Myframe mf = new Myframe("计算器");
		mf.setVisible(true);		
	}

}