自己写的一个计算器，极其简单，并且很多功能不完备

其实贴上来的代码都会有点搞笑，学了Java不过个把月，写的完全不知所云，很多基本知识还是不是很透彻，就当这段路上的勉励站吧，再接再厉！

要是不幸污了您的眼睛，别见怪啊还望求教，指点一下，我也能进步进步，很多东西都是书上学不到的。

/**
 * 做一个计算器，使其具有简单的功能
 * @author：JeremyJone
 * @2014.9.24
 * 
 * 做出界面，具有显示面板，同时具有0-9，和加减乘除，还有删除和清空按钮
 * 
 * 按下每个按钮时显示面板都具有相应功能
 * 
 */

package Demo1;

import javax.swing.*;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class calculator extends JFrame implements ActionListener{
	
	
	String s="";
	//定义两个中间缓存变量
	double p1;
	double p2;
	
	//在定义一个加减乘除的符号变量，0 代表无表示，1代表加，2代表减，3代表乘，4代表除
	int x=0;
	
	
	JTextField text=null;
	
	JButton jbc=null;
	JButton jb1=null;
	JButton jb2=null;
	JButton jb3=null;
	JButton jb4=null;
	JButton jb5=null;
	JButton jb6=null;
	JButton jb7=null;
	JButton jb8=null;
	JButton jb9=null;
	JButton jb0=null;
	JButton jbdot=null;
	JButton jbe=null;
	JButton jbadd=null;
	JButton jbminus=null;
	JButton jbtime=null;
	JButton jbdivide=null;
	

	public static void main(String[] args) {
		// TODO Auto-generated method stub

		calculator demo1_1=new calculator();		
	}

	//构造
	public calculator()
	{
		JPanel mainpanel=new JPanel();
		
		JPanel northpanel=new JPanel();
		text=new JTextField();
		text.setPreferredSize(new Dimension(135,50)); 
		text.setEnabled(false);
		text.setFont(new Font("黑体",30,30));
		text.setHorizontalAlignment(JTextField.RIGHT);   //右对齐
		
		jbc=new JButton("C");	
		jbc.setPreferredSize(new Dimension(50,50));
		jbc.addActionListener(this);
		jbc.setActionCommand("C");
		
		northpanel.add(text);
		northpanel.add(jbc);
		
		JPanel buttonpanel=new JPanel(new GridLayout(4,3,10,10));	
		jb1=new JButton("1");
		jb1.addActionListener(this);
		jb1.setActionCommand("1");
		
		jb2=new JButton("2");
		jb2.addActionListener(this);
		jb2.setActionCommand("2");
		
		jb3=new JButton("3");
		jb3.addActionListener(this);
		jb3.setActionCommand("3");
		
		jb4=new JButton("4");
		jb4.addActionListener(this);
		jb4.setActionCommand("4");
		
		jb5=new JButton("5");
		jb5.addActionListener(this);
		jb5.setActionCommand("5");
		
		jb6=new JButton("6");
		jb6.addActionListener(this);
		jb6.setActionCommand("6");
		
		jb7=new JButton("7");
		jb7.addActionListener(this);
		jb7.setActionCommand("7");
		
		jb8=new JButton("8");
		jb8.addActionListener(this);
		jb8.setActionCommand("8");
		
		jb9=new JButton("9");
		jb9.addActionListener(this);
		jb9.setActionCommand("9");
		
		jb0=new JButton("0");
		jb0.addActionListener(this);
		jb0.setActionCommand("0");
		
		jbdot=new JButton(".");
		jbdot.addActionListener(this);
		jbdot.setActionCommand("dot");
		
		jbe=new JButton("=");
		jbe.addActionListener(this);
		jbe.setActionCommand("e");
		
		
		JPanel mathpanel=new JPanel(new GridLayout(4,1,10,10));
		jbadd=new JButton("+");
		jbadd.addActionListener(this);
		jbadd.setActionCommand("add");
		
		jbminus=new JButton("-");
		jbminus.addActionListener(this);
		jbminus.setActionCommand("minus");
		
		jbtime=new JButton("*");
		jbtime.addActionListener(this);
		jbtime.setActionCommand("time");
		
		jbdivide=new JButton("/");
		jbdivide.addActionListener(this);
		jbdivide.setActionCommand("divide");
		
		
		buttonpanel.add(jb7);
		buttonpanel.add(jb8);
		buttonpanel.add(jb9);
		buttonpanel.add(jb4);
		buttonpanel.add(jb5);
		buttonpanel.add(jb6);
		buttonpanel.add(jb1);
		buttonpanel.add(jb2);
		buttonpanel.add(jb3);
		buttonpanel.add(jbdot);
		buttonpanel.add(jb0);
		buttonpanel.add(jbe);
		
		mathpanel.add(jbadd);
		mathpanel.add(jbminus);
		mathpanel.add(jbtime);
		mathpanel.add(jbdivide);
		
		
		mainpanel.add(northpanel);
		mainpanel.add(buttonpanel,BorderLayout.WEST);
		mainpanel.add(mathpanel,BorderLayout.EAST);
		
		text.setText(s);
		
		this.add(mainpanel);
		this.setLocation(700, 300);
		this.setSize(220, 250);
		this.setResizable(false);
		this.setVisible(true);
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		
	}

	@Override
	public void actionPerformed(ActionEvent e)  {
		// TODO Auto-generated method stub
		
		try {
			
			if(e.getActionCommand().equals("C"))
			{
				s="";
				text.setText(s);
			}		
			else if(e.getActionCommand().equals("1"))
			{
				s=s+"1";
				text.setText(s);
			}
			else if(e.getActionCommand().equals("2"))
			{
				s=s+"2";
				text.setText(s);
			}
			else if(e.getActionCommand().equals("3"))
			{
				s=s+"3";
				text.setText(s);
			}
			else if(e.getActionCommand().equals("4"))
			{
				s=s+"4";
				text.setText(s);
			}
			else if(e.getActionCommand().equals("5"))
			{
				s=s+"5";
				text.setText(s);
			}
			else if(e.getActionCommand().equals("6"))
			{
				s=s+"6";
				text.setText(s);
			}
			else if(e.getActionCommand().equals("7"))
			{
				s=s+"7";
				text.setText(s);
			}
			else if(e.getActionCommand().equals("8"))
			{
				s=s+"8";
				text.setText(s);
			}
			else if(e.getActionCommand().equals("9"))
			{
				s=s+"9";
				text.setText(s);
			}
			else if(e.getActionCommand().equals("0"))
			{
				s=s+"0";
				text.setText(s);
			}
			else if(e.getActionCommand().equals("dot"))
			{
				if (text.getText().contains("."))
				{
					s=s;
					text.setText(s);
				}else
				{
					s=s+".";
					text.setText(s);
				}
			}
			else if(e.getActionCommand().equals("e"))
			{
				switch(x)
				{
				case 0:
					text.setText(s);
					break;
				case 1:
					p2=Double.valueOf(text.getText());
					s=String.valueOf(p1+p2);					
					text.setText(s);					
					break;
				case 2:
					p2=Double.valueOf(text.getText());
					s=String.valueOf(p1-p2);
					text.setText(s);
					break;
				case 3:
					p2=Double.valueOf(text.getText());
					s=String.valueOf(p1*p2);
					text.setText(s);
					break;
				case 4:
					p2=Double.valueOf(text.getText());
					if(p2!=0)
					{
						s=String.valueOf(p1/p2);
						text.setText(s);
					}else
					{
						s="ERROR";
						text.setText(s);
					}
					break;
				}
			}
			else if(e.getActionCommand().equals("add"))
			{
				p1=Double.valueOf(text.getText());
				s="";
				x=1;
			}
			else if(e.getActionCommand().equals("minus"))
			{
				p1=Double.valueOf(text.getText());
				s="";
				x=2;
			}
			else if(e.getActionCommand().equals("time"))
			{
				p1=Double.valueOf(text.getText());
				s="";
				x=3;
			}
			else if(e.getActionCommand().equals("divide"))
			{
				p1=Double.valueOf(text.getText());
				s="";
				x=4;
			}
			
		} catch (Exception e2) {
			// TODO: handle exception
			e2.printStackTrace();
		}
		
		
	}

}