简单计算器

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

public class GUI extends JFrame
{
private JButton num1,num2,num3,num4,num5,num6,num7,num8,num0,num9;
private JButton bt1,bt2,bt3,bt4,bt5,bt6;
//private JTextField inputFild;
private JTextArea chatContent1,chatContent2;
private JPanel inputPanel,inputpanel1;
//private JScrollPane shcrollPanel;
//构造函数
public GUI()
{
/*******创建窗口*******/
this.setLayout(new GridLayout(2,1));
this.setTitle("计算器");
this.setSize(400, 500);
this.setLocation(300, 200);
this.setVisible(true);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
gui();
}

public void gui()
{
chatContent1 =new JTextArea(12,34);
chatContent2 =new JTextArea(4,5);
chatContent1.setEditable(false);
chatContent2.setEditable(true);
inputpanel1=new JPanel();
inputpanel1.setLayout(new GridLayout(2,1));
inputpanel1.add(chatContent1);
inputpanel1.add(chatContent2);
inputPanel =new JPanel();
inputPanel.setLayout(new GridLayout(4,4));
num1=new JButton("1");
num2=new JButton("2");
num3=new JButton("3");
num4=new JButton("4");
num5=new JButton("5");
num6=new JButton("6");
num7=new JButton("7");
num8=new JButton("8");
num9=new JButton("9");
num0=new JButton("0");
bt1 =new JButton("+");
bt2 =new JButton("-");
bt3 =new JButton("*");
bt4 =new JButton("/");
bt5 =new JButton("=");
bt6 =new JButton(".");
inputPanel.add(num7);
inputPanel.add(num8);
inputPanel.add(num9);
inputPanel.add(bt1);
inputPanel.add(num4);
inputPanel.add(num5);
inputPanel.add(num6);
inputPanel.add(bt2);
inputPanel.add(num1);
inputPanel.add(num2);
inputPanel.add(num3);
inputPanel.add(bt3);
inputPanel.add(bt6);
inputPanel.add(num0);
inputPanel.add(bt5);
inputPanel.add(bt4);
this.add(inputpanel1);
this.add(inputPanel);
color();//  为按钮设置颜色和大小
Action();//为按钮添加监听器

}
//为按钮添加监听器
public void Action()
{

num1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(num1.getText()=="1")
chatContent2.append(num1.getText());
}
}
);
num2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(num2.getText()=="2")
chatContent2.append(num2.getText());
}
}
);
num3.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(num3.getText()=="3")
chatContent2.append(num3.getText());
}
}
);
num4.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(num4.getText()=="4")
chatContent2.append(num4.getText());
}
}
);
num5.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(num5.getText()=="5")
chatContent2.append(num5.getText());
}
}
);
num6.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(num6.getText()=="6")
chatContent2.append(num6.getText());
}
}
);
num7.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(num7.getText()=="7")
chatContent2.append(num7.getText());
}
}
);
num8.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(num8.getText()=="8")
chatContent2.append(num8.getText());
}
}
);
num9.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(num9.getText()=="9")
chatContent2.append(num9.getText());
}
}
);
num0.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(num0.getText()=="0")
chatContent2.append(num0.getText());
}
}
);
bt1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(bt1.getText()=="+")
chatContent2.append(bt1.getText());
}
}
);
bt2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(bt2.getText()=="-")
chatContent2.append(bt2.getText());
}
}
);
bt3.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(bt3.getText()=="*")
chatContent2.append(bt3.getText());
}
}
);
bt4.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(bt4.getText()=="/")
chatContent2.append(bt4.getText());
}
}
);
bt6.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
if(bt6.getText()==".")
chatContent2.append(bt6.getText());
}
}
);
bt5.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
String  str=chatContent2.getText();
if(bt5.getText()=="=")
chatContent2.append(bt5.getText());
double a,b,c;
int num=0,num1=1;
String str1,str2;
for(int i=0;i<str.length();i++)
{
if(str.charAt(i)>='0'&&str.charAt(i)<='9'||str.charAt(i)=='.')
num++;
else
break;
}
for(int j=0;j<str.length();j++)
if(str.charAt(j)=='.')
{
num1=0;
break;
}
str1=str.substring(0,num);
str2=str.substring(num+1);
a=Double.parseDouble(str1);
b=Double.parseDouble(str2);
if(str.charAt(num)=='+')
{
c=a+b;
if(num1==1)
{
long n;
n=(long)(a+b);
chatContent2.append(Long.toString(n));
}
else
chatContent2.append(Double.toString(c));

}
if(str.charAt(num)=='-')
{
c=a-b;
if(num1==1)
{
long n;
n=(long)(a-b);
chatContent2.append(Long.toString(n));
}
else
chatContent2.append(Double.toString(c));
}
if(str.charAt(num)=='*')
{
c=a*b;
if(num1==1)
{
long n;
n=(long)(a*b);
chatContent2.append(Long.toString(n));
}
else
chatContent2.append(Double.toString(c));
}
if(str.charAt(num)=='/')
{
c = a/b;
chatContent2.append(Double.toString(c));
}
chatContent1.setText("");
chatContent1.append(chatContent2.getText());
chatContent2.setText("");
}
}
);
}
//  为按钮设置颜色和大小
public void color()
{
num1.setBackground(Color.white);
num2.setBackground(Color.white);
num3.setBackground(Color.white);
num4.setBackground(Color.white);
num5.setBackground(Color.white);
num6.setBackground(Color.white);
num7.setBackground(Color.white);
num8.setBackground(Color.white);
num9.setBackground(Color.white);
num0.setBackground(Color.white);
bt1.setBackground(Color.LIGHT_GRAY);
bt2.setBackground(Color.LIGHT_GRAY);
bt3.setBackground(Color.LIGHT_GRAY);
bt4.setBackground(Color.LIGHT_GRAY);
bt5.setBackground(Color.white);
bt6.setBackground(Color.white);
bt5.setFont(new Font("黑体",Font.BOLD,40));
}
public static void main(String[] args) {
new GUI();
}
}