calculator.java

网络计算器的ＪＡＶＡ源代码

import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
public class Calculator{
	public static void main(String[]a){
		MyFrame frm=new MyFrame();
		frm.setVisible(true);
	}
}

class MyFrame extends JFrame{
	double operator1,operator2,result;
	char c;
	JButton button1,button2,button3,button4,button5,button6;
	JLabel label;
	JPanel panel1,panel2;
	JTextField text1,text2,text3,text4;
	Container container;
	
	public MyFrame(){
		button1=new JButton("+");
		button2=new JButton("-");
		button3=new JButton("*");
		button4=new JButton("/");
		button5=new JButton("=");
		button6=new JButton("AC");
		label=new JLabel("=");
	    text1=new JTextField(10);
	    text2=new JTextField(10);
	    text3=new JTextField(10);
	    text4=new JTextField(1);
	    panel1=new JPanel();
        panel2=new JPanel();
	    container=getContentPane();
        container.setLayout(new BorderLayout(10,10));
/*	    container.add(text1,getConstraints(0,0,5,1,0,0,GridBagConstraints.CENTER,
	        GridBagConstraints.BOTH,new Insets(0,0,0,0)));
	    container.add(text2,getConstraints(0,2,5,1,0,0,GridBagConstraints.CENTER,
	        GridBagConstraints.BOTH,new Insets(0,0,0,0),0,0  ));
	    container.add(text3,getConstraints(0,3,5,1,0,0,GridBagConstraints.CENTER,
	        GridBagConstraints.BOTH,new Insets(0,0,0,0),0,0  ));
	    container.add(text4,getConstraints(4,1,1,1,0,0,GridBagConstraints.CENTER,
	        GridBagConstraints.BOTH,new Insets(0,0,0,0),0,0  ))
*/
        container.add(panel1,BorderLayout.NORTH);
        container.add(panel2,BorderLayout.SOUTH);
        panel1.setLayout(new FlowLayout(FlowLayout.CENTER,0,10));
		panel2.setLayout(new FlowLayout(FlowLayout.CENTER,0,10));
	    panel1.add(button1);panel1.add(button2);
	    panel1.add(button3);panel1.add(button4);
	    panel1.add(button5);panel1.add(button6);
	    panel2.add(text1);panel2.add(text4);
	    panel2.add(text2);panel2.add(label);panel2.add(text3);
	    text3.setEditable(false);
	    button1.addActionListener(new MyActionListener()); 
	    button2.addActionListener(new MyActionListener()); 
	    button3.addActionListener(new MyActionListener()); 
	    button4.addActionListener(new MyActionListener()); 
	    button5.addActionListener(new MyActionListener());    
	    button6.addActionListener(new MyActionListener());
	        
	    setTitle("Calculator");
        setSize(400,200);  
        setLocation(100,50);
        text1.requestFocus();
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	 }
	 public double MyGetOperator(JTextField text){
	    try{
	    	return Double.parseDouble(text.getText());
	    }
	    catch(NumberFormatException e)
	    {   text.setText("Illegal input!");
	    	repaint();
	    	return -9999.9;
	    }
	 }	  
	 class MyActionListener implements ActionListener{
   	  public void actionPerformed(ActionEvent e){
   	   	if(e.getSource()==button1)
   	   	{
   	   		operator1=MyGetOperator(text1);
   	   		c='+';  text4.setText("+");
   	   		text1.transferFocus();   
   	   		repaint();   
   	   	 }
   	   	else if(e.getSource()==button2)
   	   	{
   	   		operator1=MyGetOperator(text1);
   	   		c='-';  text4.setText("-");
   	   		  
   	   		repaint();  
   	   	}
   	   	else if(e.getSource()==button3)
   	   	{
   	   		operator1=MyGetOperator(text1);
   	   		c='*';  text4.setText("*");
   	   		repaint();
   	   	} 
   	   	else if(e.getSource()==button4)
   	   	{
   	   		operator1=MyGetOperator(text1);
   	   		c='/';  text4.setText("/");   
   	   		repaint();  
   	   	}
   	   	else if(e.getSource()==button5)
   	   	{
   	   		operator2=MyGetOperator(text2);
   	   		if(c=='+') result=operator1+operator2;
   	   		else if(c=='-') result=operator1-operator2;
   	   		else if(c=='*') result=operator1*operator2;
   	   		else if(c=='/') result=operator1/operator2;
   	   		//String aaa=new String(result);
   	   		text3.setText(""+result);
   	   		repaint();
   	   	}
   	   	else if(e.getSource()==button6)
   	   	{
   	   		operator1=0.0;operator2=0.0;
   	   		text1.setText("");
   	   		text2.setText("");
   	   		text3.setText("");
   	   		text4.setText("");
   	   		repaint();
   	   	}
   	 }
    }
}