calculator.java

用Java编写一个简易计算器

import java.awt.*; 
import java.awt.event.*; 
public class Calculator extends WindowAdapter implements ActionListener{ 
private double result=0,data1=0,radixPointDepth=1; 
private boolean radixPointIndicate=false,resultIndicate=false; 
private char prec='+'; 
private Frame f; 
private TextField tf; 
private Button b1,b2,b3,b4,b5,b6,b7,b8,b9,b10,b11,b12,b13,b14,b15,b16,b17; 
private Panel p,p1; 
static public void main(String args[]){ 
Calculator de=new Calculator(); 
de.go(); 
} 
public void go(){ 
f=new Frame("计算器"); 
p=new Panel();
p1=new Panel(); 
p.setLayout(new GridLayout(4,4)); 
tf=new TextField(30); 
b1=new Button("7"); 
b2=new Button("8"); 
b3=new Button("9"); 
b4=new Button("+"); 
b5=new Button("4"); 
b6=new Button("5"); 
b7=new Button("6"); 
b8=new Button("-"); 
b9=new Button("1"); 
b10=new Button("2"); 
b11=new Button("3"); 
b12=new Button("*"); 
b13=new Button("0"); 
b14=new Button("."); 
b15=new Button("="); 
b16=new Button("/");
b17=new Button("清除"); 
f.add(p1,"North");
p1.add(tf);
p1.add(b17); 
f.add(p,"Center"); 
p.add(b1); 
p.add(b2); 
p.add(b3); 
p.add(b4); 
p.add(b5); 
p.add(b6); 
p.add(b7); 
p.add(b8); 
p.add(b9); 
p.add(b10); 
p.add(b11); 
p.add(b12); 
p.add(b13); 
p.add(b14); 
p.add(b15); 
p.add(b16); 
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); 
b10.addActionListener(this); 
b11.addActionListener(this); 
b12.addActionListener(this); 
b13.addActionListener(this); 
b14.addActionListener(this); 
b15.addActionListener(this); 
b16.addActionListener(this);
b17.addActionListener(this); 
f.addWindowListener(this); 
f.setSize(300,200); 
f.setVisible(true); 
} 
public void actionPerformed(ActionEvent e){ 
String s; 
s=e.getActionCommand();
if(s=="清除")
{tf.setText("0.0");
data1=0;
result=0;
radixPointIndicate=false;
radixPointDepth=1;} 
  switch(s.charAt(0)){ 
    case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': 
      Integer Int1=new Integer(s); 
      if(radixPointIndicate){ 
        radixPointDepth=radixPointDepth/10; 
        data1=data1+(Int1.intValue())*radixPointDepth; 
        } 
      else{ 
        data1=data1*10+(Int1.intValue()); 
        } 
      Double displayNumber=new Double(data1); 
      tf.setText(displayNumber.toString());  
      break;
   case '+': case '-':case '*':case '/':case '=':
      radixPointIndicate=false;
      radixPointDepth=1;
      if(resultIndicate){
        radixPointIndicate=false; 
        result=data1;
        if(e.getActionCommand()=="*"||e.getActionCommand()=="/")
        data1=1;
        else data1=0;
        resultIndicate=false; 
        }   
     else{ 
     switch(prec){ 
       case '+': 
       result=result+data1; 
       radixPointDepth=1;
       break; 
       case '-': 
       result=result-data1; 
       radixPointDepth=1;
       break; 
       case '*': 
       result=result*data1; 
       radixPointDepth=1;
       break; 
       case '/': 
       result=result/data1; 
       radixPointDepth=1;
       break; 
       }   
    } 
    if(s.charAt(0)!='='){ 
      data1=0; 
      prec=s.charAt(0); 
      } 
   if(s.charAt(0)=='='){
    data1=0; 
    displayNumber=new Double(result); 
    tf.setText(displayNumber.toString());  
    resultIndicate=true; 
      } 
     break; 
    case '.': 
    radixPointIndicate=true; 
    break; 
  } 
} 
public void windowClosing(WindowEvent e){ 
System.exit(0); 
} 
}