wuwei.java

JAVA计算器

//Wuwei.java
import java.awt.*;
import java.io.*;
import java.applet.*;
import javax.swing.*;
import java.awt.event.*;
import javax.swing.event.*;
import java.lang.*;
import javax.swing.JApplet.*;

public class Wuwei extends JApplet
 {
  Mypanel1 panel1=new Mypanel1(this);
  Mypanel2 panel2=new Mypanel2(this);
  public JTextField textField1=new JTextField(20);
  public void init()
{ 
  Container con=getContentPane();
  con.setLayout(new BorderLayout());
  setSize(360,190);
  con.add(textField1,BorderLayout.NORTH);
  //textField1.setEditable(false);	
  con.add(panel1,BorderLayout.CENTER);//CE,C,Backspace,1-9
  con.add(panel2,BorderLayout.WEST);//MS,MR,MC,M+
}

 class Mypanel1 extends JApplet implements ActionListener
{
	 double vard,vard1,result=0;//保存中间值(vard)和最后结果(result)
    int key,presskey;//用来保存当前所进行的运算(key)和前一次所进行的运算(presskey)
    JPanel panel11=new JPanel(new GridLayout(5,5)); 
 //设计
    JLabel label=new JLabel("    ");
    JLabel label1=new JLabel("    ");
    JButton button0=new JButton("0");
    JButton button1=new JButton("1");
    JButton button2=new JButton("2");
    JButton button3=new JButton("3");
    JButton button4=new JButton("4");
    JButton button5=new JButton("5");
    JButton button6=new JButton("6");
    JButton button7=new JButton("7");
    JButton button8=new JButton("8");
    JButton button9=new JButton("9");  
    JButton buttonAdd=new JButton("+");
    JButton buttonSub=new JButton("-");
    JButton buttonDiv=new JButton("/");
    JButton buttonMul=new JButton("*");
    JButton buttonEqual=new JButton("=");
    JButton buttonSqrt=new JButton("sqrt");
    JButton buttonMod=new JButton("%");
    JButton buttonDaoShu=new JButton("1/X ");
    JButton buttonAS=new JButton("+/- ");
    JButton buttonDot=new JButton(".");
    JButton buttonBackspace=new JButton("退格");
    JButton buttonCE=new JButton("CE");
    JButton buttonC=new JButton("C");
   Mypanel1(Container con1){
 con1=getContentPane();
 con1.setLayout(new FlowLayout());
 con1.add(panel11);
 panel11.add(label);
 panel11.add(label1);
 panel11.add(buttonBackspace);
 buttonBackspace.addActionListener(this);
 buttonBackspace.setForeground(Color.red);
 panel11.add(buttonCE);
 buttonCE.addActionListener(this);
 buttonCE.setForeground(Color.red);
 panel11.add(buttonC);
 buttonC.addActionListener(this);
 buttonC.setForeground(Color.red);
 panel11.add(button7);
 button7.addActionListener(this);
 button7.setForeground(Color.blue);
 panel11.add(button8);
 button8.addActionListener(this);
 button8.setForeground(Color.blue);
 panel11.add(button9);
 button9.addActionListener(this);
 button9.setForeground(Color.blue);
 panel11.add(buttonDiv);
 buttonDiv.addActionListener(this);
 buttonDiv.setForeground(Color.red);
 panel11.add(buttonSqrt);
 buttonSqrt.addActionListener(this);
 buttonSqrt.setForeground(Color.blue);
 panel11.add(button4);
 button4.addActionListener(this);
 button4.setForeground(Color.blue);
 panel11.add(button5);
 button5.addActionListener(this);
 button5.setForeground(Color.blue);
 panel11.add(button6);
 button6.addActionListener(this);
 button6.setForeground(Color.blue);
 panel11.add(buttonMul);
 buttonMul.addActionListener(this);
 buttonMul.setForeground(Color.red);
 panel11.add(buttonMod);
 buttonMod.addActionListener(this);
 buttonMod.setForeground(Color.blue);
 panel11.add(button1);
 button1.addActionListener(this);
 button1.setForeground(Color.blue);
 panel11.add(button2);
 button2.addActionListener(this);
 button2.setForeground(Color.blue);
 panel11.add(button3);
 button3.addActionListener(this);
 button3.setForeground(Color.blue);
 panel11.add(buttonSub);
 buttonSub.addActionListener(this);
 buttonSub.setForeground(Color.red);
 panel11.add(buttonDaoShu);
 buttonDaoShu.addActionListener(this);
 buttonDaoShu.setForeground(Color.blue);  
 panel11.add(button0);
 button0.addActionListener(this);
 button0.setForeground(Color.blue);
 panel11.add(buttonAS);
 buttonAS.addActionListener(this);
 buttonAS.setForeground(Color.blue);
 panel11.add(buttonDot);
 buttonDot.addActionListener(this);
 buttonDot.setForeground(Color.blue);
 panel11.add(buttonAdd);
 buttonAdd.addActionListener(this);
 buttonAdd.setForeground(Color.red);
 panel11.add(buttonEqual);
 buttonEqual.addActionListener(this);
 buttonEqual.setForeground(Color.red);
 setSize(50,80);
 }  
public void actionPerformed(ActionEvent e)
{
  Object temp=e.getSource();
  if(temp==button0){
  	textField1.setText(textField1.getText()+Integer.toString(0));
  	} 
  if(temp==button1){
  	textField1.setText(textField1.getText()+Integer.toString(1));
  	} 
  if(temp==button2){
  	textField1.setText(textField1.getText()+Integer.toString(2));
  	} 
  if(temp==button3){
  	textField1.setText(textField1.getText()+Integer.toString(3));
  	} 
  if(temp==button4){
  	textField1.setText(textField1.getText()+Integer.toString(4));
  	} 
  if(temp==button5){
  	textField1.setText(textField1.getText()+Integer.toString(5));
  	} 
  if(temp==button6){
  	textField1.setText(textField1.getText()+Integer.toString(6));
  	} 
  if(temp==button7){
  	textField1.setText(textField1.getText()+Integer.toString(7));
  	}  
  if(temp==button8){
  	textField1.setText(textField1.getText()+Integer.toString(8));
  	} 
  if(temp==button9){
  	textField1.setText(textField1.getText()+Integer.toString(9));
  	} 
  //按下'.'按钮时，判断当前文本框内字符串中含不含'.'，如果已含，则不允许再插入'.'
  if(temp==buttonDot){
    boolean isDot=false;
    if(textField1.getText().length()==0)
      isDot=true;
    for(int i=0;i<textField1.getText().length();i++){
       if('.'==textField1.getText().charAt(i)){
       	 isDot=true;
       	 break;
       	 }
      }
    if(isDot==false)
       textField1.setText(textField1.getText()+'.');
       }
    if(temp==buttonAdd){
   	 presskey=key=0;
   	 vard=Double.parseDouble(textField1.getText());
   	 textField1.setText("");
   	 result+=vard;
   	    }
     if(temp==buttonSub){
   	  presskey=key=1;
   	  vard=Double.parseDouble(textField1.getText());
   	 textField1.setText("");
      result-=vard;
   	   	   	}
   	 if(temp==buttonMul){
   	presskey=key=2;
   	vard=Double.parseDouble(textField1.getText());
   	 textField1.setText("");
      result=vard;
   	        }
     if(temp==buttonDiv){
    presskey=key=3;
    vard=Double.parseDouble(textField1.getText());
   	 textField1.setText("");
   	   result=vard;
   	   }
     if((presskey==0||presskey==1||presskey==2||presskey==3)&&presskey!=4){   
   	   vard1=Double.parseDouble(textField1.getText());//取第二个操作数	
    }
   	 if(temp==buttonEqual){
   	  vard=Double.parseDouble(textField1.getText());
   	   if(presskey==0)
   	  result+=vard;
   	  if(presskey==1)
   	  result-=vard;
   	  if(presskey==2)
   	  result*=vard;
   	  if(presskey==3){
   	  if(vard==0)
   	  	textField1.setText("除数不能为0");
   	    else
   	   result/=vard;
   	      }
      if(presskey==4){
        if(key==0)
        result+=vard1;
        if(key==1)
        result-=vard1;
        if(key==2)
        result*=vard1;
        if(key==3){
          if(vard1==0)
           textField1.setText("除数不能为0");
           else
           result/=vard1;
            }
    }
       //判断是否输出结果
       if(presskey!=3 || key!=3)
        textField1.setText(Double.toString(result));
        else{
           if(vard!=0 || vard1!=0)
             textField1.setText(Double.toString(result));
            }
        presskey=4;
   	  	   	}
      //按下'Backspace'键，利用循环将当前字符串中的最后一个字母删除
      if (temp == buttonBackspace) {
        String s = textField1.getText();
        textField1.setText("");
        for (int i = 0; i < s.length() - 1; i++) {
          char a = s.charAt(i);
          textField1.setText(textField1.getText() + a);
        }
      }
      //按下'CE'按钮，将当前文本框内数据清除
      if (temp == buttonCE) {
        textField1.setText("");
          }
      //按下'C'按钮，文本框内数据清除，同时var,answer清0
      if (temp == buttonC) {
        vard =result=vard1=0;
        textField1.setText("");
         }
       if(temp==buttonSqrt){
       	String s=textField1.getText();
       	if(s.charAt(0)=='-')
       	  textField1.setText("负数不能开平方");  
       	 else
       	 textField1.setText(Double.toString(java.lang.Math.sqrt(Double.parseDouble(textField1.getText()))));
      }
      if(temp==buttonMod){
        boolean isDot=false;
        String s=textField1.getText();
        for(int i=0;i<s.length();i++)
        	if(s.charAt(i)=='.'){
              isDot=true;
              break;
              }
        if(isDot=true)
         textField1.setText(Double.toString(Double.parseDouble(s)/100.0));
        else
         {
          if(Integer.parseInt(s)%100==0)
            textField1.setText(Integer.toString(Integer.parseInt(s)/100));
          else
            textField1.setText(Double.toString(Double.parseDouble(s)/100.0));
            }  
      }
      //按下'+/-'按钮时处理
      if(temp==buttonAS){
          String s = textField1.getText();
          //如果当前字符串第一个字符不是符号，则添加一个符号在首字母处
            if (s.charAt(0)!='-') {
             textField1.setText('-' + s);
            }
        //如果当前字符串首字母有'-'号,代表现在是个负数,再按下时,则将首符号去掉
          if (s.charAt(0) == '-') {
            textField1.setText("");
            textField1.setText(s.substring(1));
            }
           }
      if(temp==buttonDaoShu){
         if(Double.parseDouble(textField1.getText())==0)
         	textField1.setText("0不能求倒数");
        else
          textField1.setText(Double.toString(1/Double.parseDouble(textField1.getText())));
          }
   	  }
}
class Mypanel2 extends JApplet implements ActionListener
{  
    double memoryd;//内存中存储的double型数据
    int memoryi;//内存中存储的int型数据
   JTextField textField2=new JTextField();
   JPanel panel22=new JPanel(new GridLayout(5,1));
   JButton buttonMR=new JButton("MR");
   JButton buttonMC=new JButton("MC");
   JButton buttonMS=new JButton("MS");
   JButton buttonM=new JButton("M+");
   Mypanel2(Container con2){
  con2=getContentPane();
  con2.setLayout(new FlowLayout());
  con2.add(panel22);
  panel22.add(textField2);
  textField2.setEditable(false);
  panel22.add(buttonMC);
  buttonMC.addActionListener(this);
  buttonMC.setForeground(Color.red);
  panel22.add(buttonMR);
  buttonMR.addActionListener(this);
  buttonMR.setForeground(Color.red);
  panel22.add(buttonMS);
  buttonMS.addActionListener(this);
  buttonMS.setForeground(Color.red);
  panel22.add(buttonM);
  buttonM.addActionListener(this);
  buttonM.setForeground(Color.red);
 }
public void actionPerformed(ActionEvent e){
	//计算器有关内存操作
	Object temp=e.getSource();
      //'MC'的操作，将内存清0
      if (temp == buttonMC) {
        memoryd = memoryi = 0;
        textField2.setText("");
      }
      //'MS'的操作，将当前文本框内容保存入内存，显示'M'
      if (temp == buttonMS) {
        boolean isDot = false;
        textField2.setText("      M");
        for (int i = 0; i <textField1.getText().length(); i++)
          if ('.' == textField1.getText().charAt(i)) {
            isDot = true;
            break;
          }
     //如果是double,则存入memoryd(double存储器)
        if (isDot == true) {
          memoryd = Double.parseDouble(textField1.getText());
          memoryi = 0; //保证存储器中存放最新的值
        }
        //如果是int,则存入memoryi(int存储器)
        else {
          memoryi = Integer.parseInt(textField1.getText());
          memoryd = 0; //保证存储器中存放最新的值
        }
      }
      //'MR'的操作，将存储器中的信息输出
      if (temp == buttonMR) {
        if (memoryd != 0)
          textField1.setText(Double.toString(memoryd));
        if (memoryi != 0)
          textField1.setText(Integer.toString(memoryi));
      }
      //'M+'的功能，将当前文本框里的数据和存储器中数据相加后，再存入存储器
      if (temp == buttonM) {
        boolean isDot = false;
        for (int i = 0; i <textField1.getText().length(); i++)
          if ('.' == textField1.getText().charAt(i)) {
            isDot = true;
            break;
          }
        if (memoryi != 0)
         { //存储中是一个int型数
          if (isDot == false) //被加数是一个int型数
            memoryi += Integer.parseInt(textField1.getText());
            else
             { //被加数是一个double型数，则将int存储器中数传入double存储器与当前数相加，int存储器清零
            memoryd = memoryi + Double.parseDouble(textField1.getText());
            memoryi = 0;
          }
        }
        else
          memoryd += Double.parseDouble(textField1.getText());
      }
}
} 
}