作业5.2

package case1;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.Scanner;
public class no1 {
    public static void main(String[] args) {
        int x,y;
        String z ,p,p1;
        Scanner inr = new Scanner(System.in);
        BufferedReader in=new BufferedReader(new InputStreamReader(System.in)) ;
        
        System.out.print("请输入第一个数字:") ;
        while(true)
        {
            try
            {
                p=in.readLine();
                //如果转换异常则输入的不是数字
                x=Integer.parseInt(p);
                if(x>0)
                {
                    System.out.println("\n") ;
                }
                break;
            }
            catch(Exception e)
            {
                System.out.println("\n错误") ;
            }
        }
        
        System.out.print("请输入第二个数字:") ;
        while(true)
        {
            
            try
            {
                p1=in.readLine();
                //如果转换异常则输入的不是数字
                y=Integer.parseInt(p1);
                if(y>0)
                {
                    System.out.println("\n") ;
                }
                break;
            }
            catch(Exception e)
            {
                System.out.println("\n错误") ;
            }
        }
        
        System.out.println("请输入运算符(+,-,*,/)：");
        z = inr.nextLine();    
        
        
        System.out.println("\n"+x+" "+z+" "+y+"=");
        no2 test = new no2();
        test.case1(z, x, y);
    }
}


package case1;

public class no2 {
            public void case1(String cc, double a, double b) {
                 jia test1 = new jia();
             if (cc.equals("+")) {
                 
                 
                 test1.jia1(a , b);
                    } 
             else if (cc.equals("-")) {
                 
                 test1.jian1(a , b);
                 
                 }
             else if (cc.equals("*")) {
        
                 test1.chen1(a , b);
                 
                     }
             else if (cc.equals("/")) {
                 
                        if (b != 0) {
                            test1.chu1(a , b);
                            
                         } 
                        else {
                         System.out.println("division by zero！");
                         throw new ArithmeticException();
                    }
                 } 
             else {
                     System.out.println("运算符不符合！");
                 }
            }
    }


package case1;

public class jia {

    /**
     * @param args
     */
     public static  double jia1( double a, double b) {
         double anw=0;
         anw=a+b;
         System.out.println(a +"+"+ b);
         System.out.println(anw);
        return anw;
     }
     
     
     public static  double jian1( double a, double b) {
         double anw=0;
         anw=a-b;
         System.out.println(a +"-"+ b);
         System.out.println(anw);
        return anw;
     }
     
     
     public static  double chen1( double a, double b) {
         double anw=0;
         anw=a*b;
         System.out.println(a +"*"+ b);
         System.out.println(anw);
        return anw;
     }
     
     
     public static  double chu1( double a, double b) {
         double anw=0;
         anw=a/b;
         System.out.println(a +"/"+ b);
         System.out.println(anw);
        return anw;
     }
}


package case1;

import static org.junit.Assert.*;

import org.junit.Test;

public class jiaTest {

    @Test
    public void testJia1() {
        double w;
        jia we=new jia();
        w=jia.jia1(1,2);
    }

    @Test
    public void testJian1() {
        double w;
        jia we=new jia();
        w=jia.jian1(3,1);
    }

    @Test
    public void testChen1() {
        double w;
        jia we=new jia();
        w=jia.chen1(3,1);
    }

    @Test
    public void testChu1() {
        double w;
        jia we=new jia();
        w=jia.chu1(4,2);
    }

}
同伴： 董大为    http://www.cnblogs.com/case1/