第10次作业

题目1：

编写一个应用程序，模拟中介和购房者完成房屋购买过程。

 

程序代码

（1）Business—— 业务接口

package org.ccut.pack_2;

public interface Business {

    public static final double RATIO=0.022;

    public static final double TAX=0.03;

    void buying (double price);

}

 

 

（2）Buyer —— 购房者类

package org.ccut.pack_2;

public class Buyer implements Business{

    String name;

    public Buyer(String name) {
        this.name = name;
    }

    @Override
    public void buying(double price) {
        System.out.println(this.name+"购买了一套总价为"+price+"元的住宅。");
    }
}

 

 

（3）Intermediary—— 中介类

package org.ccut.pack_2;

public class Intermediary implements Business {

    Buyer buyer;

    public Intermediary(Buyer buyer) {
        this.buyer = buyer;
    }

    @Override
    public void buying(double price) {
        buyer.buying(price);
        charing(price);
    }

    public void charing(double price){
        System.out.println("中介公司收取的中介费用为："+(price*Business.RATIO)+"元。");
        System.out.println("需要交的契税为："+(price*Business.TAX)+"元。");
    }
}

 

 

（4）Test —— 主类

package org.ccut.pack_2;

import java.util.Scanner;

public class Test {
    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        Business business=new Intermediary(new Buyer("Lisa"));
        System.out.println("请输入要购买的房屋标价：");
        double price=scanner.nextDouble();
        business.buying(price);
    }
}

 

 

 

运行结果：

 

 

---

 

 

题目2：

输入5个数，代表学生成绩，计算其平均成绩。当输入值为负数或大于100时，通过自定义异常处理进行提示。

 

程序代码

 

（1）定义一个异常类NumberErrorException 用于处理输入值为负数或大于100时的错误

package org.ccut.pack_3;

public class NumberErrorException extends Exception {

    @Override
    public String toString() {
        return "输入值不能为负数或大于100";
    }

    @Override
    public String getMessage() {
        return super.getMessage();
    }

}

 

 

（2）主类Test

package org.ccut.pack_3;

import java.util.Scanner;

public class Test {
    public static void main(String[] args) {
        Scanner scanner=new Scanner(System.in);
        double sum=0.0;
        double score=0.0;
        try {
            for (int i = 0; i < 5; i++) {
                score=scanner.nextDouble();
                if(score<0||score>100)
                    throw new NumberErrorException();
                sum+=score;
            }
            System.out.println("平均成绩为："+sum/5);
        } catch (NumberErrorException e){
            System.out.println(e.toString());
        } catch (Exception e){
            System.out.println(e.getMessage());
        }
    }
}

 

 

运行结果

（1）正常输入时，

 

 

（2）输入负数时，

 

 （3）输入大于100的数时，