JAVA实验6答案

1、GDOU-B-11-112广东海洋大学学生实验报告书（学生用表）实验名称 实验六 Java的接口与实现 课程名称JaVa程序设计与开发 课程号16232204技术学院（系）学生姓名信息学院专业学号计算机科学与技术班级计科实验地点钟海楼04019实验日期2015 年10月26日、实验目的（1）学习掌握Java中类怎样实现接口、接口回调技术;（2）学习掌握Java程序中面向接口的编程思想。二、实验任务完成实验六指导上实验1、实验2、实验3的实验任务三、实验仪器设备和材料安装有J2SE开发工具的PC机。四、实验内容和步骤实验1代码如下：Estimator.javain terface Compure

2、rAveragepublic double average(double x);class Gymn astics impleme nts CompurerAverage public double average(double x) int coun t=x .len gth;double aver=0,temp=0;for(int i=0;i<count;i+) for(i nt j=i;j<co un t;j+) if(xj<xi) temp=xj; xj=xi; xi=temp;for(i nt i=1;i<co un t-1;i+)aver=aver+xi;i

3、f(cou nt>2)aver=aver/(co un t-2);elseaver=0;retur n aver;class School impleme nts CompurerAveragepublic double average(double x)int coun t=x .len gth;double sum=0;for(int i=0;i<count;i+)sum+=xi;retur n sum/co unt;public class Estimatorpublic static void main( Stri ng args)double a=9.89,9.88,9.

4、99,9.12,9.69,9.76,8.97;double b=89,56,78,90,100,77,56,45,36,79,98;CompurerAverage computer;computer =new Gymn astics();double result=computer.average(a);System.out.pri ntf("% n");System.out.pri ntf("体操选手最后得分：%5.3fn",result);computer =new School();result=computer.average(b);System

5、.out.pri ntf("班级考试平均分数：%-5.2fn",result);运行结果：9. 66873. 09练习：JAVACEstimator.java:27:错误：School不是抽象的,并且未覆盖 CompurerAverage中的抽象方法 average(double)class School impleme nts CompurerAverageA1个错误实验2代码如下：CheckCarWeight.javain terface ComputerWeightpublic double computerWeight();class Televisi on imp

6、leme nts ComputerWeightpublic double computerWeight()return 10.0;class Computer impleme nts ComputerWeightpublic double computerWeight()return 8.0;class WashMach ine impleme nts ComputerWeightpublic double computerWeight()return 35.5;class TruckComputerWeight goods;double totalWeihts=0;Truck(Compute

7、rWeight goods)this.goods=goods;public void setGoods(ComputerWeight goods)this.goods=goods;public double getTotalWeigths()totalWeihts=0;for(int i=0;i<goods.length;i+)totalWeihts+=puterWeight();return totalWeihts;public class CheckCarWeightpublic static void main( Stri ng args)ComputerWei

8、ght goods=new ComputerWeight650; for(int i=0;i<goods.length;i+)if(i%3=0)goodsi=new Televisi on();if(i%3=1)goodsi=new Computer。；if(i%3=2)goodsi=new WashMachi ne();Truck truck=new Truck(goods);System.out.pri ntf("n货车装载的货物重量：%-8.5f kgn",truck.getTotalWeigths();goods=new ComputerWeight68;fo

9、r(int i=0;i<goods.length;i+)if(i%2=0)goodsi=new Televisi on();elsegoodsi=new WashMachi ne();truck.setGoods(goods);System.out.pri ntf("货车装载的货物重量：%-8.5f kgn",truck.getTotalWeigths();运行结果：货车装载的货物重量：11574- 00000 kg 货车装载的货物重量：1547. 00000 kg 请按任意键继续*练习：class Refrigerrator impleme nts Computer

10、Weight public double computerWeight()return 10.5;不需修改Truck类实验3代码如下：CheckDogState.javain terface DogStatepublic void showState();class SoftlyState impleme nts DogStatepublic void showState()System.out.println(”听主人的命令");class MeetE nemyState impleme nts DogStatepublic void showState()System.out.p

11、rintln(”狂叫，并冲向去狠咬敌人");class MeetFrie ndState impleme nts DogStatepublic void showState()System.out.println(”晃动尾巴，表示欢迎");class MeetA no therDog impleme nts DogStatepublic void showState() System.out.pri ntl n(" 嬉戏");class DogDogState state;public void show()state.showState();publi

12、c void setState(DogState s) state=s;public class CheckDogStatepublic static void main( Stri ng args)Dog yellowDog=new Dog();System.out.pri nt("狗在主人面前："); yellowDog.setState( new SoftlyStateO);yellowDog.show();System.out.pri nt("狗遇到敌人："); yellowDog.setState( new MeetE nemyState();

13、 yellowDog.show();System.out.pri nt("狗遇到朋友："); yellowDog.setState(new MeetFriendState(); yellowDog.show();System.out.pri nt("狗遇到同伴："); yellowDog.setState(new MeetAnotherDog(); yellowDog.show();运行结果:狗在主人面前：听主人的命令狗遇到敌人：狂叫，并冲向去狠咬敌人狗遇到朋友：晃动尾巴，表示欢迎 狗遇到同伴；嬉戏请按任意键继续练习：CheckWaterState.ja

14、vain terface WaterStatepublic void showState();class ColdState impleme nts WaterState public void showState()System.out.pri ntl n("固态");class Ordin aryState impleme nts WaterState public void showState()System.out.pri ntl n("液态");class HotState impleme nts WaterState public void

15、showState()System.out.pri ntl n("气态");class WaterWaterState state;public void show()state.showState();public void setState(WaterState s) state=s;public class CheckWaterStatepublic static void main( Stri ng args)Water water =new Water();System.out.print(" 低于 0° C:"); water.setState(new ColdState(); water.show();System.out.print(" 高于 0° C且低于 100° C:&