JAVA实验答案

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程序设计与开发技术课程号16232204学院(系)信息学院专业计算机科学与技术班级计科学生姓名学号实验地点钟海楼04019实验日期2015年10月26日一、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.javainterface Compure

2、rAveragepublic double average(double x);class Gymnastics implements CompurerAveragepublic double average(double x)int count=x.length;double aver=0,temp=0;for(int i=0;i<count;i+)for(int j=i;j<count;j+)if(xj<xi)temp=xj;xj=xi;xi=temp;for(int i=1;i<count-1;i+)aver=aver+xi;if(count>2)aver=

3、aver/(count-2);else aver=0;return aver;class School implements CompurerAveragepublic double average(double x)int count=x.length;double sum=0;for(int i=0;i<count;i+)sum+=xi;return sum/count;public class Estimatorpublic static void main(String args)double a=9.89,9.88,9.99,9.12,9.69,9.76,8.97;double

4、 b=89,56,78,90,100,77,56,45,36,79,98;CompurerAverage computer;computer=new Gymnastics();double result=computer.average(a);System.out.printf("%n");System.out.printf("体操选手最后得分：%5.3fn",result);computer=new School();result=computer.average(b);System.out.printf("班级考试平均分数：%-5.2fn&

5、quot;,result);运行结果：练习：- JAVAC -Estimator.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 implements CompurerAverage1 个错误实验2代码如下：CheckCarWeight.javainterface ComputerWeightpublic double computerWeight();class Television implements ComputerWeightpublic double computerWe

6、ight()return 10.0;class Computer implements ComputerWeightpublic double computerWeight()return 8.0;class WashMachine implements ComputerWeightpublic double computerWeight()return 35.5;class TruckComputerWeight goods;double totalWeihts=0;Truck(ComputerWeight goods)this.goods=goods;public void setGood

7、s(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(String args)ComputerWeight goods=new ComputerWeight650;for(int i=0;i<goo

8、ds.length;i+)if(i%3=0)goodsi=new Television();if(i%3=1)goodsi=new Computer();if(i%3=2)goodsi=new WashMachine();Truck truck=new Truck(goods);System.out.printf("n货车装载的货物重量：%-8.5f kgn",truck.getTotalWeigths();goods=new ComputerWeight68;for(int i=0;i<goods.length;i+)if(i%2=0)goodsi=new Tele

9、vision();elsegoodsi=new WashMachine();truck.setGoods(goods);System.out.printf("货车装载的货物重量：%-8.5f kgn",truck.getTotalWeigths();运行结果：练习：class Refrigerrator implements ComputerWeightpublic double computerWeight()return 10.5;不需修改Truck类实验3代码如下：CheckDogState.javainterface DogStatepublic void show

10、State();class SoftlyState implements DogStatepublic void showState()System.out.println("听主人的命令");class MeetEnemyState implements DogStatepublic void showState()System.out.println("狂叫，并冲向去狠咬敌人");class MeetFriendState implements DogStatepublic void showState()System.out.println(&qu

11、ot;晃动尾巴，表示欢迎");class MeetAnotherDog implements DogStatepublic void showState()System.out.println("嬉戏");class DogDogState state;public void show()state.showState();public void setState(DogState s)state=s;public class CheckDogStatepublic static void main(String args)Dog yellowDog=new Do

12、g();System.out.print("狗在主人面前：");yellowDog.setState(new SoftlyState();yellowDog.show();System.out.print("狗遇到敌人：");yellowDog.setState(new MeetEnemyState();yellowDog.show();System.out.print("狗遇到朋友：");yellowDog.setState(new MeetFriendState();yellowDog.show();System.out.prin

13、t("狗遇到同伴：");yellowDog.setState(new MeetAnotherDog();yellowDog.show();运行结果：练习：CheckWaterState.javainterface WaterStatepublic void showState();class ColdState implements WaterStatepublic void showState()System.out.println("固态");class OrdinaryState implements WaterStatepublic void s

14、howState()System.out.println("液态");class HotState implements WaterStatepublic void showState()System.out.println("气态");class WaterWaterState state;public void show()state.showState();public void setState(WaterState s)state=s;public class CheckWaterStatepublic static void main(String args)Water water=new Water();System.out.print("低于0°C：");water.setState(new ColdState();water.show();Syste