实验四：Java继承与接口(bo)

实验四Java继承与接口【实验目的】理解继承原理与机制及类继承的声明方法掌握掌握成员变量的隐藏及方法的重写掌握抽象类与抽象方法4）掌握super关键字5）掌握final关键字6）理4掌握接口声明及使用【实验环境】JDK1.6+Eclpise3.2【实验准备】复习课件中理论知识练习课堂所讲的例子【实验内容】1Java3个类：People、ChinaPeople和AmericanPeople。该程序具体要求如下：PeoplepublicvoidspeakHello()publicvoidaverageHeight()和void方法。ChinaPeoplePeoplepublicvoidchinaGongfu()ChinaPeoplepublicvoidspeakHello()publicvoidaverageHeight()publicvoid方法。AmericanPeoplePeoplepublicvoidamericanBoxing()方法。要求AmericanPeople重写父类的publicvoidspeakHello()、publicaverageHeight()publicvoidaverageWeight()方法。TestOne输出信息。2、编写一个Java应用程序，除了主类（TestTwo）外，该程序还有Shape接口、三角形类Triangle类、矩形Rectangle类。该程序具体要求如下：ShapepublicabstractdoublecomputeArea(doublea,double抽象方法。TriangleShapea底、b代表三角形的高。RectangleShapea底、bTestTwo（要求使用到多态性）【实验过程及结果】实验代码及运行结果：packagefirst;publicclassTestfirst{publicstaticvoidmain(String[]args){Peoplepeople=newPeople();people.speakHello();people.averageHeigh();people.averageWeight();ewAmericanPeopleAmericanPeople();t(""chinapeople.speakHello();chinapeople.chinaGongfu();chinapeople.averageWeight();chinapeople.averageHeigh();t(""americanpeople.americanBoxing();americanpeople.speakHello();americanpeople.averageWeight();americanpeople.averageHeigh();}}packagefirst;publicclassAmericanPeopleextendsPeople{publicvoidamericanBoxing(){System.out.println("welikeboxing");}publicvoidspeakHello(){System.out.println("HELLO!!");}publicvoidaverageHeigh(){System.out.println("美国人的平均身高是170cm");}publicvoidaverageWeight(){System.out.println("美国人的平均体重是75kg");}}packagefirst;publicclassChinaPeopleextendsPeople{publicvoidchinaGongfu(){System.out.println("我们会少林寺功夫");}publicvoidspeakHello(){System.out.println("你好!!");}publicvoidaverageHeigh(){System.out.println("中国人的平均身高是167cm");}publicvoidaverageWeight(){System.out.println("中国人的平均体重是65kg");}}packagefirst;publicclassPeople{publicvoidspeakHello(){System.out.println("HELLO!!");}publicvoidaverageHeigh(){System.out.println("人的平均身高是00cm");}publicvoidaverageWeight(){System.out.println("人的平均体重是00kg");}}packagesecond;publicclassRectangleimplementsShape{publicdoublecomputeArea(doublea,doubleb){//doublek1=a*b;//doublek2=(a+b)*2;return(a*b);}}packagesecond;publicinterfaceShape{publicabstractdoublecomputeArea(doublea,doubleb);}packagesecond;publicclassTestsecond{publicstaticvoidmain(String[]args){ewdoubles1=puteArea(2.0,3.0);t("矩形的面积是："t( "ewdoubles2=puteArea(4.0,4.0);t("三角形的面积是："}}packagesecond