java继承作业.doc

1假设A是一个类。那么举例说明new A和A a=new A()的区别。最好是说出原理堆里面对象的首地址给栈里的变量，如果只操作变量的话，不会导致对象的地址改动，从而可以多次使用，而匿名对象只能直接操作对象，每new一次又重新开辟一块内存空间，产生新的对象package com.wepull.extendS.test;public class Test01 public static void main(String args) System.out.println(new A(); System.out.println(new A(); /匿名对象 只能用一次 A a=new A();System.out.println(a);System.out.println(a);/可以多次使用class A2完成：动物园的饲养员为猫吃鱼，狗吃肉，大象吃香蕉.package com.wepull.extendS.test;public class Test02 public static void main(String args) Person a=new Person();Animal a1=new Cat(猫);Animal a2=new Dog(狗);Animal a3=new Elephant(大象);Food f1=new Food(鱼);Food f2=new Food(肉);Food f3=new Food(香蕉);a.feed(a1, f1);a.feed(a2, f2);a.feed(a3, f3);class Animalprivate String name;public Animal(String name) = name;void eat(Food f)System.out.println(name+吃+f.getName();class Cat extends Animalpublic Cat(String name)super(name);class Dog extends Animalpublic Dog(String name)super(name);class Elephant extends Animalpublic Elephant(String name)super(name);class Foodprivate String name;public String getName() return name;public void setName(String name) = name;public Food(String name) = name;class Personvoid feed(Animal a,Food d)a.eat(d);3有农民,教师,科学家,服务生,其中农民,服务生只有基本工资.教师除基本工资外,还有课酬(元/天),科学家除基本工资外,还有年终奖,请你写出相关类,将各种类型的员工的全年工资打印出来。package com.wepull.extendS.test;public class Test03 public static void main(String args) Employee a=new Peasant(农民,3000);Employee b=new Teacher(教师,4000,100);Employee c=new Scientist(科学家,10000,50000);Employee d=new Peasant(服务生,3001);a.SAL();b.SAL();c.SAL();d.SAL();class Employeepublic String name;public double sal;void SAL()public Employee(String name, double sal) super(); = name;this.sal = sal;class Peasant extends Employeepublic Peasant(String name,double sal)super(name,sal);void SAL()System.out.println(name+的年薪为：+sal*12);class Teacher extends Employeepublic double forclass;public Teacher(String name, double sal, double forclass) super(name, sal);this.forclass=forclass;void SAL()double m=sal*12+forclass*100;System.out.println(name+的年薪为：+m);class Scientist extends Employeepublic double yearaward;public Scientist(String name, double sal,double yearaward) super(name, sal);this.yearaward=yearaward;void SAL()double m=sal*12+yearaward;System.out.println(name+的年薪为：+m); class Waiter extends Employeepublic Waiter(String name, double sal) super(name, sal);void SAL()System.out.println(name+的年薪为：+sal*12);4.在一次答辩的比赛中,一共有10个题目,假设最开始的时候，每个选手都有10分,每个选手必须答完，每道题,要是答对了当前的分数是原来的两倍。要是答错了，当前的分数减去当前的题号。假设答对了该题目显示的是1，错的是0，若一个选手得到的分数是100.那么可以求出这个选手答对