Java++开发实战经典第六章课后习题答案

interface ClassName {

public String getClassName() ;

}

class Company implements ClassName{

private String className ;

public Company(){}

public Company(String className){

this.className = className ;

}

public String getClassName(){

return this.className ;

}

}

public class ExecDemo01{

public static void main(String args[]){

ClassName cn = new Company("Company类") ;

System.out.println(cn.getClassName()) ;

}

}

abstract class Shape{

public abstract float area() ;

}

class Triangle extends Shape{

private float foot ;

private float height ;

public Triangle(){}

public Triangle(float foot,float height){

this.setFoot(foot) ;

this.setHeight(height) ;

}

public float area(){

return this.foot * height / 2 ;

}

public void setFoot(float foot){

this.foot = foot ;

}

public void setHeight(float height){

this.height = height ;

}

public float getFoot(){

return this.foot ;

}

public float getHeight(){

return this.height ;

}

}

class Cycle extends Shape{

private float radius ;

private static final float PI = 3.1415926f ;

public Cycle(){}

public Cycle(float radius){

this.setRadius(radius) ;

}

public float area(){

return PI * this.radius * this.radius ;

}

public void setRadius(float radius){

this.radius = radius ;

}

public float getRadius(){

return this.radius ;

}

}

public class ExecDemo02{

public static void main(String args[]){

Shape s1 = new Triangle(30.0f,50.6f) ;

Shape s2 = new Cycle(25.3f) ;

System.out.println(s1.area()) ;

System.out.println(s2.area()) ;

}

}

abstract class Person{

private String name ;

private String addr ;

private char sex ;

private int age ;

public Person(){}

public Person(String name,String addr){

this(name,addr,'男',0) ;

}

public Person(String name,String addr,char sex,int age){ this.setName(name) ;

this.setAddr(addr) ;

this.setSex(sex) ;

this.setAge(age) ;

}

public abstract String getInfo() ;

public void setName(String name){

https://www.360docs.net/doc/ed16299308.html, = name ;

}

public void setAddr(String addr){

this.addr = addr ;

}

public void setSex(char sex){

this.sex = sex ;

}

public void setAge(int age){

this.age = age ;

}

public String getName(){

return https://www.360docs.net/doc/ed16299308.html, ;

}

public String getAddr(){

return this.addr ;

}

public char getSex(){

return this.sex ;

}

public int getAge(){

return this.age ;

}

}

class Student extends Person{

private float math ;

private float english ;

public Student(){}

public Student(String name,String addr){

super(name,addr) ;

}

public Student(String name,String addr,char sex,int age,float math,float english){ super(name,addr,sex,age) ;

this.setMath(math) ;

this.setEnglish(english) ;

}

public String getInfo(){

return "学生信息：" + "\n" +

"\t|- 姓名：" + super.getName() + "\n" +

"\t|- 年龄：" + super.getAge() + "\n" +

"\t|- 地址：" + super.getAddr() + "\n" +

"\t|- 性别：" + super.getSex() + "\n" +

"\t|- 数学成绩：" + this.getMath() + "\n" +

"\t|- 英语成绩：" + this.getEnglish() ;

public void setMath(float math){

this.math = math ;

}

public void setEnglish(float english){

this.english = english ;

}

public float getMath(){

return this.math ;

}

public float getEnglish(){

return this.english ;

}

}

public class ExecDemo03{

public static void main(String args[]){

Person per = new Student("张三","北极",'男',30,90.0f,90.0f) ;

System.out.println(per.getInfo()) ;

}

}

-- -- - --------------------------------------------------------------------------------------------------------------

-abstract class Employee{

- private String name ;

- private char sex ;

- private int age ;

- public Employee(){}

- public Employee(String name,char sex,int age){

-this.setName(name) ;

-this.setSex(sex) ;

-this.setAge(age) ;

- }

- public abstract String getInfo() ;

- public void setName(String name){

https://www.360docs.net/doc/ed16299308.html, = name ;

- }

- public void setSex(char sex){

-this.sex = sex ;

- }

- public void setAge(int age){

-this.age = age ;

- }

- public String getName(){

-return https://www.360docs.net/doc/ed16299308.html, ;

- public char getSex(){

-return this.sex ;

- }

- public int getAge(){

-return this.age ;

- }

-}

-

-class Manager extends Employee{

- private String job ;

- private float income ;

- public Manager(){}

- public Manager(String name,char sex,int age,String job,float income){ -super(name,sex,age) ;

-this.setJob(job) ;

-this.setIncome(income) ;

- }

- public void setJob(String job){

-this.job = job ;

- }

- public void setIncome(float income){

-this.income = income ;

- }

- public String getJob(){

-return this.job ;

- }

- public float getIncome(){

-return this.income ;

- }

- public String getInfo(){

-return "管理层信息：" + "\n" +

-"\t|- 姓名：" + super.getName() + "\n" +

-"\t|- 年龄：" + super.getAge() + "\n" +

-"\t|- 性别：" + super.getSex() + "\n" +

-"\t|- 职位：" + this.getJob() + "\n" +

-"\t|- 年薪：" + this.getIncome() ;

- }

-}

-class Worker extends Employee{

- private String dept ;

- private float salary ;

- public Worker(){}

- public Worker(String name,char sex,int age,String dept,float salary){

-super(name,sex,age) ;

-this.setDept(dept) ;

-this.setSalary(salary) ;

- }

- public String getInfo(){

-return "员工信息：" + "\n" +

-"\t|- 姓名：" + super.getName() + "\n" +

-"\t|- 年龄：" + super.getAge() + "\n" +

-"\t|- 性别：" + super.getSex() + "\n" +

-"\t|- 部门：" + this.getDept() + "\n" +

-"\t|- 月薪：" + this.getSalary() ;

- }

- public void setDept(String dept){

-this.dept = dept ;

- }

- public void setSalary(float salary){

-this.salary = salary ;

- }

- public String getDept(){

-return this.dept ;

- }

- public float getSalary(){

-return this.salary ;

- }

-}

-public class ExecDemo04{

- public static void main(String args[]){

-Employee m = new Manager("张三",'M',30,"技术主管",90.0f) ;

-Employee w = new Worker("李四",'F',19,"后勤",900.0f) ;

-System.out.println(m.getInfo()) ;

-System.out.println(w.getInfo()) ;

- }

-}

------------------------------------------------------------------------------------------------------------------ -abstract class Shape{

- public abstract float area() ;

- public abstract float perimeter() ;

-}

-class Triangle extends Shape{

- private float foot ;

- private float height ;

- public Triangle(){}

- public Triangle(float foot,float height){

-this.setFoot(foot) ;

-this.setHeight(height) ;

- }

- public float area(){

-return this.foot * height / 2 ;

- }

- public float perimeter(){

-return foot * 3 ;

- }

- public void setFoot(float foot){

-this.foot = foot ;

- }

- public void setHeight(float height){

-this.height = height ;

- }

- public float getFoot(){

-return this.foot ;

- }

- public float getHeight(){

-return this.height ;

- }

-}

-class Cycle extends Shape{

- private float radius ;

- private static final float PI = 3.1415926f ; - public Cycle(){}

- public Cycle(float radius){

-this.setRadius(radius) ;

- }

- public float area(){

-return PI * this.radius * this.radius ; - }

- public void setRadius(float radius){

-this.radius = radius ;

- }

- public float getRadius(){

-return this.radius ;

- }

- public float perimeter(){

-return PI * 2 * this.radius ;

- }

-}

-public class ExecDemo05{

- public static void main(String args[]){

-Shape s1 = new Triangle(30.0f,50.6f) ;

-Shape s2 = new Cycle(25.3f) ;

-System.out.println(s1.area()) ;

-System.out.println(s1.perimeter()) ;

-System.out.println(s2.area()) ;

-System.out.println(s2.perimeter()) ;

- }

-}

------------------------------------------------------------------------------------ -interface Goods{ // 商品

- public float getPrice() ;

- public String getName() ;

-}

-class ShopCar{ // 购物车

- private Goods goods[] ; // 保存商品

- private int foot ;

- public ShopCar(int len){

-if(len>0){

-this.goods = new Goods[len] ;

-}else{

-this.goods = new Goods[1] ; // 至少保持一个大小

-}

- }

- public void add(Goods goods){ // 向里面增加商品

-if(this.foot

-this.goods[this.foot++] = goods ; // 添加商品

-}

- }

- public float check(){

-float count = 0.0f ;

-for(int x=0;x

-if(this.goods[x]!=null){

-count += this.goods[x].getPrice() ;

-}

-}

-return count ;

- }

- public Goods[] getGoods(){

-return this.goods ;

- }

-}

-class Book implements Goods{

- private float price ;

- private String name ;

- public Book(float price,String name){

https://www.360docs.net/doc/ed16299308.html, = name ;

-this.price = price ;

- }

- public void setName(String name){

https://www.360docs.net/doc/ed16299308.html, = name ;

- }

- public void setPrice(float price){

-this.price = price ;

- }

- public String getName(){

-return https://www.360docs.net/doc/ed16299308.html, ;

- }

- public float getPrice(){

-return this.price ;

- }

-}

-public class ExecDemo06{

- public static void main(String args[]){

-ShopCar sc = new ShopCar(5) ;

-sc.add(new Book(79.8f,"Java开发")) ;

-sc.add(new Book(89.8f,"Java WEB 开发")) ;

-sc.add(new Book(99.8f,"Oracle 开发")) ;

-sc.add(new Book(39.8f,"HTML和网页制作")) ;

-for(int x=0;x

-if(sc.getGoods()[x]!=null){

-System.out.println(sc.getGoods()[x].getName() + " --> " + sc.getGoods()[x].getPrice()) ;

-}

-}

-System.out.println("结帐：" + sc.check()) ;

- }

-}