JAVA开发实战经典第六章课后习题答案.pdf

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) = 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 ; 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) - = name ; - -public void setSex(char sex) -this.sex = sex ; - -public void setAge(int age) -this.age = age ; - -public String getName() -return ; - -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 * th