JAVA语言程序设计（基础篇） 第十版——第11章 继承和多态 （参考答案）

编程练习题

（11.2~11.4节）+（11.5~11.14节）

11.1（三角形Triangle）

父类（左边） 和   子类（右边）继承关系，

如下图： 

package p11;public class GeometricObject {private String color = "white";private boolean filled;private java.util.Date dateCreated;public GeometricObject() {dateCreated=new java.util.Date();}public GeometricObject(String color, boolean filled) {dateCreated=new java.util.Date();this.color=color;this.filled=filled;}public String getColor() {return color;}public void setColor(String color) {this.color=color;}public boolean isFilled() {return filled;}public void setFilled(boolean filled) {this.filled=filled;}public java.util.Date getDateCreated() {return dateCreated;}public String toString() {return "created on " + dateCreated + "\ncolor: " + color+   " and filled: " + filled;}
}

package p11;public class Triangle extends GeometricObject {private double side1 = 1.0;private double side2 = 1.0;private double side3 = 1.0;public Triangle() {}//这是一个 重载 的构造方法public Triangle(double side1, double side2,double side3, String color, boolean filled) {   super(color,filled);//或者 调用父类中已有方法 ,如下//setColor(color);//setFilled(filled);this.side1=side1;this.side2=side2;this.side3=side3;}public double getSide1() {return side1;}public double getSide2() {return side2;}public double getSide3() {return side3;}public double getArea() {double s=(side1+side2+side3)/2;double area=Math.pow( s*(s-side1)*(s-side2)*(s-side3) , 0.5); return area;}public double getPerimeter() {return side1+side2+side3;}@Overridepublic String toString() {return super.toString() + "\nArea is " + getArea();}
}

package p11;import java.util.Scanner;public class Test1 {public static void main(String[] args) {Scanner input=new Scanner(System.in);System.out.print("请输入三角形的三条边：");double s1=input.nextInt();double s2=input.nextInt();double s3=input.nextInt();System.out.print("请输入三角形的颜色: ");String c1=input.next();System.out.print("请输入一个boolean值(false:不填充；true：填充)：");   boolean f1=input.nextBoolean();input.close();//创建对象GeometricObject object=new Triangle(s1, s2, s3, c1, f1);System.out.println(object.toString());}}

（11.5~11.14节）

11.2（Person、Student、Employee、Faculty 和 Staff类）

这个不难，我也就是在 受聘日期 那里“卡壳”了一下

总体的继承关系：

package p11;public class Person {private String name;private String adress;private String phone;private String email;public Person(String name, String adress, String phone, String email) {this.name=name;this.adress=adress;this.phone=phone;this.email=email;}public Person(String name) {this.name=name;}public String getAdress() {return adress;}public void setAdress(String adress) {this.adress=adress;}public String getPhone() {return phone;}public void setPhone(String phone) {this.phone=phone;}public String getEmail() {return email;}public void setEmail(String email) {this.email=email;}public String toString() {return "The Person's name is "+name+"\nAdress is "+adress+"\nPhone is "+phone+"\nEmail is "+email;}
}

package p11;public class Student extends Person {private int classState;public final static int FRESHMAN=1;//大一新生public final static int SOPHOMORE=2;//大二学生public final static int JUNIOR=3;//大三学生public final static int SENIOR=4;//大四学生public Student(int classState, String name, String adress, String phone, String email) {super(name, adress, phone, email);this.classState=classState;}public int getClassState() {return classState;}public void setClassState(int classState) {this.classState=classState;}@Overridepublic String toString() {return "The Student's classState is "+classState+"\n"+super.toString();}
}

package p11;import java.util.Date;import p10.MyDate;public class Employee extends Person {private String office;private double salary;private MyDate DateOfAppointment;//受聘日期//构造方法public Employee(String office, double salary, MyDate DateOfAppointment, String name, String adress, String phone, String email) {super(name, adress, phone, email);this.DateOfAppointment=DateOfAppointment;this.salary=salary;this.office=office;}public String getOffice() {return office;}public void setOffice(String office) {this.office=office;}public double getSalary() {return salary;}public void setSalary(double salary) {this.salary=salary;}public String getDateOfAppointment() {return DateOfAppointment.getYear()+"年"+DateOfAppointment.getMonth()+"月"+DateOfAppointment.getDay()+"日";}@Overridepublic String toString() {return "The Employee's dateOfAppointment is "+  getDateOfAppointment()+"\nOffice is "+office+"\nSalary is "+salary+"\n"+super.toString();}
}

package p11;import p10.MyDate;public class Faculty extends Employee {private long officeHours;private String rank

本文来自互联网用户投稿，文章观点仅代表作者本人，不代表本站立场，不承担相关法律责任。如若转载，请注明出处。 如若内容造成侵权/违法违规/事实不符，请点击【内容举报】进行投诉反馈！