【Java】实验三

1、按照要求使用Java进行编码。

1) 编写一个抽象类Shape，其中有抽象方法getArea（）和getPerimeter（）

2) 在Shape类的基础上派生出Rectangle和Circle类，二者都实现了计算面积的方法getArea（）和计算周长的方法getPerimeter（）；

3) 构造main函数，生成Rectangle和Circle对象，并用Shape类型的变量调用Rectangle和Circle对象的getArea（）和getPerim（）方法。 

package com.ly.shape;

abstract class Shape {
    public abstract double getArea();
    public abstract double getPerimeter();
}

package com.ly.shape;

public class Rectangle extends Shape{
    private double x,y;
    Rectangle(double x,double y){
        this.x=x;
        this.y=y;
    }
    public double getX(){
        return x;
    }
    public double getY(){
        return y;
    }
    public double getArea() {
        return getX()*getY();
    }
    public double getPerimeter() {
        return 2*(x+y);
    }
}

package com.ly.shape;

public class Circle extends Shape{
    double PI=3.1415926;
    double r;
    Circle(double r){
        this.r=r;
    }
    double getRadius(){
        return r;
    }
    public double getArea() {
        return PI*getRadius()*getRadius();
    }
    public double getPerimeter() {
        return 2*PI*getRadius();
    }
}

package com.ly.shape;

public class main {
    public static void main(String[] args) {
        Shape rec = new Rectangle(4.0,5.0);
        Shape cr = new Circle(3.0);
        
        System.out.println("矩形面积："+rec.getArea());
        System.out.println("矩形周长："+rec.getPerimeter());
        
        System.out.println("圆形面积："+cr.getArea());
        System.out.println("圆形周长："+cr.getPerimeter());
    }
}

 

2、以电话为父类，移动电话和固定电话为两个子类，并使移动电话实现接口：可移动。固定电话又有子类：无绳电话。定义接口及各类，明确他们的继承关系。

package com.ly.phone;

public class settlementPhone implements Phone{
    public settlementPhone(){}
    public void move(){
        System.out.println("固定电话"+NOMOVE);
    }
}

package com.ly.phone;

public class mobilePhone implements Phone{
    public mobilePhone(){}
    public void move(){
        System.out.println("移动电话"+MOVE);
    }
}

package com.ly.phone;

public class silentPhone extends settlementPhone{
    public silentPhone(){}
    public void move(){
        System.out.println("无绳电话"+NOMOVE);
    }
}

package com.ly.phone;

public class main {
    public static void main(String[] args) {
        Phone phone1 = new mobilePhone();
        phone1.move();
        
        Phone phone2 = new settlementPhone();
        phone2.move();
        
        Phone phone3 = new silentPhone();
        phone3.move();
    }

}

 

3、在实验2中所实现的Teacher类的基础上，修改Teacher类的代码，要求：由多个Teacher对象所形成的数组可以使用Arrays.sort方法进行排序（编号由低到高排序）。

package com.ly.teacher;

public class Teacher implements Comparable{
    private int no;
    private String name;
    private int age;
    private String seminary;
    
    Teacher(int no,String name,int age,String seminary){
        this.no = no;
        this.name = name;
        this.age = age;
        this.seminary = seminary;
    }
    public int getNo(){
        return no;
    }
    public String getName(){
        return name;
    }
    public int getAge(){
        return age;
    }
    public String getSeminary(){
        return seminary;
    }
    public void setNo(int no){
        this.no = no;
    }
    public void setName(String name){
        this.name = name;
    }
    public void setAge(int age){
        this.age = age;
    }
    public void setSeminary(String seminary){
        this.seminary = seminary;
    }
    
    public boolean equal(Object o){
        boolean result=false;
        Teacher t = (Teacher)o;
        if(this.no==t.no){
            return true;
        }
        return result;
    }
    public String toString(){
        return "编号："+no+"\n"
                +"姓名："+name+"\n"
                +"年龄："+age+"\n"
                +"学院："+seminary+"\n";
    }
    
    //实现接口Comparable
    public int compareTo(Object o) {
        Teacher otherTea = (Teacher)o;
        if(no<otherTea.no) return -1;
        if(no>otherTea.no) return 1;
        return 0;
    }
}

package com.ly.teacher;

import java.util.Arrays;

public class main {
    public static void main(String[] args) {
        Teacher[] TeaArray = new Teacher[3];
        TeaArray[0] = new Teacher(1002,"Blanche",20,"College of information and science engineering");
        TeaArray[1] = new Teacher(1001,"David",21,"College of information and science engineering");
        TeaArray[2] = new Teacher(1003,"Kate",22,"College of information and science engineering");
        
        Arrays.sort(TeaArray);
        for(int i=0;i<TeaArray.length;i++){
            System.out.print(TeaArray[i].getNo()+ ":");
            System.out.println(TeaArray[i].getName());
        }
    }
}