java-继承类练习

阳光穿透心脏的1/2处 2024-04-01 13:40 66阅读 0赞

>     class TuXing

package com.dong;
    
    /**
     * @author Captain_Dong
     *
     * 这个类不能创建对象，原因：存在抽象方法，该方法无法工作
     * 如何才能使用？------>>>>进一步给出具体实现（到底是什么图形，我才能实现类）
     */
    public abstract class TuXing {
        private String mingCheng;
        public abstract double Area();
        public abstract double zhouChang();
        public String getAbc(){
            return "11111111111aaaaaaaaaaa222222222222bbbbbbbb!";
        }
    
        public TuXing() {
        }
    
        //public abstract String pp();
        public String pp(){  //一般方法的重写
            return "";
        }
        public TuXing(String mingCheng) {
            this.mingCheng = mingCheng;
        }
    
        public String getMingCheng() {
            return mingCheng;
        }
    
        public void setMingCheng(String mingCheng) {
            this.mingCheng = mingCheng;
        }
    
        @Override
        public String toString() {
            return "TuXing{" +
                    "mingCheng='" + mingCheng + '\'' +
                    '}';
        }
    }

>     public class JVXing

package com.dong;
    
    public class JVXing extends TuXing{
        //添加新属性
        private double x;//长
        private double y;//宽
    
        //构造方法
    
        public JVXing(String mingCheng, double x, double y) {
            super(mingCheng);
            this.x = x;
            this.y = y;
        }
        public JVXing( double x, double y) {
            super("矩形");//父类构造方法调用
            this.x = x;
            this.y = y;
        }
    
        @Override
        public double Area() {
            return this.x*this.y;
        }
    
        @Override
        public double zhouChang() {
            return 2*(this.y+this.x);
        }
    
        public String pp(){   //获取矩形相关信息
            //super.getAbc();
            String ss;
            ss=super.getAbc()+"\n"+super.getMingCheng()+"的长为："+this.x+",宽为："+this.y+"\n"+
                    "面积为："+this.Area()+",周长为："+this.zhouChang();
            return ss;
        }
    }

>     public class Circle

package com.dong;
    
    public class Circle extends TuXing{
    
        private  double r;
    
        public Circle(){
            super();
        }
        public Circle(String mingCheng, double r) {
            super(mingCheng);
            this.r = r;
        }
    
        public Circle(String s) {
        }
    
        @Override
        public double Area() {
           return Math.PI*Math.pow(this.r,2);
        }
    
        @Override
        public double zhouChang() {
            return 2*Math.PI*this.r;
        }
        public String pp(){
            String ss;
            ss="圆的面积为："+this.Area()+"周长为："+this.zhouChang();
            return ss;
        }
    
        public double getR() {
            return r;
        }
    
        public void setR(double r) {
            this.r = r;
        }
    }

>     public class Test01

package com.dong;
    
    public class Test01 {
        public static void main(String[] args) {
            JVXing jvXing2=new JVXing("矩形1",100,15);
    
            JVXing jvXing=new JVXing("第二个矩形",10,2);
            JVXing jvXing1=new JVXing(100,200);
    
            TuXing tuXing=new JVXing("矩形2",15,20);
            TuXing tuXing1=new JVXing("矩形3",15,30);
    
            System.out.println(tuXing.pp());
            System.out.println(tuXing1.pp());
    
            System.out.println(tuXing);
    
            Circle circle=new Circle("圆",100);
    
            TuXing tuXing2=new Circle("圆1"+100);
    
            System.out.println(tuXing1.pp());//调用的是矩形的方法（多态）自动识别对象的方法
            System.out.println(tuXing2.pp());//调用的是圆的方法（多态）
    
    
        }
    }