Java-继承，多态练习0922-06

编写一个Shape类，具有属性：周长和面积；

定义其子类三角形和矩形，分别具有求周长的方法。

定义主类E，在其main方法中创建三角形和矩形类的对象，

并赋给Shape类的对象a、b，使用对象a、b来测试其特性。

父类：

package com.lianxi5;

//抽象类
public abstract class Shape {
    private double mianJi;
    private double zhouchang;
    public double getMianJi() {
        return mianJi;
    }
    public void setMianJi(double mianJi) {
        this.mianJi = mianJi;
    }
    public double getZhouchang() {
        return zhouchang;
    }
    public void setZhouchang(double zhouchang) {
        this.zhouchang = zhouchang;
    }

    public abstract double zhouchang();

}

子类;

package com.lianxi5;

public class Zc extends Shape {
    private double x;
    private double y;
    private double z;

    public double getX() {
        return x;
    }

    public void setX(double x) {
        this.x = x;
    }

    public double getY() {
        return y;
    }

    public void setY(double y) {
        this.y = y;
    }

    public double getZ() {
        return z;
    }

    public void setZ(double z) {
        this.z = z;
    }

    @Override
    public double zhouchang() {
        if((x+y)>z&&(x+z)>y&&(y+z)>x)
        {
            return x+y+z;
        }
        else
        {
        return 0;
        }

    }

}

package com.lianxi5;

public class Jxzc extends Shape {
    private double x;
    private double y;

    public double getX() {
        return x;
    }

    public void setX(double x) {
        this.x = x;
    }

    public double getY() {
        return y;
    }

    public void setY(double y) {
        this.y = y;
    }

    @Override
    public double zhouchang() {

        return (x+y)*2;
    }

}

测试;

package com.lianxi5;

public class Test {

    public static void main(String[] args) {
        Zc z=new Zc();
        Jxzc j=new Jxzc();
        z.setX(7);
        z.setY(8);
        z.setZ(9);
        System.out.println(z.zhouchang());

    }

}

结果：