对象中—练习6

Circle.java

package com.atguigu.exer1;

public class Circle extends GeometricObject {

    private double radius;
    
    public Circle(double radius,String color, double weight) {
        super(color, weight);
        this.radius = radius;
    }

    public double getRadius() {
        return radius;
    }

    public void setRadius(double radius) {
        this.radius = radius;
    }
    
    public double findArea(){
        return 3.14 * radius * radius;
    }

}

GeometricObject.java

package com.atguigu.exer1;

public class GeometricObject {//几何图形

    protected String color;
    protected double weight;
    public String getColor() {
        return color;
    }
    public void setColor(String color) {
        this.color = color;
    }
    public double getWeight() {
        return weight;
    }
    public void setWeight(double weight) {
        this.weight = weight;
    }
    public GeometricObject(String color, double weight) {
        super();
        this.color = color;
        this.weight = weight;
    }
    
    public double findArea(){
        return 0.0;
    }
    
}

GeometricTest.java

package com.atguigu.exer1;
/*
 * 
 * 定义一个测试类GeometricTest，
 * 编写equalsArea方法测试两个对象的面积是否相等（注意方法的参数类型，利用动态绑定技术），
 * 编写displayGeometricObject方法显示对象的面积（注意方法的参数类型，利用动态绑定技术）。

 */
public class GeometricTest {

    public static void main(String[] args) {
        GeometricTest test = new GeometricTest();
        
        Circle c1 = new Circle(3.3, "white", 1.0);
        test.displayGeometricObject(c1);
        Circle c2 = new Circle(3.3, "white", 1.0);
        test.displayGeometricObject(c2);
        
        boolean isEquals = test.equalsArea(c1, c2);
        System.out.println("c1 和 c2的面积是否相等：" + isEquals);
        
        MyRectangle rect = new MyRectangle(2.1, 3.4, "red", 2.0);
        test.displayGeometricObject(rect);
        
    }
    
    public void displayGeometricObject(GeometricObject o){//GeometricObject o = new Circle(...)
        System.out.println("面积为：" + o.findArea());
    }
    
    //测试两个对象的面积是否相等
    public boolean equalsArea(GeometricObject o1,GeometricObject o2){
        return o1.findArea() == o2.findArea();
    }
}

MyRectangle.java

package com.atguigu.exer1;

public class MyRectangle extends GeometricObject {

    private double width;
    private double height;
    
    public MyRectangle(double width,double height,String color, double weight) {
        super(color, weight);
        this.width = width;
        this.height = height;
    }

    public double getWidth() {
        return width;
    }

    public void setWidth(double width) {
        this.width = width;
    }

    public double getHeight() {
        return height;
    }

    public void setHeight(double height) {
        this.height = height;
    }

    @Override
    public double findArea() {
        return width * height;
    }
}