package top.qaqaq.java.P268;

public class Circle {

	private double radius;// 半径

	public Circle() {
		radius = 1.0;
	}

	public double getRadius() {
		return radius;
	}

	public void setRadius(double radius) {
		this.radius = radius;
	}

	//返回圆的面积
	public double findArea() {
		return Math.PI * radius * radius;
	}

}

package top.qaqaq.java.P268;

public class Cylinder extends Circle {

	private double length;// 高

	public Cylinder() {
		length = 1.0;
	}

	public double getLength() {
		return length;
	}

	public void setLength(double length) {
		this.length = length;
	}

	//返回圆柱的体积
	public double findVolume() {
//		return Math.PI * getRadius() * getRadius() * getLength();
		return findArea() * getLength();
	}

}

package top.qaqaq.java.P268;

public class CylinderTest {

	public static void main(String[] args) {
		
		Cylinder cy = new Cylinder();
		
		cy.setRadius(2.1);
		cy.setLength(3.4);
		double volume = cy.findVolume();
		System.out.println("圆柱的体积为：" + volume);
		
		double area = cy.findArea();
		System.out.println("底面圆的面积：" + area);
	}
}