Java编程用继承法实现圆锥、圆柱面积、体积

package baidu1206;
/**
* 求圆柱的表面积和体积
* @author Ming
*
*/
public class Column {
protected double P = 3.14159;
protected double r;//底面周长
protected double h;//高
/**
* 面积
* @return
*/
public double Area() {
return 2 * P * r * h + 2 * P * r * r;
}
/**
* 求体积
* @return
*/
public double Volume() {
return P * r * r * h;
}

public Column(double r, double h) {
super();
this.r = r;
this.h = h;
}
}
********************************************
package baidu1206;
/**
* 圆锥
* @author Ming
*
*/
public class Taper extends Column {
public Taper(double r, double h) {
super(r, h);

}

public double Area() {
return P * r * ((Math.sqrt(r * r + h * h)) + r);
}

public double Volume() {
return 1 / 3 * r * r * h;
}