公共方法访问私有成员变量

package demo1package;

public class Cylinder {
	private double radius;
	private double pi;
	
	public void setnumber(double r,double p){//公共方法用于对私有成员进行访问
		if(r>0 && p>0){
			radius=r;
			pi=p;
		}else
			System.out.println("您的输入有误");
	}
	
	double area(){
		return pi*radius*radius;
	}
	
	
}

　　

package demo1package;

public class text1 {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Cylinder cylinder=new Cylinder();
		
		cylinder.setnumber(3,3.14);
		
		System.out.println("圆的面积是："+cylinder.area());
		
		
	}

}