java封裝private

package aaa;

class yuanzhuti {
	private float r;
	private float h;
	
	void setr(float a){
		if(a<0)
			System.out.println("數據不合法");
		else
		r=a;
	}
	
    void seth(float a){
		h=a;
	}
    
    float getr() {
    	return r;
    }
    
    float geth() {
    	return h;
    }
	
	void mj() {
		System.out.println("半徑為："+r+"的底面積："+3.14*r);
	}
	void tj() {
		System.out.println("半徑為："+r+"的體積："+3.14*r*h);
	}
}


public class test {

	public static void main(String[] args) {
		yuanzhuti y1=new yuanzhuti();
		y1.setr(-10.4f);
		y1.seth(20.5f);
		System.out.println(y1.getr());
		y1.mj();
		y1.tj();
		
		yuanzhuti y2=new yuanzhuti();
		y2.setr(12.4f);
		y2.seth(23.5f);
		y2.mj();
		y2.tj();
		
	}

}