testpoint.java

贬义的时候提示Point类型的p没有初始化

class Point {
		double x;
		double y;
		double z;
		
		Point(double _x, double _y, double _z){
			x = _x;
			y = _y;
			z = _z;
			}
			
	  void setX(double _x){
			x = _x;
			}
			
	  void setY(double _y){
			y = _y;
			}
			
		void setZ(double _z){
			z = _z;
			}
			
	  double getDistance(Point p){
			return (x - p.x)*(x - p.x) + (y - p.y)*(y - p.y) + (z - p.z)*(z - p.z);	
			}
		}	
		
	public class TestPoint{
		public static void main(String[] args){
			Point p;
			Point P = new Point(1.0,2.0,3.0);
			Point p1 = new Point(0.0,0.0,0.0);
			System.out.println(p.getDistance(p1));
			p.setX(5.0);
			System.out.println(p.getDistance(new Point(1.0,1.0,1.0)));
			}
		}