package com.b;public class Ponit {	private double x;	private double y;	private double z;	public Ponit() {	}	public Ponit(double a, double b, double c) {		x = a;		y = b;		z = c;	}	public double getX() {		return x;	}	public void setX(double a) {		x = a;	}	public double getY() {		return y;	}	public void setY(double b) {		y = b;	}	public double getZ() {		return z;	}	public void setZ(double c) {		z = c;	}	public void count1(Ponit s) {		double m = Math.sqrt((x - s.x) * (x - s.x) + (y - s.y) * (y - s.y)				+ (z - s.z) * (z - s.z));		System.out.println("两点的距离：" + m);	}	public void count2() {		double ss = Math.sqrt(x * x + y * y + z * z);		System.out.println("点到原点的距离：" + ss);	}	public void print() {		System.out.println("点的x坐标：" + x + "点的y坐标：" + y + "点的z坐标：" + z);	}}

　　测试类：

package com.b;public class Eye {	public static void main(String[] args) {		Ponit p = new Ponit(1, 4, 2);		Ponit p2 = new Ponit(2, 4, 1);		p.count1(p2);		p2.count2();		p.print();	}}

　　总结：难以下手的是：那个求两点间的距离，因为是三维空间，所以并不是需要把每一个坐标x,y,z都声明，有get方法，还有就是公式。自己对方法的理解还有很大缺陷。若有更好的方法，欢迎reply