Question

java初学，谁给找找错

class mypoint
{
private double x;
private double y;
mypoint()
{
double x=0;
double y=0;
}
mypoint(double x,double y)
{
this.x=x;
this.y=y;
}
void setx(double x)
{
this.x=x;
}
double getx()
{
return x;
}
void sety(double y)
{
this.y=y;
}
double gety()
{
return y;
}
static double distance(mypoint p1,mypoint p2)
{ double d=0;
d=Math.hypot((p1.getx()-p2.getx()),(p1.gety()-p2.gety()));
return d;
}
static double distance(mypoint p1)
{ double d=0;
d=Math.hypot((x-p1.getx()),(y-p1.gety()));
return d;
}
}
public class Mypoint1
{
public static void main(String args[])
{
mypoint r1=new mypoint();
mypoint r2=new mypoint();
static double x=0;
static double y=0;
r1.setx(3);
r1.sety(4);
r2.setx(7);
r2.sety(8);
System.out.println("(3,4)和(7,7)的距离为"+mypoint.distance(r1,r2));
System.out.println("(0,0)和（3,4）的距离为"+mypoint.distance(r1));

}

}

Answer 1

//注意，静态方法中，不能调用非静态成员变量

package com.ptengine;

class mypoint {
private double x;
private double y;

mypoint() {
double x = 0;
double y = 0;
}

mypoint(double x, double y) {
this.x = x;
this.y = y;
}

void setx(double x) {
this.x = x;
}

double getx() {
return x;
}

void sety(double y) {
this.y = y;
}

double gety() {
return y;
}

static double distance(mypoint p1, mypoint p2) {
double d = 0;
d = Math.hypot((p1.getx() - p2.getx()), (p1.gety() - p2.gety()));
return d;
}

static double distance(mypoint p1) {
double d = 0;
d = Math.hypot((0 - p1.getx()), (0 - p1.gety()));
return d;
}
}

public class Mypoint1 {
public static void main(String args[]) {
mypoint r1 = new mypoint();
mypoint r2 = new mypoint();
double x = 0;
double y = 0;
r1.setx(3);
r1.sety(4);
r2.setx(7);
r2.sety(8);
System.out.println("(3,4)和(7,7)的距离为" + mypoint.distance(r1, r2));
System.out.println("(0,0)和（3,4）的距离为" + mypoint.distance(r1));

}
}

追问

您可以给每个语句加个注释吗？刚开始学，实在是弄的我头晕

Answer 2

package zhidao;

class MyPoint
{
	double x;
	double y;

	public MyPoint ( double x, double y )
	{
		this.x = x;
		this.y = y;
	}

	double distance ( MyPoint p1, MyPoint p2 )
	{
		return Math.hypot (( p1.x - p2.x ), ( p1.y - p2.y ));
	}

	double distance ( MyPoint p1 )
	{
		return Math.hypot (( 0 - p1.x ), ( 0 - p1.y ));
	}
}

public class TestMyPoint
{
	public static void main ( String args[] )
	{
		MyPoint r1 = new MyPoint (3, 4);
		MyPoint r2 = new MyPoint (7, 8);
		System.out.println ("(3,4)和(7,7)的距离为" + r1.distance (r1, r2));
		System.out.println ("(0,0)和（3,4）的距离为" + r1.distance (r1));
	}
}