Constructor is not defined in java in eclipse though it is defined

Question

Help Please.... I am new in Java. I am trying to write a code that contains a class "point" into a public class "PeterAndSnowBlower" in Eclipse(Luna). I have also tried by making the variables x, y public in the class "point" and it gives the same error. I have also used this.x and this.y instead of x and y inside the constructors

Here is my code:

import java.util.*;
public class PeterAndSnowBlower {
    class point{
        int x;
        int y;
        public point() {
            x = y = 0;
        }
        public point(int a, int b){
            x = a;
            y = b;
        }
        public point(point p) {
            x = p.x;
            y = p.y;
        }
        public double distance(point P){
            int dx = x - P.x;
            int dy = y - P.y;
            return Math.sqrt(dx*dx + dy*dy);
        }
    }
    public static void main(String[] args){
        Scanner in = new Scanner(System.in);
        int n, x, y;
        point P = new point(0, 0);
        n = in.nextInt();
        P.x = in.nextInt();
        P.y = in.nextInt();
        Vector<point>points = new Vector<point>();
        for(int i = 0; i < n; i++){
            x = in.nextInt();
            y = in.nextInt();
            points.add(new point(x, y));
        }
        double r1, r2;
        r1 = r2 = P.distance(points.get(0));
        for(point point:points){
            r1 = Math.max(r1, P.distance(point));
        }

    }
}

the error is:

Multiple markers at this line
- No enclosing instance of type PeterAndSnowBlower is accessible. Must qualify the allocation with an enclosing instance of type PeterAndSnowBlower (e.g. 
 x.new A() where x is an instance of PeterAndSnowBlower).
- The constructor PeterAndSnowBlower.point(int, int) is undefined

don't create classes in classes. especially if you're new, start without an IDE to learn the basics. — Stultuske, Jan 21 '16 at 08:42
Make your `point` class `static` if you want a static access — Denys Séguret, Jan 21 '16 at 08:42

score 1 · Accepted Answer · edited Jan 21 '16 at 08:44

1

Unless the inner class is defined static, you cannot instantiate it from static method from outer class. The non-static class requires this reference to outer class.

Here it makes sense to declare this class as static. Obviously it doesn't refer to outer class.

edited Jan 21 '16 at 08:44

nitind

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answered Jan 21 '16 at 08:43

Zbynek Vyskovsky - kvr000

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should use `static class point`? – NAbdulla Jan 21 '16 at 08:45
thanks @kvr000, it is working. – NAbdulla Jan 21 '16 at 08:48

score 1 · Answer 2 · answered Jan 21 '16 at 08:45

You're statically accessing your inner class (meaning you don't do it from an instance of the outer class).

What you need is a static inner class, which makes perfect sense here as the inner class doesn't refer to the outer one.

Change the declaration to

static class point {

Constructor is not defined in java in eclipse though it is defined

2 Answers2