package examen2;

import java.io.*;
import java.util.*;

public class Examen2 {

    public static void main(String[] args) throws Exception {
        FileInputStream fis = new FileInputStream("dataIn.txt");
        BufferedReader br = new BufferedReader(new InputStreamReader(fis));

        TreeSet<Punct> set = new TreeSet();
        String line;

//problem in the while statement

        while (((line = br.readLine()).length() != 0)) {
            String[] splited = line.split("([^0-9\n\r\-][^0-9\n\r\-]*)");
            int[] number = new int[splited.length];

            for (int i=0, j=0; i<splited.length; i++) {
                number[j] = Integer.parseInt(splited[i]);
                j++;
            }

            set.add(new Punct(number[0], number[1]));

            Iterator it = set.iterator();

            while (it.hasNext()) {
                System.out.print(it.next());
            }
            System.out.println();
        }

        br.close();
        br = null;
        fis = null;
    }

    static class Punct implements Comparable {

        int x;
        int y;

        Punct() {
            x = 0;
            y = 0;
        }
        Punct(int x, int y) {
            this.x = x;
            this.y = y;
        }

         @Override
        public String toString() {
            return "(" + this.x + ":" + this.y + ")";
        }
        @Override
        public boolean equals(Object o) {
            try {
                Punct other = (Punct)o;
                return (this.x==other.x && this.y==other.y);
            } catch (Exception ex) {
                System.out.println(ex.getMessage());
            }
            return false;
        }
        @Override
        public int compareTo(Object t) {
            Punct other = (Punct)t;
            if (this.x == other.x  &&  this.y == other.y) {
                return 0;
            } else if (Math.sqrt(Math.pow(this.x, 2)+Math.pow(this.y, 2))-Math.sqrt(Math.pow(other.x, 2)+Math.pow(other.y, 2))>0) {
                return 1;
            } else {
                return -1;
            }
        }

        @Override
        public int hashCode() {
            return super.hashCode(); //To change body of generated methods, choose Tools | Templates.
        }
        @Override
        protected void finalize() throws Throwable {
            super.finalize(); //To change body of generated methods, choose Tools | Templates.
        }
        @Override
        protected Object clone() throws CloneNotSupportedException {
            return super.clone(); //To change body of generated methods, choose Tools | Templates.
        }

   }

}

at examen2.Examen2.main(Examen2.java:15)

while (((line = br.readLine()).length() != 0)) {

while((line=br.readLine())!=null) {
 //....
}

while (((line = br.readLine()).length() != 0)) {

while ((line = br.readLine() != null) {