Sieve of Eratosthenes Revisited, Java

Sieve of Eratosthenes Revisited

//'main' method must be in a class 'Rextester'.
//Compiler version 1.8.0_111

import java.util.*;
import java.lang.*;

class Rextester
{  
    private boolean vS[]=new boolean [1005];// instance variables are initialized to false 
    private int theSieve[] =new int [1005];//you can go crazy with these numbers 
    public void assign()
    {
        for (int i=1;i<=1000;i++)// the set of all natural numbers in the array
            theSieve[i]=i;
    }
    public void cancel()
    {
        for (int i=2;i<=1000;i++)
        {
            if (vS[i]==false)//if a current array index is false ie the index is prime then  <<<---- 
            {
                for (int j=2*i;j<=1000;j+=i)// all multiples of that index must be composite!!!!
                    vS[j]=true;
            }
        }
    }//end method cancel
    public void displaySieve()
    {
        for (int i=2;i<=1000;i++)
        {
            if (vS[i]==false)
                System.out.print(" "+theSieve[i]);
        }
    }
    public static void main (String args[])
    {
        Rextester sieve1=new Rextester();
        sieve1.assign();
        sieve1.cancel();
        sieve1.displaySieve();
    }
}//end class Rextester (Sieve of Eratosthenes)
//PS: vS mean virtual Sieve


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