nested for the loop checker

here is my code Im kinda new to programming any way the goal of the program is to out put all the primes numbers between 0 and a user inputted value, each on their own line

import java.util.Scanner;
import java.math.*;

public class Sforprime{

  public static void main (String[] args){
    double box = 0;
    double boxxx = 0;
    int po = 0;
    int blub = 0;
    int no = 1;
    Scanner scan = new Scanner (System.in);
    System.out.println("input cieling number");
    box = scan.nextInt();
    boxxx = Math.sqrt(box);
    for (int batman = (int)box; batman >= 0; batman--){
      if (no == 1){
        no = 0;
      }
      else if (po == 0){
        System.out.println(blub);
        po = 0;
      }
      blub = batman;

      for (int mot = (int)boxxx; mot >= 2; mot--){
        if (po == 1 ){
        }
        else if (box%mot == 0){
          po++;
        }
      }
      if (po == 0){
        System.out.println(blub);
      }
    }
  }
}

What ends up happening is it doesn't do anything after you input the number. What am i doing wrong here?

Since you have initialised int mot = (int) boxxx box% mot will be 0 and po will always get incremented to 1 and hence never gets printed. Initialise mot=boxxx-1. But suggest you to use the above program as it is cleaner