Java Find Prime Numbers

import java.util.*;
class PrimeNumbers{
public static void main (String args[]){
    Scanner input=new Scanner(System.in);
    System.out.print("Enter value of n: ");
    int n=input.nextInt();
    String primeNo = "";
    int j=0;
    System.out.println("Prime nums are:" );
    for (int i = 1; i < n; i++){ 
    for ( j = 2; j < i; j++){
    if (i % j == 0) {
    break;
    }
    }
    if (i == j) {
    primeNo += i + " ";
    }
}
System.out.println(primeNo);
}
}