Java Generating Prime Number

/*
This class check the prime number between 1 to 1000 and write the prime number.
*/
public class PrimeNumber
{
// This method tests whether a given number is prime or not.
public static boolean isPrime ( int num )
{
boolean prime = true;
int limit = (int) Math.sqrt ( num );
for ( int i = 2; i <= limit; i++ )
{
if [...]