[eNine]

here are two methods from a class that I wrote...these might be helpful. you'd still need to do a little work...

Code:

public boolean isPrime(long p){
	
	long pAsALong = p;
	long mySqrt = (long)Math.sqrt(pAsALong );
	long divisor = 3;
	if(p%2 == 2)
		return true;
	else if(p%2 == 0)
		return false;
	
	while(divisor <= mySqrt )
	{

		if(pAsALong % divisor == 0)
			return false;
		
		//only check odd numbers
		divisor+=2;
	}
	
return true;
}

//@return array list of longs that are prime factors
public ArrayList<Long> listPrimes(long upToWhat){
	ArrayList<Long> listOfPrimes = new ArrayList<Long>(20);
	listOfPrimes.add(2L);//add two

//only add odd numbers
for(long  potentialPrime = 3;potentialPrime<= upToWhat; potentialPrime+=2){
		if(isPrime(potentialPrime))
			listOfPrimes.add(potentialPrime);
	}
	return listOfPrimes ;
}