Prime numbers - code problem

[Clive van Hilten]

Hi there - can anyone tell me why this will not compile?
======================================================
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import java.io.*;
import java.math.*;

//generates a prime of approx. 50 digits
public class SimplePrimeTag extends TagSupport
{
protected int len = 50;
public int doStartTag()
{
try
{
JspWriter out = pageContext.getOut();
BigInteger prime = Primes.nextPrime(Primes.random(len));
out.print(prime);
}
catch (IOException ioe)
{
System.out.println("Error generating prime: " + ioe);
}
return (SKIP_BODY);
}
}
============================================================
Error message reads:
E:\Program Files\Apache Group\Tomcat2\webapps\examples\WEB-INF\classes\coreservlets\tags\SimplePrimeTag.java:20: cannot resolve symbol
symbol : variable Primes
location: class SimplePrimeTag
BigInteger prime = Primes.nextPrime(Primes.random(len));
^
E:\Program Files\Apache Group\Tomcat2\webapps\examples\WEB-INF\classes\coreservlets\tags\SimplePrimeTag.java:20: cannot resolve symbol
symbol : variable Primes
location: class SimplePrimeTag
BigInteger prime = Primes.nextPrime(Primes.random(len));
^
2 errors
==============================================================
I copied this straight from a Sun custom jsp tags tutorial.
Thank you.
Clive

[Cindy Glass]

It looks like it can't find the class Primes, so it thinks that it is a variable that you forgot to declare and instantiate.

[Clive van Hilten]

Thanks Cindy. Where is the class Primes to be found? I would have thought it was covered by 'import java.math.*'?

[Roy Tock]

Being a mathematician, I'm VERY interested to see this Primes class. I'd even be more interested in seeing the source.