Sieve Coding Not Pairing In Output

When I compile the code, it goes through fine in the compiler. However after entering the boundaries for the lower an upper it doesn't produce the prime pairs between the two boundaries that the user sets. I have tried changing some of my integers that i initialized no luck. I looked at the last section of public void showPrimes() . However I can't seem to see where it has gone wrong there. I have included the entire code, plus the section again that I think is wrong. I have also posted the final output of what it looks like and what else should be included to make it easier to see what I am missing. Basically it keeps giving me zero primes even when the boundary is 100 and 200, or so and so forth.

import java.util.Scanner;
public class kbeaudry_xSieve
{
public static void main (String args[]){
kbeaudry_xSieve i = new kbeaudry_xSieve();
}
boolean primes[] = new boolean [50001];
int upper;
int lower;

[code]....

This is what i get when I actually run the program. However in the section where I have added *****, this is where it should put the prime pairs in.

Please enter a lower boundary and an upper boundary and I will print all of the sexy prime pairs between those boundaries.
Please enter the lower boundary (between 1 and 50000): 200
Please enter the upper boundary (between 1 and 50000): 600

There were 0 sexy pairs displayed between 200 and 600.. I am still working on another code for my that I had issues with, however I had to go out of the country for a few days to take care of some work.