Hello, to be honest with you, your question is a bit unclear, at least to me.
Are you trying to give special skills to players based upon their weapon enchant level?
Also there are parts of the code that are wrong, for example you do:
if (item.getEnchantLevel() >= 4)
and then immediately after
else if (item.getEnchantLevel() >= 8)
This last block will never be evaluated since the previous one will be true, and so on.
From the snippets you posted I can't figure out, maybe try to post the whole files somewhere