This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
If the limit is negative, the actual value doesn't matter. The negative value just means to split into as many tokens as possible, and preserve any trailing empty tokens.
In this one, the first empty string is between the first two "o"s, the second empty string is between the other two "o"s, and that last empty string is there because the target ends with a delimiter, and the empty string is "after" that.