That code doesn't tell you anything about what the query returns. In fact all it does is to run the query, ignore the data, and ask "What is the current row?"
And since you haven't tried to read anything from the query, the current row is naturally zero.
Any tutorial I have ever seen on
JDBC shows you how to read through a ResultSet using the rs.next() method. I would suggest you have a look at some JDBC tutorials.
(By the way: there is nothing special about servlets. So the fact that you have problems with JDBC code doesn't make this a servlets problem just because you happened to put the code in a servlet. I'm going to move the post to the JDBC forum, since it's a question about JDBC.)