Laura,
It looks like one of those fields is being submitted empty. Do you have any validations?
Also, two pieces of advice:
1) It's considered bad practice to have
JDBC (or any
Java code really) in a JSP. Search for MVC to read more on this.
2) It's better to use a PreparedStatement rather than a Statement. The code is easier to read and you don't have to worry about SQL Injection.