Authenticating the username, password by using filters in Java (contacting with database)

Question

The following is the piece of Java code by using filters that shows the error page at every time if the username and password is also correct. Please help me, I don\'t have

Answer 1

First of all, you really should use parameterized queries for this. If the user enters '";DROP TABLE reg; as a username you will be in big trouble.

Also, are you sure the username and password are correct? How about capitalization?