[zoe]

Problem is here..

Code:

DbUserName=rs.getString(username);
DbPassword = rs.getString(password);
replace it with
DbUserName=rs.getString(1);
DbPassword = rs.getString(2);
Or
DbUserName=rs.getString("DbUserName");
DbPassword = rs.getString("DbPassword");

The code should be actually

Code:

String username = request.getParameter("username");
String password = request.getParameter("password");

while(rs.next()) {
DbUserName=rs.getString(1);
DbPassword = rs.getString(2);
if (username.equals(DbUserName) && password.equals(DbPassword)) {

}
else {

}

}