Hi all,
I have some questions for you. I cannot specifically point out what kind of problem I am encountering in my application, but here's what's happening:
- I have a web application project deployed in the Sun Glassfish Sever, the project follows the MVC2 architecture.
- I am using connection pool for database connection.
- I have an OracleDAOFactory with one method getConnection() which gets a DataSource object from the connection pool.
- I have a SuperDAO which creates a Connection object by calling the getConnection() method in the OracleDAOFactory. This call to getConnection() is in its constructor.
- Within SuperDAO I have methods like performQuery(
String query), performUpdate(String query), etc that performs/executes the passed String query, using the established Connection object.
- I have a couple of OracleDAO's (i.e UserOracleDAO) that extends SuperDAO and within this OracleDAO's resides my calls to performQuery() or updateQuery() of the SuperDAO class. In each OracleDAO I have placed a call to super() in their constructor, which basically establishes a connection.
I have TransferObjects and ListHandlers that I forward to
JSP pages to be retrieved, some of them set to scope = 'page', some of scope 'session'.
Now my PROBLEM is:
After a couple of times clicking back and forth from page to page, the application crashes and the server logs something like:
PWC2785: Cannot serialize session attribute userDetails for session 126658c15dd936e42f4cdbb63a85
I am not sure whether this is because there are ResultSets that have remained unclosed (although I have tried to locate and close each instance of it that I've seen) within the application or is it with the way I assigned the scope of my usebeans. I hope you can forgive me if what I wrote may seem basic but I have just been studying
J2EE and is not too familiar yet with the best practices for it and the implications of using the scope of the variable I am using.
Or can my problem be solved by simply adjusting the settings of my connection pool?
Thank you so much and I appreciate all of your response.
Rgs,
Keenon