DAO pattern datasource connection help

Question

After researching and attempting to implement the Data Access Object pattern using the Abstract Factory pattern I run into one problem for which I haven't found a solution.
All of the solutions that I have found hardcode the database connection URL and user credentials into either the concrete DAO factory or the concrete DAO object iteself. However, in the application that I am working with, the user credentials will be entered on a login screen and passed into the business objects that reference the data access objects.
My questions are:
Which object should receive the user credentials and datasource URL to authorize the user? (The storage solution that I am using returns query results based on the user's security settings in the repository.)
How do I abstract this connection information to ensure that if I swap in a different storage solution I won't have to change the business objects or the interface to the DAO factory/objects?

Answer 1

Ideally, one should always use the concrete DAOFactory to get you the database specific connection. The reason being that the one concrete DAOFactory exist for one particular database, and creates/returns DAO objects specialized for firing SQLs to that database.
So writing connection code should be removed from DAO classes and put in the factory class.
Now, coming to your problem.
The user credentials are supplied by the user. These credentials are passed on to your business objects that in turn invoke an operation on a particular DAO to fire a SQL and get back the ResultSet.
The business objects would typically get hold of the AbstractFactory to get the concrete factory, and using the concrete factory handle, it would get the concrete DAO class.
The DAO class in turn would use the concrete DAOFactory to get a connection, fire SQL, get the ResultSet and close/return the connection.
So, the best place to handle your issue is to write a public static final method in your AbstractDAOFactory class that returns you a 'fully configured' concrete DAOFactory class. The right time to use your user supplied credentials is when the AbstractFactory is creating your concrete DAOFactory class.
Why?
Because, every new user would represent a new database connection to your database. And that new user is allowed to do host of things using the number of DAOs that you have. So, ideally, for every user the JDBC connection setup part should be re-configured.
So, just have the AbstractFactory return you a re-configured concrete DAOFactory for every new user by passing this AbstractFactory 2 information:
1. "whichDAOFactory" to return, and
2. "ConfigVO" ValueObject having the UID/PWD.
So extending the example given by Sun:
public static DAOFactory getDAOFactory(int whichFactory, Object ConfigVO)
switch (whichFactory)
case CLOUDSCAPE:
return new CloudscapeDAOFactory().configure(ConfigVO);
So, just by adding an abstract method configure() in the AbstractDAOFactory class to force all the extending concrete class to define their own ways to configure themselve with the user supplied credentials.
Regards