Question

The init method in most (all) of my servlets is similar. Mostly initializing a DataSource

I am thinking of creating a BaseServlet having a protected DataSource and the init method implemented and all other servlets extend this BaseServlet.

Any Gotchas I should be wary of?

Answer 1

In the current approach:

1. Every Servlet extending BaseServlet will create its own datasource as the init() method will be called multiple times.
2. I assume this is not what you want to accomplish and you are looking for a single datasource to be used across all the Servlets.

Assuming above is true, I would suggest following

1. Wrap your datasource in a singleton class. This will make sure that datasource initialized only once. Use eager initialization to make sure the Datasource is initalized at the class load itself
2. Use this class to get the datasource/connections in your servlet class.