Good resources for becoming more familiar with Struts 1 (for a legacy project)

I'm working on a project with my employer that is built with Struts 1 and coming from having worked in Spring it's quite a difference and can be a bit frustrating. I've gotten fairly comfortable already with being able to figure out, for the most part, how things work in order to fix bugs, etc but now I have some tasks where I actually have to do new development by creating new controllers, etc and things regarding the XML config that I thought would be straightforward aren't working so I'm looking for resources to better learn Struts 1. I've looked at the official docs and they are decent but was wondering if anyone can recommend good books, etc, most of my searches for this co开发者_高级运维me up with stuff for Struts 2. Thanks

Here is a good tutorial. Also, you may check the answers to this question.