This week's book giveaway is in the OCAJP forum. We're giving away four copies of OCA Java SE 8 Programmer I Study Guide 1Z0-808 and have Jeanne Boyarsky & Scott Selikoff on-line! See this thread for details.
What do you mean by "debugging" and what about it do you find being difficult with Struts?
If you're talking about debugging as in "using my IDE's debugger", then it should be no different from using, for example, plain JavaServlets.
If you're talking about "printing out stuff so that I can figure out later what exactly happened that lead to getting HTTP 500 on the browser", again, it should be no different from any other framework.