What's a smart way to organize classes in Spring 3 for component-scan?

annotations, java, spring

Solution

Yes - in your main context scan everything except controllers

 <context:component-scan base-package="my.package">
    <context:exclude-filter type="regex" expression="my\.package\.controller.*"/>
 </context:component-scan>

and in your DispatcherServlet context just scan the controller package.

Problem

I've begun work on a new project using Spring 3 and I'm using annotations. I love that I can wire up my classes to get dependencies injected, but I know it's a bad practice to have `context:component-scan` start at the base package. I'm using a `DispatcherServlet` which has its own xml configuration file. In that is also a `context:component-scan`. When I first started learning Spring I had overlap in my component scans and saw beans created multiple times. I'd like to avoid that. What is a good way to organize either my packages or my component scans to cover all the beans without duplication? Currently I have packages like this: ``` my.package.controller my.package.dao my.package.entity my.package.service my.package.util ``` If I have beans in all those packages then it seems like the easy way out would be to put `<context:component-scan base-package="my.package"></context:component-scan>` into applicationContext.xml and be done with it. Would it be better to scan `my.package.controller` in the dispatcher's xml and the rest (excluding my.package.controller) in applicationContext.xml? Or should I arrange all my annotated classes in one area and everything else in another? Something like: ``` my.package.spring.controller my.package.spring.dao my.package.spring.entity my.package.spring.service my.package.spring.util my.package.notannotated my.package.notannotated2 ``` I'm using @Autowired to add logging to most if not all of my classes so I don't know that I'll have any classes that won't be annotated. I hate getting stuck on configuration...I'd rather be stuck in code, so if someone can offer any tips I'd readily welcome them. Thanks!

Original source