So. let's start with Spring beans under the test. I prefer to use Java 5 and annotations to publish regular POJOs as Spring beans and declare dependency injection between beans as well. The bean will be MessageService as in code snippet below:
This bean is pretty simple and just demonstrates two important concepts: exporting POJO as Spring bean (@Component) and using dependency injection (@Autowired). Before diving into how to test it, let's create applicationContext.xml (placed inside WEB-INF folder) file.
OK, now we're ready to write our first test, named MessageServiceTestCase. There are basically several ways to do that, depending which features do you need. The first one looks like:
And that's it! Spring takes care about context initialization, beans creation, dependency injection, etc. If you need application context inside the test, then a little bit different approach could be used (by inheriting test class from AbstractJUnit4SpringContextTests class):
There's one important issue concerning Spring context: only one context will be created for each test class instance (not test method!). If you would like to recreate context for each single test method, you have to adorn these ones with @DirtiesContext annotation. Unfortunately, there is no class-level annotation for that up to 2.5.x versions.