Remember this before using Spring Context Loading

This week i faced a strange issue with spring context loading.
My aim is to persist all types of errors occuring in webservices. Hence i have created an helper class and injected the helper class in webservice Impl class as follows:private SaveExceptionHelper saveExceptionHelper;

String[] paths = { "/spring/service.xml"};
ApplicationContext ctx = new ClassPathXmlApplicationContext(paths);
saveExceptionService = (SaveExceptionServiceImpl) ctx.getBean("saveExceptionService");

Also in service.xml i have put tag for SaveExceptionServiceImpl.


Upto this I didnt get any problem in build and deployment.
Later i have used a DAO which is having persitance method of hibernate.
and injected in service.xml under SaveExceptionServiceImpl.

I got an exception like

" abc.def.User class not found"

Where "User.class"" is created in some other project folder and imported in SaveExceptionServiceImpl.


Later i fixed it by using an interface to the helper class as saveExceptionService = (SaveExceptionService) ctx.getBean("saveExceptionService");
And i removed the import of ServiceImpl class.
Moral of the story is:

1. The Importance of using Interfaces in Spring context initialization.
2. The helper classes which has implemenation should not use resources from other projects. Incase, it is using other resources, we need an interface for that class and inject the interface in webservice class. Impl class in context loader xml(service.xml).