Spring data - Manual implementation

Question

Is it possible to write my own function implementation along usage of spring repositories?

I would like to actually implement the function

getUserByFirstName() 

and not get it automagically. While i still want to get

getUserById()

automagically from spring-data.

1) is it possible?

2) is it possible to achieve logging for all methods spring data automagically generates? (or should i write them manually with

logger.log("entering method ...");

Answer 1

Yes, you can!!!

There is an amazing feature in Spring data that allows this:

1. Create an interface with your custom method:

   public interface UserRepositoryCustom {
   
       User getUserByFirstName();
   }
   

2. Make your Spring Data interface extends this new interface, as well as the Spring data crud interface (or JPA, Mongo or whatever spring data interface you're extending):

   public interface MySpringDataRepository extends CrudRepository<User, Long>, UserRepositoryCustom {
   
   }
   

3. Create a class that implements only your custom interface. The name of the class must be Impl, for instance: UserRepositoryImpl:

   public class MySpringDataRepositoryImpl implements UserRepositoryCustom {
       public User getUserByFirstName(){
          //Your custom implementation
       }
   }
   

Now, you only need to inject the Spring data repository in your service and you can use both methods: the spring-data implemented method and your custom implemented method:

@Inject private MySpringDataRepository myRepository;

That's it!!

Look at this section in the documentation:

Spring Data Custom implementations

Answer 2

See section 1.3 of the manual for the first requirement:

http://docs.spring.io/spring-data/jpa/docs/1.4.2.RELEASE/reference/html/repositories.html#repositories.single-repository-behaviour

For the second requirement I guess some AOP based solution might work for you well here. See here for example using Spring's AOP support:

logging with AOP in spring?