Mastering Spring 5.0

A simple repository

A custom repository can be created by extending the repository marker interface. In the following example, we extend the repository interface with two methods--findAll and count:

    import org.springframework.data.repository.Repository;    public interface TodoRepository extends Repository<Todo, Long> {      Iterable<Todo> findAll();      long count();    }

A few important things to note are as follows:

• public interface TodoRepository extends Repository<Todo, Long>: The TodoRepository interface extends the Repository interface. The two generic types indicate the entity being managed--Todo and the type of the primary key, that is, Long.
• Iterable<Todo> findAll(): Used to list all the todos. Note that the name of the method should match what's ...