The CrudRepository defines the basic Create, Read, Update, and Delete methods. The important methods in CrudRepository are shown in the following code:

    public interface CrudRepository<T, ID extends Serializable>
      extends Repository<T, ID> {
      <S extends T> S save(S entity);
      findOne(ID primaryKey);
      Iterable<T> findAll();
      Long count();
      void delete(T entity);
      boolean exists(ID primaryKey);
      // … more functionality omitted.
    }