JPA Default Methods

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Here are the default methods available in some common repository interfaces:

CrudRepository

CrudRepository provides basic CRUD functionality.

import org.springframework.data.repository.CrudRepository;

public interface UserRepository extends CrudRepository<User, Long> {
    // No custom query methods needed; you get these by default:
}

Default Methods in CrudRepository

• Save

  <S extends T> S save(S entity);

• Find One

  Optional<T> findById(ID primaryKey);

• Exists By Id

  boolean existsById(ID primaryKey);

• Count

  long count();

• Delete By Id

  void deleteById(ID primaryKey);

• Delete Entity

  void delete(T entity);

• Find All

  Iterable<T> findAll();

• Find All (Iterable)

  Iterable<T> findAll(Iterable<ID> ids);

PagingAndSortingRepository

PagingAndSortingRepository extends CrudRepository and adds methods to retrieve entities using pagination and
sorting.

import org.springframework.data.repository.PagingAndSortingRepository;

public interface UserRepository extends PagingAndSortingRepository<User, Long> {
    // No custom query methods needed; you get these by default:
}

Additional Methods in PagingAndSortingRepository

• Find All (Pageable)

  Page<T> findAll(Pageable pageable);

• Find All (Sort)

  Iterable<T> findAll(Sort sort);

JpaRepository

JpaRepository extends PagingAndSortingRepository and adds additional methods that are helpful for JPA-specific
operations, like batch deletions.

import org.springframework.data.jpa.repository.JpaRepository;

public interface UserRepository extends JpaRepository<User, Long> {
    // No custom query methods needed; you get these by default:
}

Additional Methods in JpaRepository

• Save All

  <S extends T> List<S> saveAll(Iterable<S> entities);

• Flush

  void flush();

• Delete In Batch

  void deleteInBatch(Iterable<T> entities);

• Delete All In Batch

  void deleteAllInBatch();

• Get One

  T getOne(ID primaryKey);

Example Repository Interface

Here's an example of how you might define a UserRepository interface without any custom query methods:

import org.springframework.data.jpa.repository.JpaRepository;

public interface UserRepository extends JpaRepository<User, Long> {
    // All default methods are available here.
}

By extending JpaRepository, your UserRepository will automatically have all the CRUD operations provided by
CrudRepository, PagingAndSortingRepository, and additional JPA-specific methods.