2. JPA Repositories


This chapter includes details of the JPA repository implementation.

2.1 Introduction

2.1.1 Spring namespace

The JPA module of Spring Data contains a custom namespace that allows defining repository beans. It also contains certain features and element attributes that are special to JPA. Generally the JPA repositories can be set up using the repositories element:

Example 2.1. Setting up JPA repositories using the namespace

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"

  <jpa:repositories base-package="com.acme.repositories" />


Using this element looks up Spring Data repositories as described in Section 1.3.3, “Creating repository instances”. Beyond that it activates persistence exception translation for all beans annotated with @Repository to let exceptions being thrown by the JPA presistence providers be converted into Spring's DataAccessException hierarchy.

Custom namespace attributes

Beyond the default attributes of the repositories element the JPA namespace offers additional attributes to gain more detailled control over the setup of the repositories:

Table 2.1. Custom JPA-specific attributes of the repositories element

entity-manager-factory-refExplicitly wire the EntityManagerFactory to be used with the repositories being detected by the repositories element. Usually used if multiple EntityManagerFactory beans are used within the application. If not configured we will automatically lookup the single EntityManagerFactory configured in the ApplicationContext.
transaction-manager-refExplicitly wire the PlatformTransactionManager to be used with the repositories being detected by the repositories element. Usually only necessary if multiple transaction managers and/or EntityManagerFactory beans have been configured. Default to a single defined PlatformTransactionManager inside the current ApplicationContext.

2.1.2 Annotation based configuration

The Spring Data JPA repositories support cannot only be activated through an XML namespace but also using an annotation through JavaConfig.

Example 2.2. Spring Data JPA repositories using JavaConfig

class ApplicationConfig {

  public DataSource dataSource() {

    EmbeddedDatabaseBuilder builder = new EmbeddedDatabaseBuilder();
    return builder.setType(EmbeddedDatabaseType.HSQL).build();

  public EntityManagerFactory entityManagerFactory() {

    HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();

    LocalContainerEntityManagerFactoryBean factory = new LocalContainerEntityManagerFactoryBean();

    return factory.getObject();

  public PlatformTransactionManager transactionManager() {

    JpaTransactionManager txManager = new JpaTransactionManager();
    return txManager;

The just shown configuration class sets up an embedded HSQL database using the EmbeddedDatabaseBuilder API of spring-jdbc. We then set up a EntityManagerFactory and use Hibernate as sample persistence provider. The last infrastructure component declared here is the JpaTransactionManager. We eventually activate Spring Data JPA repositories using the @EnableJpaRepositories annotation which essentially carries the same attributes as the XML namespace does. If no base package is configured it will use the one the configuration class resides in.

2.2 Query methods

2.2.1 Query lookup strategies

The JPA module supports defining a query manually as String or have it being derived from the method name.

Declared queries

Although getting a query derived from the method name is quite convenient, one might face the situation in which either the method name parser does not support the keyword one wants to use or the method name would get unnecessarily ugly. So you can either use JPA named queries through a naming convention (see Section 2.2.3, “Using JPA NamedQueries” for more information) or rather annotate your query method with @Query (see Section 2.2.4, “Using @Query” for details).

2.2.2 Query creation

Generally the query creation mechanism for JPA works as described in Section 1.3, “Query methods”. Here's a short example of what a JPA query method translates into:

Example 2.3. Query creation from method names

public interface UserRepository extends Repository<User, Long> {

  List<User> findByEmailAddressAndLastname(String emailAddress, String lastname);

We will create a query using the JPA criteria API from this but essentially this translates into the following query:

select u from User u where u.emailAddress = ?1 and u.lastname = ?2

Spring Data JPA will do a property check and traverse nested properties as described in the section called “Property expressions”. Here's an overview of the keywords supported for JPA and what a method containing that keyword essentially translates to.

Table 2.2. Supported keywords inside method names

KeywordSampleJPQL snippet
AndfindByLastnameAndFirstname… where x.lastname = ?1 and x.firstname = ?2
OrfindByLastnameOrFirstname… where x.lastname = ?1 or x.firstname = ?2
BetweenfindByStartDateBetween… where x.startDate between 1? and ?2
LessThanfindByAgeLessThan… where x.age < ?1
GreaterThanfindByAgeGreaterThan… where x.age > ?1
AfterfindByStartDateAfter… where x.startDate > ?1
BeforefindByStartDateBefore… where x.startDate < ?1
IsNullfindByAgeIsNull… where x.age is null
IsNotNull,NotNullfindByAge(Is)NotNull… where x.age not null
LikefindByFirstnameLike… where x.firstname like ?1
NotLikefindByFirstnameNotLike… where x.firstname not like ?1
StartingWithfindByFirstnameStartingWith… where x.firstname like ?1 (parameter bound with appended %)
EndingWithfindByFirstnameEndingWith… where x.firstname like ?1 (parameter bound with prepended %)
ContainingfindByFirstnameContaining… where x.firstname like ?1 (parameter bound wrapped in %)
OrderByfindByAgeOrderByLastnameDesc… where x.age = ?1 order by x.lastname desc
NotfindByLastnameNot… where x.lastname <> ?1
InfindByAgeIn(Collection<Age> ages)… where x.age in ?1
NotInfindByAgeNotIn(Collection<Age> age)… where x.age not in ?1
TruefindByActiveTrue()… where x.active = true
FalsefindByActiveFalse()… where x.active = false


In and NotIn also take any subclass of Collection as parameter as well as arrays or varargs. For other syntactical versions of the very same logical operator check Appendix B, Repository query keywords.

2.2.3 Using JPA NamedQueries


The examples use simple <named-query /> element and @NamedQuery annotation. The queries for these configuration elements have to be defined in JPA query language. Of course you can use <named-native-query /> or @NamedNativeQuery too. These elements allow you to define the query in native SQL by losing the database platform independence.

XML named query definition

To use XML configuration simply add the necessary <named-query /> element to the orm.xml JPA configuration file located in META-INF folder of your classpath. Automatic invocation of named queries is enabled by using some defined naming convention. For more details see below.

Example 2.4. XML named query configuration

<named-query name="User.findByLastname">
  <query>select u from User u where u.lastname = ?1</query>

As you can see the query has a special name which will be used to resolve it at runtime.

Annotation configuration

Annotation configuration has the advantage of not needing another configuration file to be edited, probably lowering maintenance costs. You pay for that benefit by the need to recompile your domain class for every new query declaration.

Example 2.5. Annotation based named query configuration

@NamedQuery(name = "User.findByEmailAddress",
  query = "select u from User u where u.emailAddress = ?1")
public class User {


Declaring interfaces

To allow execution of these named queries all you need to do is to specify the UserRepository as follows:

Example 2.6. Query method declaration in UserRepository

public interface UserRepository extends JpaRepository<User, Long> {

  List<User> findByLastname(String lastname);

  User findByEmailAddress(String emailAddress);

Spring Data will try to resolve a call to these methods to a named query, starting with the simple name of the configured domain class, followed by the method name separated by a dot. So the example here would use the named queries defined above instead of trying to create a query from the method name.

2.2.4 Using @Query

Using named queries to declare queries for entities is a valid approach and works fine for a small number of queries. As the queries themselves are tied to the Java method that executes them you actually can bind them directly using the Spring Data JPA @Query annotation rather than annotating them to the domain class. This will free the domain class from persistence specific information and co-locate the query to the repository interface.

Queries annotated to the query method will take precedence over queries defined using @NamedQuery or named queries declared in orm.xml.

Example 2.7. Declare query at the query method using @Query

public interface UserRepository extends JpaRepository<User, Long> {

  @Query("select u from User u where u.emailAddress = ?1")
  User findByEmailAddress(String emailAddress);

Native queries

The @Query annotation allows to execute native queries by setting the nativeQuery flag to true. Note, that we currently don't support execution of pagination or dynamic sorting for native queries as we'd have to manipulate the actual query declared and we cannot do this reliably for native SQL.

Example 2.8. Declare a native query at the query method using @Query

public interface UserRepository extends JpaRepository<User, Long> {

  @Query(value = "SELECT FROM USERS WHERE EMAIL_ADDRESS = ?0", nativeQuery = true)
  User findByEmailAddress(String emailAddress);

2.2.5 Using named parameters

By default Spring Data JPA will use position based parameter binding as described in all the samples above. This makes query methods a little error prone to refactoring regarding the parameter position. To solve this issue you can use @Param annotation to give a method parameter a concrete name and bind the name in the query:

Example 2.9. Using named parameters

public interface UserRepository extends JpaRepository<User, Long> {

  @Query("select u from User u where u.firstname = :firstname or u.lastname = :lastname")
  User findByLastnameOrFirstname(@Param("lastname") String lastname,
                                 @Param("firstname") String firstname);

Note that the method parameters are switched according to the occurrence in the query defined.

2.2.6 Modifying queries

All the sections above describe how to declare queries to access a given entity or collection of entities. Of course you can add custom modifying behaviour by using facilities described in Section 1.4, “Custom implementations”. As this approach is feasible for comprehensive custom functionality, you can achieve the execution of modifying queries that actually only need parameter binding by annotating the query method with @Modifying:

Example 2.10. Declaring manipulating queries

@Query("update User u set u.firstname = ?1 where u.lastname = ?2")
int setFixedFirstnameFor(String firstname, String lastname);

This will trigger the query annotated to the method as updating query instead of a selecting one. As the EntityManager might contain outdated entities after the execution of the modifying query, we automatically clear it (see JavaDoc of EntityManager.clear() for details). This will effectively drop all non-flushed changes still pending in the EntityManager. If you don't wish the EntityManager to be cleared automatically you can set @Modifying annotation's clearAutomatically attribute to false;

2.2.7 Applying query hints

To apply JPA QueryHints to the queries declared in your repository interface you can use the QueryHints annotation. It takes an array of JPA QueryHint annotations plus a boolean flag to potentially disable the hints applied to the addtional count query triggered when applying pagination.

Example 2.11. Using QueryHints with a repository method

public interface UserRepository extends Repository<User, Long> {

  @QueryHints(value = { @QueryHint(name = "name", value = "value")}, 
              forCounting = false)
  Page<User> findByLastname(String lastname, Pageable pageable);

The just shown declaration would apply the configured QueryHint for that actually query but omit applying it to the count query triggered to calculate the total number of pages.

2.3 Specifications

JPA 2 introduces a criteria API that can be used to build queries programmatically. Writing a criteria you actually define the where-clause of a query for a domain class. Taking another step back these criteria can be regarded as predicate over the entity that is described by the JPA criteria API constraints.

Spring Data JPA takes the concept of a specification from Eric Evans' book "Domain Driven Design", following the same semantics and providing an API to define such Specifications using the JPA criteria API. To support specifications you can extend your repository interface with the JpaSpecificationExecutor interface:

public interface CustomerRepository extends CrudRepository<Customer, Long>, JpaSpecificationExecutor {

The additional interface carries methods that allow you to execute Specifications in a variety of ways.

For example, the findAll method will return all entities that match the specification:

List<T> findAll(Specification<T> spec);

The Specification interface is as follows:

public interface Specification<T> {
  Predicate toPredicate(Root<T> root, CriteriaQuery<?> query,
            CriteriaBuilder builder);

Okay, so what is the typical use case? Specifications can easily be used to build an extensible set of predicates on top of an entity that then can be combined and used with JpaRepository without the need to declare a query (method) for every needed combination. Here's an example:

Example 2.12. Specifications for a Customer

public class CustomerSpecs {

  public static Specification<Customer> isLongTermCustomer() {
    return new Specification<Customer>() {
      public Predicate toPredicate(Root<Customer> root, CriteriaQuery<?> query,
            CriteriaBuilder builder) {

         LocalDate date = new LocalDate().minusYears(2);
         return builder.lessThan(root.get(Customer_.createdAt), date);

  public static Specification<Customer> hasSalesOfMoreThan(MontaryAmount value) {
    return new Specification<Customer>() {
      public Predicate toPredicate(Root<T> root, CriteriaQuery<?> query,
            CriteriaBuilder builder) {

         // build query here

Admittedly the amount of boilerplate leaves room for improvement (that will hopefully be reduced by Java 8 closures) but the client side becomes much nicer as you will see below. The Customer_ type is a metamodel type generated using the JPA Metamodel generator (see the Hibernate implementation's documentation for example). So the expression Customer_.createdAt is asuming the Customer having a createdAt attribute of type Date. Besides that we have expressed some criteria on a business requirement abstraction level and created executable Specifications. So a client might use a Specification as follows:

Example 2.13. Using a simple Specification

List<Customer> customers = customerRepository.findAll(isLongTermCustomer());

Okay, why not simply create a query for this kind of data access? You're right. Using a single Specification does not gain a lot of benefit over a plain query declaration. The power of Specifications really shines when you combine them to create new Specification objects. You can achieve this through the Specifications helper class we provide to build expressions like this:

Example 2.14. Combined Specifications

MonetaryAmount amount = new MonetaryAmount(200.0, Currencies.DOLLAR);
List<Customer> customers = customerRepository.findAll(

As you can see, Specifications offers some glue-code methods to chain and combine Specifications. Thus extending your data access layer is just a matter of creating new Specification implementations and combining them with ones already existing.

2.4 Transactionality

CRUD methods on repository instances are transactional by default. For reading operations the transaction configuration readOnly flag is set to true, all others are configured with a plain @Transactional so that default transaction configuration applies. For details see JavaDoc of Repository. If you need to tweak transaction configuration for one of the methods declared in Repository simply redeclare the method in your repository interface as follows:

Example 2.15. Custom transaction configuration for CRUD

public interface UserRepository extends JpaRepository<User, Long> {

  @Transactional(timeout = 10)
  public List<User> findAll();

  // Further query method declarations

This will cause the findAll() method to be executed with a timeout of 10 seconds and without the readOnly flag.

Another possibility to alter transactional behaviour is using a facade or service implementation that typically covers more than one repository. Its purpose is to define transactional boundaries for non-CRUD operations:

Example 2.16. Using a facade to define transactions for multiple repository calls

class UserManagementImpl implements UserManagement {

  private final UserRepository userRepository;
  private final RoleRepository roleRepository;

  public UserManagementImpl(UserRepository userRepository,
    RoleRepository roleRepository) {
    this.userRepository = userRepository;
    this.roleRepository = roleRepository;

  public void addRoleToAllUsers(String roleName) {

    Role role = roleRepository.findByName(roleName);

    for (User user : userRepository.findAll()) {

This will cause call to addRoleToAllUsers(…) to run inside a transaction (participating in an existing one or create a new one if none already running). The transaction configuration at the repositories will be neglected then as the outer transaction configuration determines the actual one used. Note that you will have to activate <tx:annotation-driven /> explicitly to get annotation based configuration at facades working. The example above assumes you are using component scanning.

2.4.1 Transactional query methods

To allow your query methods to be transactional simply use @Transactional at the repository interface you define.

Example 2.17. Using @Transactional at query methods

@Transactional(readOnly = true)
public interface UserRepository extends JpaRepository<User, Long> {

  List<User> findByLastname(String lastname);

  @Query("delete from User u where u.active = false")
  void deleteInactiveUsers();

Typically you will want the readOnly flag set to true as most of the query methods will only read data. In contrast to that deleteInactiveUsers() makes use of the @Modifying annotation and overrides the transaction configuration. Thus the method will be executed with readOnly flag set to false.


It's definitely reasonable to use transactions for read only queries and we can mark them as such by setting the readOnly flag. This will not, however, act as check that you do not trigger a manipulating query (although some databases reject INSERT and UPDATE statements inside a read only transaction). The readOnly flag instead is propagated as hint to the underlying JDBC driver for performance optimizations. Furthermore, Spring will perform some optimizations on the underlying JPA provider. E.g. when used with Hibernate the flush mode is set to NEVER when you configure a transaction as readOnly which causes Hibernate to skip dirty checks (a noticeable improvement on large object trees).

2.5 Locking

To specify the lock mode to be used the @Lock annotation can be used on query methods:

Example 2.18. Defining lock metadata on query methods

interface UserRepository extends Repository<User, Long> {

  // Plain query method
  List<User> findByLastname(String lastname);

This method declaration will cause the query being triggered to be equipped with the LockModeType READ. You can also define locking for CRUD methods by redeclaring them in your repository interface and adding the @Lock annotation:

Example 2.19. Defining lock metadata on CRUD methods

interface UserRepository extends Repository<User, Long> {

  // Redeclaration of a CRUD method
  List<User> findAll();

2.6 Auditing

2.6.1 Basics

Spring Data provides sophisticated support to transparently keep track of who created or changed an entity and the point in time this happened. To benefit from that functionality you have to equip your entity classes with auditing metadata that can be defined either using annotations or by implementing an interface.

Annotation based auditing metadata

We provide @CreatedBy, @LastModifiedBy to capture the user who created or modified the entity as well as @CreatedDate and @LastModifiedDate to capture the point in time this happened.

Example 2.20. An audited entity

class Customer {

  private User user;
  private DateTime createdDate;

  // … further properties omitted

As you can see, the annotations can be applied selectively, depending on which information you'd like to capture. For the annotations capturing the points in time can be used on properties of type org.joda.time.DateTime, java.util.Date as well as long/Long.

Interface-based auditing metadata

In case you don't want to use annotations to define auditing metadata you can let your domain class implement the Auditable interface. It exposes setter methods for all of the auditing properties.

There's also a convenience base class AbstractAuditable which you can extend to avoid the need to manually implement the interface methods. Be aware that this increases the coupling of your domain classes to Spring Data which might be something you want to avoid. Usually the annotation based way of defining auditing metadata is preferred as it is less invasive and more flexible.


In case you use either @CreatedBy or @LastModifiedBy, the auditing infrastructure somehow needs to become aware of the current principal. To do so, we provide an AuditorAware<T> SPI interface that you have to implement to tell the infrastructure who the current user or system interacting with the application is. The generic type T defines of what type the properties annotated with @CreatedBy or @LastModifiedBy have to be.

Here's an example implementation of the interface using Spring Security's Authentication object:

Example 2.21. Implementation of AuditorAware based on Spring Security

class SpringSecurityAuditorAware implements AuditorAware<User> {

  public User getCurrentAuditor() {
    Authentication authentication = SecurityContextHolder.getContext().getAuthentication();

    if (authentication == null || !authentication.isAuthenticated()) {
      return null;

    return ((MyUserDetails) authentication.getPrincipal()).getUser();

The implementation is accessing the Authentication object provided by Spring Security and looks up the custom UserDetails instance from it that you have created in your UserDetailsService implementation. We're assuming here that you are exposing the domain user through that UserDetails implementation but you could also look it up from anywhere based on the Authentication found.

2.6.2 General auditing configuration

Spring Data JPA ships with an entity listener that can be used to trigger capturing auditing information. So first you have to register the AuditingEntityListener inside your orm.xml to be used for all entities in your persistence contexts:

Example 2.22. Auditing configuration orm.xml

      <entity-listener class="….data.jpa.domain.support.AuditingEntityListener" />

Now activating auditing functionality is just a matter of adding the Spring Data JPA auditing namespace element to your configuration:

Example 2.23. Activating auditing in the Spring configuration

<jpa:auditing auditor-aware-ref="yourAuditorAwareBean" />

As you can see you have to provide a bean that implements the AuditorAware interface which looks as follows:

Example 2.24. AuditorAware interface

public interface AuditorAware<T, ID extends Serializable> {

    T getCurrentAuditor();

Usually you will have some kind of authentication component in your application that tracks the user currently working with the system. This component should be AuditorAware and thus allow seamless tracking of the auditor.

2.7 Miscellaneous

2.7.1 Merging persistence units

Spring supports having multiple persistence units out of the box. Sometimes, however, you might want to modularize your application but still make sure that all these modules run inside a single persistence unit at runtime. To do so Spring Data JPA offers a PersistenceUnitManager implementation that automatically merges persistence units based on their name.

Example 2.25. Using MergingPersistenceUnitmanager

<bean class="….LocalContainerEntityManagerFactoryBean">
  <property name="persistenceUnitManager">
    <bean class="….MergingPersistenceUnitManager" />

2.7.2 Classpath scanning for @Entity classes and JPA mapping files

A plain JPA setup requires all annotation mapped entity classes listed in orm.xml. Same applies to XML mapping files. Spring Data JPA provides a ClasspathScanningPersistenceUnitPostProcessor that gets a base package configured and optionally takes a mapping filename pattern. It will then scan the given package for classes annotated with @Entity or @MappedSuperclass and also loads the configuration files matching the filename pattern and hands them to the JPA configuration. The PostProcessor has to be configured like this

Example 2.26. Using ClasspathScanningPersistenceUnitPostProcessor

<bean class="….LocalContainerEntityManagerFactoryBean">
  <property name="persistenceUnitPostProcessors">
      <bean class="org.springframework.data.jpa.support.ClasspathScanningPersistenceUnitPostProcessor">
        <constructor-arg value="com.acme.domain" />
        <property name="mappingFileNamePattern" value="**/*Mapping.xml" />


As of Spring 3.1 a package to scan can be configured on the LocalContainerEntityManagerFactoryBean directly to enable classpath scanning for entity classes. See the JavaDoc for details.

2.7.3 CDI integration

Instances of the repository interfaces are usually created by a container, which Spring is the most natural choice when working with Spring Data. There's sophisticated support to easily set up Spring to create bean instances documented in Section 1.3.3, “Creating repository instances”. As of version 1.1.0 Spring Data JPA ships with a custom CDI extension that allows using the repository abstraction in CDI environments. The extension is part of the JAR so all you need to do to activate it is dropping the Spring Data JPA JAR into your classpath.

You can now set up the infrastructure by implementing a CDI Producer for the EntityManagerFactory:

class EntityManagerFactoryProducer {

  public EntityManagerFactory createEntityManagerFactory() {
    return Persistence.createEntityManagerFactory("my-presistence-unit");

  public void close(@Disposes EntityManagerFactory entityManagerFactory) {

The Spring Data JPA CDI extension will pick up all EntityManagers availables as CDI beans and create a proxy for a Spring Data repository whenever an bean of a repository type is requested by the container. Thus obtaining an instance of a Spring Data repository is a matter of declaring an @Injected property:

class RepositoryClient {

  PersonRepository repository;

  public void businessMethod() {

    List<Person> people = repository.findAll();