Spring Data JPA - Reference Documentation


Oliver Gierke

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Revision History
09.02.2011Oliver Gierke
Initial port from Hades documentation

1. Project metadata
I. Reference Documentation
1. Repositories
1.1. Introduction
1.2. Core concepts
1.3. Query methods
1.3.1. Defining repository interfaces Fine tuning repository definition
1.3.2. Defining query methods Query lookup strategies Query creation Special parameter handling
1.3.3. Creating repository instances Spring Standalone usage
1.4. Custom implementations
1.4.1. Adding behaviour to single repositories
1.4.2. Adding custom behaviour to all repositories
2. JPA Repositories
2.1. Introduction
2.1.1. Spring namespace
2.2. Query methods
2.2.1. Query lookup strategies
2.2.2. Query creation
2.2.3. Using JPA NamedQueries
2.2.4. Using @Query
2.2.5. Using named parameters
2.2.6. Modifying queries
2.3. Specifications
2.4. Transactionality
2.4.1. Transactional query methods
2.5. Auditing
2.6. Miscellaneous
2.6.1. Merging persistence units
II. Appendix
A. Namespace reference
A.1. The <repositories /> element
A.2. The <repository /> element
B. Frequently asked questions


Part I. Reference Documentation

Chapter 1. Repositories

1.1. Introduction

Implementing a data access layer of an application has been cumbersome for quite a while. Too much boilerplate code had to be written. Domain classes were anemic and haven't been designed in a real object oriented or domain driven manner.

Using both of these technologies makes developers life a lot easier regarding rich domain model's persistence. Nevertheless the amount of boilerplate code to implement repositories especially is still quite high. So the goal of the repository abstraction of Spring Data is to reduce the effort to implement data access layers for various persistence stores significantly.

The following chapters will introduce the core concepts and interfaces of Spring Data repositories.

1.2. Core concepts

The central interface in Spring Data repository abstraction is Repository (probably not that much of a surprise). It is typeable to the domain class to manage as well as the id type of the domain class. This interface mainly acts as marker interface to capture the types to deal with and helps us discovering interface that extend this one. Beyond that there's CrudRepository which provides some sophisticated functionality around CRUD for the entity managed.

Example 1.1. Repository interface

public interface CrudRepository<T, ID extends Serializable> 
    extends Repository<T, ID> {
    T save(T entity);
    T findOne(ID primaryKey);
    Iterable<T> findAll();

    Long count();
    void delete(T entity);
    boolean exists(ID primaryKey);
    // … more functionality omitted.

Saves the given entity.


Returns the entity identified by the given id.


Returns all entities.


Returns the number of entities.


Deletes the given entity.


Returns whether an entity with the given id exists.

Usually we will have persistence technology specific sub-interfaces to include additional technology specific methods. We will now ship implementations for a variety of Spring Data modules that implement that interface.

On top of the CrudRepository there is a PagingAndSortingRepository abstraction that adds additional methods to ease paginated access to entities:

Example 1.2. PagingAndSortingRepository

public interface PagingAndSortingRepository<T, ID extends Serializable> extends CrudRepository<T, ID> {

    Iterable<T> findAll(Sort sort);

    Page<T> findAll(Pageable pageable);

Accessing the second page of User by a page size of 20 you could simply do something like this:

PagingAndSortingRepository<User, Long> repository = // … get access to a bean
Page<User> users = repository.findAll(new PageRequest(1, 20);

1.3. Query methods

Next to standard CRUD functionality repositories are usually query the underlying datastore. With Spring Data declaring those queries becomes a four-step process.

  1. Declare an interface extending Repository or one of it's sub-interfaces and type it to the domain class it shall handle.

    public interface PersonRepository extends Repository<User, Long> { … }
  2. Declare query methods on the interface.

    List<Person> findByLastname(String lastname);
  3. Setup Spring to create proxy instances for those interfaces.

    <?xml version="1.0" encoding="UTF-8"?>
    <beans:beans xmlns:beans="http://www.springframework.org/schema/beans"
      <repositories base-package="com.acme.repositories" />
  4. Get the repository instance injected and use it.

    public class SomeClient {
      private PersonRepository repository;
      public void doSomething() {
        List<Person> persons = repository.findByLastname("Matthews");

At this stage we barely scratched the surface of what's possible with the repositories but the general approach should be clear. Let's go through each of these steps and and figure out details and various options that you have at each stage.

1.3.1. Defining repository interfaces

As a very first step you define a domain class specific repository interface to start with. It's got to extend Repository and be typed to the domain class and an ID type. If you want to expose CRUD methods for that domain type, extend CrudRepository instead of Repository. Fine tuning repository definition

Usually you will have your repository interface extend Repository, CrudRepository or PagingAndSortingRepository. If you don't like extending Spring Data interfaces at all you can also annotate your repository interface with @RepositoryDefinition. Extending CrudRepository will expose a complete set of methods to manipulate your entities. If you rather want to be selective about the methods being expose simply copy the ones you want to expose from CrudRepository into your domain repository.

Example 1.3. Selectively exposing CRUD methods

interface MyBaseRepository<T, ID extends Serializable> extends Repository<T, ID> {
  T findOne(ID id);
  T save(T entity);

interface UserRepository extends MyBaseRepository<User, Long> {

  User findByEmailAddress(EmailAddress emailAddress);

In the first step we define a common base interface for all our domain repositories and expose findOne(…) as well as save(…).These methods will be routed into the base repository implementation of the store of your choice because they are matching the method signatures in CrudRepository. So our UserRepository will now be able to save users, find single ones by id as well as triggering a query to find Users by their email address.

1.3.2. Defining query methods Query lookup strategies

The next thing we have to discuss is the definition of query methods. There's roughly two main ways how the repository proxy is generally able to come up with the store specific query from the method name. The first option is to derive the quer from the method name directly, the second is using some kind of additionally created query. What detailed options are available pretty much depends on the actual store. However there's got to be some algorithm the decision which actual query to is made.

There's three strategies for the repository infrastructure to resolve the query. The strategy to be used can be configured at the namespace through the query-lookup-strategy attribute. However might be the case that some of the strategies are not supported for the specific datastore. Here are your options:


This strategy will try to construct a store specific query from the query method's name. The general approach is to remove a given set of well-known prefixes from the method name and parse the rest of the method. Read more about query construction in Section, “Query creation”.


This strategy tries to find a declared query which will be used for execution first. The query could be defined by an annotation somwhere or declared by other means. Please consult the documentation of the specific store to find out what options are available for that store. If the repository infrastructure does not find a declared query for the method at bootstrap time it will fail.


This strategy is actually a combination of the both mentioned above. It will try to lookup a declared query first but create a custom method name based query if no declared query was found. This is default lookup strategy and thus will be used if you don't configure anything explicitly. It allows quick query definition by method names but also custom tuning of these queries by introducing declared queries for those who need explicit tuning. Query creation

The query builder mechanism built into Spring Data repository infrastructue is useful to build constraining queries over entities of the repository. We will strip the prefixes findBy, find, readBy, read, getBy as well as get from the method and start parsing the rest of it. At a very basic level you can define conditions on entity properties and concatenate them with AND and OR.

Example 1.4. Query creation from method names

public interface PersonRepository extends Repository<User, Long> {

  List<Person> findByEmailAddressAndLastname(EmailAddress emailAddress, String lastname);

The actual result of parsing that method will of course depend on the persistence store we create the query for. However there are some general things to notice. The expression are usually property traversals combined with operators that can be concatenated. As you can see in the example you can combine property expressions with And and Or. Beyond that you will get support for various operators like Between, LessThan, GreaterThan, Like for the property expressions. As the operators supported can vary from datastore to datastore please consult the according part of the reference documentation. Property expressions

Property expressions can just refer to a direct property of the managed entity (as you just saw in the example above. On query creation time we already make sure that the parsed property is at a property of the managed domain class. However you can also traverse nested properties to define constraints on. Assume Persons have Addresses with ZipCodes. In that case a method name of

List<Person> findByAddressZipCode(ZipCode zipCode);

will create the property traversal x.address.zipCode. The resolution algorithm starts with interpreting the entire part (AddressZipCode) as property and checks the domain class for a property with that name (uncapitalized). If it succeeds it just uses that. If not it starts splitting up the source at the camel case parts from the right side into a head and a tail and tries to find the according property, e.g. AddressZip and Code. If we find a property with that head we take the tail and continue building the tree down from there. As in our case the first split does not match we move the split point to the left (Address, ZipCode).

Now although this should work for most cases, there might be cases where the algorithm could select the wrong property. Suppose our Person class has a addressZip property as well. Then our algorithm would match in the first split round already and essentially choose the wrong property and finally fail (as the type of addressZip probably has no code property). To resolve this ambiguity you can use _ inside your method name to manually define traversal points. So our method name would end up like so:

List<Person> findByAddress_ZipCode(ZipCode zipCode); Special parameter handling

To hand parameters to your query you simply define method parameters as already seen in in examples above. Besides that we will recognizes certain specific types to apply pagination and sorting to your queries dynamically.

Example 1.5. Using Pageable and Sort in query methods

Page<User> findByLastname(String lastname, Pageable pageable);

List<User> findByLastname(String lastname, Sort sort);

List<User> findByLastname(String lastname, Pageable pageable);

The first method allows you to pass a Pageable instance to the query method to dynamically add paging to your statically defined query. Sorting options are handed via the Pageable instance, too. If you only need sorting, simply add a Sort parameter to your method. As you also can see, simply returning a List is possible as well. We will then not retrieve the additional metadata required to build the actual Page instance but rather simply restrict the query to lookup only the given range of entities.


To find out how many pages you get for a query entirely we have to trigger an additional count query. This will be derived from the query you actually trigger by default.

1.3.3. Creating repository instances

So now the question is how to create instances and bean definitions for the repository interfaces defined. Spring

The easiest way to do so is by using the Spring namespace that is shipped with each Spring Data module that supports the repository mechanism. Each of those includes a repositories element that allows you to simply define a base packge Spring shall scan for you.

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

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


In this case we instruct Spring to scan com.acme.repositories and all it's sub packages for interfaces extending Repository or one of its sub-interfaces. For each interface found it will register the presistence technology specific FactoryBean to create the according proxies that handle invocations of the query methods. Each of these beans will be registered under a bean name that is derived from the interface name, so an interface of UserRepository would be registered under userRepository. The base-package attribute allows to use wildcards, so that you can have a pattern of packages parsed.

Using filters

By default we will pick up every interface extending the persistence technology specific Repository sub-interface located underneath the configured base package and create a bean instance for it. However, you might want to gain finer grained control over which interfaces bean instances get created for. To do this we support the use of <include-filter /> and <exclude-filter /> elements inside <repositories />. The semantics are exactly equivalent to the elements in Spring's context namespace. For details see Spring reference documentation on these elements.

E.g. to exclude certain interfaces from instantiation as repository, you could use the following configuration:

Example 1.6. Using exclude-filter element

<repositories base-package="com.acme.repositories">
  <context:exclude-filter type="regex" expression=".*SomeRepository" />

This would exclude all interface ending on SomeRepository from being instantiated.

Manual configuration

If you'd rather like to manually define which repository instances to create you can do this with nested <repository /> elements.

<repositories base-package="com.acme.repositories">
  <repository id="userRepository" />
</repositories> Standalone usage

You can also use the repository infrastructure outside of a Spring container usage. You will still need to have some of the Spring libraries on your classpath but you can generally setup repositories programatically as well. The Spring Data modules providing repository support ship a persistence technology specific RepositoryFactory that can be used as follows:

Example 1.7. Standalone usage of repository factory

RepositoryFactorySupport factory = … // Instantiate factory here
UserRepository repository = factory.getRepository(UserRepository.class);

1.4. Custom implementations

1.4.1. Adding behaviour to single repositories

Often it is necessary to provide a custom implementation for a few repository methods. Spring Data repositories easily allow provide custom repository code and integrate it with generic CRUD abstraction and query method functionality. To enrich a repository with custom functionality you have to define an interface and an implementation for that functionality first and let the repository interface you provided so far extend that custom interface.

Example 1.8. Interface for custom repository functionality

interface UserRepositoryCustom {

  public void someCustomMethod(User user);

Example 1.9. Implementation of custom repository functionality

class UserRepositoryImpl implements UserRepositoryCustom {

  public void someCustomMethod(User user) {
    // Your custom implementation

Note that the implementation itself does not depend on Spring Data and can be a regular Spring bean. So you can either use standard dependency injection behaviour to inject references to other beans, take part in aspects and so on.

Example 1.10. Changes to the your basic repository interface

public interface UserRepository extends CrudRepository<User, Long>, UserRepositoryCustom {

  // Declare query methods here

Let your standard repository interface extend the custom one. This makes CRUD and custom functionality available to clients.


If you use namespace configuration the repository infrastructure tries to autodetect custom implementations by looking up classes in the package we found a repository using the naming conventions appending the namespace element's attribute repository-impl-postfix to the classname. This suffix defaults to Impl.

Example 1.11. Configuration example

<repositories base-package="com.acme.repository">
  <repository id="userRepository" />

<repositories base-package="com.acme.repository" repository-impl-postfix="FooBar">
  <repository id="userRepository" />

The first configuration example will try to lookup a class com.acme.repository.UserRepositoryImpl to act as custom repository implementation, where the second example will try to lookup com.acme.repository.UserRepositoryFooBar.

Manual wiring

The approach above works perfectly well if your custom implementation uses annotation based configuration and autowring entirely as will be trated as any other Spring bean. If your customly implemented bean needs some special wiring you simply declare the bean and name it after the conventions just descibed. We will then pick up the custom bean by name rather than creating an own instance.

Example 1.12. Manual wiring of custom implementations (I)

<repositories base-package="com.acme.repository">
  <repository id="userRepository" />

<beans:bean id="userRepositoryImpl" class="…">
  <!-- further configuration -->

This also works if you use automatic repository lookup without defining single <repository /> elements.

In case you are not in control of the implementation bean name (e.g. if you wrap a generic repository facade around an existing repository implementation) you can explicitly tell the <repository /> element which bean to use as custom implementation by using the repository-impl-ref attribute.

Example 1.13. Manual wiring of custom implementations (II)

<repositories base-package="com.acme.repository">
  <repository id="userRepository" repository-impl-ref="customRepositoryImplementation" />

<bean id="customRepositoryImplementation" class="…">
  <!-- further configuration -->

1.4.2. Adding custom behaviour to all repositories

In other cases you might want to add a single method to all of your repository interfaces. So the approach just shown is not feasible. The first step to achieve this is adding and intermediate interface to declare the shared behaviour

Example 1.14. An interface declaring custom shared behaviour

public interface MyRepository<T, ID extends Serializable> 
  extends JpaRepository<T, ID> {

  void sharedCustomMethod(ID id);

Now your individual repository interfaces will extend this intermediate interface to include the functionality declared. The second step is to create an implementation of this interface that extends the persistence technology specific repository base class which will act as custom base class for the repository proxies then.


If you're using automatic repository interface detection using the Spring namespace using the interface just as is will cause Spring trying to create an instance of MyRepository. This is of course not desired as it just acts as indermediate between Repository and the actual repository interfaces you want to define for each entity. To exclude an interface extending Repository from being instantiated as repository instance annotate it with @NoRepositoryBean.

Example 1.15. Custom repository base class

public class MyRepositoryImpl<T, ID extends Serializable> 
  extends SimpleJpaRepository<T, ID> implements MyRepository<T, ID> {

  public void sharedCustomMethod(ID id) {
    // implementation goes here

The last step to get this implementation used as base class for Spring Data repositores is replacing the standard RepositoryFactoryBean with a custom one using a custom RepositoryFactory that in turn creates instances of your MyRepositoryImpl class.

Example 1.16. Custom repository factory bean

public class MyRepositoryFactoryBean<T extends JpaRepository<?, ?> 
  extends JpaRepositoryFactoryBean<T> {

  protected RepositoryFactorySupport getRepositoryFactory(…) {
    return new MyRepositoryFactory(…);

  private static class MyRepositoryFactory extends JpaRepositoryFactory{

    public MyRepositoryImpl getTargetRepository(…) {
      return new MyRepositoryImpl(…);

    public Class<? extends RepositorySupport> getRepositoryClass() {
      return MyRepositoryImpl.class;

Finally you can either declare beans of the custom factory directly or use the factory-class attribute of the Spring namespace to tell the repository infrastructure to use your custom factory implementation.

Example 1.17. Using the custom factory with the namespace

<repositories base-package="com.acme.repository" 
  factory-class="com.acme.MyRepositoryFactoryBean" />

Chapter 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 tha 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.

2.2. 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 2.2. 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 Section, “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
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
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


In and NotIn also take any subclass of Collection as parameter as well as arrays or varargs.

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 2.3. 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 2.4. 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 2.5. 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 2.6. 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);

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 2.7. 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 ???. 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 2.8. 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;

2.3. 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 readAll method will return all entities that match the specification:
List<T> readAll(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 2.9. Specifications for a Customer

public class CustomerSpecs {

  public static Specification<Customer> isLongTermCustomer() {
    return new Specification<Customer>() {
      Predicate toPredicate(Root<T> 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>() {
      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. 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 2.10. 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 2.11. Combined Specifications

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

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 2.12. 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 2.13. 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.readAll()) {

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 2.14. 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. Auditing

Most applications will require some form of auditability to track when an entity was created or modified and by whom. Spring Data JPA provides facilities to add this audit information to an entity transparently by AOP means. To take part in this functionality your domain classes must implement a more advanced interface:

Example 2.15. Auditable interface

public interface Auditable<U, ID extends Serializable>
        extends Persistable<ID> {

    U getCreatedBy();

    void setCreatedBy(U createdBy);

    DateTime getCreatedDate();

    void setCreated(Date creationDate);

    U getLastModifiedBy();

    void setLastModifiedBy(U lastModifiedBy);

    DateTime getLastModifiedDate();

    void setLastModified(Date lastModifiedDate);

As you can see the modifying entity itself only has to be an entity. Mostly this will be some sort of User entity, so we chose U as parameter type.


To minimize boilerplate code Spring Data JPA offers AbstractPersistable and AbstractAuditable base classes that implement and pre-configure entities. Thus you can decide to only implement the interface or enjoy more sophisticated support by extending the base class.

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 2.16. 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 2.17. 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 2.18. 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.

2.6. Miscellaneous

2.6.1. 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 2.19. Using MergingPersistenceUnitmanager

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

Part II. Appendix

Appendix A. Namespace reference

A.1. The <repositories /> element

The <repositories /> element acts as container for <repository /> elements or can be left empty to trigger auto detection[1] of repository instances. Attributes defined for <repositories /> act are propagated to contained <repository /> elements but can be overridden of course.

Table A.1. Attributes

base-packageDefines the package to be used to be scanned for repository interfaces extending *Repository (actual interface is determined by specific Spring Data module) in auto detection mode. All packages below the configured package will be scanned, too. In auto configuration mode (no nested <repository /> elements) wildcards are also allowed.
repository-impl-postfixDefines the postfix to autodetect custom repository implementations. Classes whose names end with the configured postfix will be considered as candidates. Defaults to Impl.
query-lookup-strategyDetermines the strategy to be used to create finder queries. See ??? for details. Defaults to create-if-not-found.

A.2. The <repository /> element

The <repository /> element can contain all attributes of <repositories /> except base-package. This will result in overriding the values configured in the surrounding <repositories /> element. Thus here we will only document extended attributes.

Table A.2. Attributes

idDefines the id of the bean the repository instance will be registered under as well as the repository interface name.
custom-impl-refDefines a reference to a custom repository implementation bean.

[1] see ???

Appendix B. Frequently asked questions

B.1. Common


I'd like to get more detailed logging information on what methods are called inside JpaRepository, e.g. How can I gain them?

You can make use of CustomizableTraceInterceptor provided by Spring:

<bean id="customizableTraceInterceptor" class="
  <property name="enterMessage" value="Entering $[methodName]($[arguments])"/>
  <property name="exitMessage" value="Leaving $[methodName](): $[returnValue]"/>

  <aop:advisor advice-ref="customizableTraceInterceptor"
    pointcut="execution(public * org.sfw.data.jpa.repository.JpaRepository+.*(..))"/>

B.2. Infrastructure


Currently I have implemented a repository layer based on HibernateDaoSupport. I create a SessionFactory by using Spring's AnnotationSessionFactoryBean. How do I get Spring Data repositories working in this environment?

You have to replace AnnotationSessionFactoryBean with the LocalContainerEntityManagerFactoryBean. Supposed you have registered it under entityManagerFactory you can reference it in you repositories based on HibernateDaoSupport as follows:

Example B.1. Looking up a SessionFactory from an HibernateEntityManagerFactory

<bean class="com.acme.YourDaoBasedOnHibernateDaoSupport">
  <property name="sessionFactory">
    <bean factory-bean="entityManagerFactory"
      factory-method="getSessionFactory" />

B.3. Auditing


I want to use Spring Data JPA auditing capabilities but have my database already set up to set modification and creation date on entities. How to prevent Spring Data from setting the date programmatically.

Just use the set-dates attribute of the auditing namespace element to false.




Aspect oriented programming


Commons DBCP

Commons DataBase Connection Pools - Library of the Apache foundation offering pooling implementations of the DataSource interface.


Create, Read, Update, Delete - Basic persistence operations



Data Access Object - Pattern to separate persisting logic from the object to be persisted

Dependency Injection

Pattern to hand a component's dependency to the component from outside, freeing the component to lookup the dependant itself. For more information see http://en.wikipedia.org/wiki/Dependency_Injection.



Object relational mapper implementing JPA - http://www.eclipselink.org



Object relational mapper implementing JPA - http://www.hibernate.org



Java Persistence Api



Java application framework - http://www.springframework.org