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Table of Contents

Preface

The Spring Data for Apache Solr project applies core Spring concepts to the development of solutions using the Apache Solr Search Engine. We provide a "template" as a high-level abstraction for storing and querying documents. You will notice similarities to the mongodb support in the Spring Framework.

1. Project Metadata

2. Requirements

Requires Java 8 runtime and Apache Solr 6.5. Preferably the latest 6.5.x version.

<dependency>
  <groupId>org.apache.solr</groupId>
  <artifactId>solr-solrj</artifactId>
  <version>${solr.version}</version>
</dependency>

3. New & Noteworthy

3.1. What’s new in Spring Data for Apache Solr 2.1

  • Autoselect Solr core using SolrTemplate.

  • Assert upwards compatibility with Apache Solr 6 (incl. 6.3).

  • Support for combined Facet and Highlight Query.

  • Allow reading single valued multivalue fields into non collection property.

  • Use native SolrJ schema api.

3.2. What’s new in Spring Data for Apache Solr 2.0

  • Upgrade to Apache Solr 5.

  • Support RequestMethod when querying.

3.3. What’s new in Spring Data for Apache Solr 1.5

3.4. What’s new in Spring Data for Apache Solr 1.4

  • Upgraded to recent Solr 4.10.x distribution (requires Java 7).

  • Add support for Realtime Get.

  • Get Field Stats (max, min, sum, count, mean, missing, stddev and distinct calculations).

  • Use @Score to automatically add projection on document score (See: Special Fields).

4. Working with Spring Data Repositories

The goal of Spring Data repository abstraction is to significantly reduce the amount of boilerplate code required to implement data access layers for various persistence stores.

Spring Data repository documentation and your module

This chapter explains the core concepts and interfaces of Spring Data repositories. The information in this chapter is pulled from the Spring Data Commons module. It uses the configuration and code samples for the Java Persistence API (JPA) module. Adapt the XML namespace declaration and the types to be extended to the equivalents of the particular module that you are using. Namespace reference covers XML configuration which is supported across all Spring Data modules supporting the repository API, Repository query keywords covers the query method keywords supported by the repository abstraction in general. For detailed information on the specific features of your module, consult the chapter on that module of this document.

4.1. Core concepts

The central interface in Spring Data repository abstraction is Repository (probably not that much of a surprise). It takes the domain class to manage as well as the id type of the domain class as type arguments. This interface acts primarily as a marker interface to capture the types to work with and to help you to discover interfaces that extend this one. The CrudRepository provides sophisticated CRUD functionality for the entity class that is being managed.

Example 1. CrudRepository interface
public interface CrudRepository<T, ID extends Serializable>
    extends Repository<T, ID> {

    <S extends T> S save(S entity); (1)

    T findOne(ID primaryKey);       (2)

    Iterable<T> findAll();          (3)

    Long count();                   (4)

    void delete(T entity);          (5)

    boolean exists(ID primaryKey);  (6)

    // … more functionality omitted.
}
1 Saves the given entity.
2 Returns the entity identified by the given id.
3 Returns all entities.
4 Returns the number of entities.
5 Deletes the given entity.
6 Indicates whether an entity with the given id exists.
We also provide persistence technology-specific abstractions like e.g. JpaRepository or MongoRepository. Those interfaces extend CrudRepository and expose the capabilities of the underlying persistence technology in addition to the rather generic persistence technology-agnostic interfaces like e.g. CrudRepository.

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

Example 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));

In addition to query methods, query derivation for both count and delete queries, is available.

Example 3. Derived Count Query
public interface UserRepository extends CrudRepository<User, Long> {

  Long countByLastname(String lastname);
}
Example 4. Derived Delete Query
public interface UserRepository extends CrudRepository<User, Long> {

  Long deleteByLastname(String lastname);

  List<User> removeByLastname(String lastname);

}

4.2. Query methods

Standard CRUD functionality repositories usually have queries on the underlying datastore. With Spring Data, declaring those queries becomes a four-step process:

  1. Declare an interface extending Repository or one of its subinterfaces and type it to the domain class and ID type that it will handle.

    interface PersonRepository extends Repository<Person, Long> { … }

  2. Declare query methods on the interface.

    interface PersonRepository extends Repository<Person, Long> {
  List<Person> findByLastname(String lastname);
}

  3. Set up Spring to create proxy instances for those interfaces. Either via JavaConfig:

    import org.springframework.data.jpa.repository.config.EnableJpaRepositories;

@EnableJpaRepositories
class Config {}

    or via XML configuration:

    <?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:jpa="http://www.springframework.org/schema/data/jpa"
   xsi:schemaLocation="http://www.springframework.org/schema/beans
     http://www.springframework.org/schema/beans/spring-beans.xsd
     http://www.springframework.org/schema/data/jpa
     http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">

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

</beans>

    The JPA namespace is used in this example. If you are using the repository abstraction for any other store, you need to change this to the appropriate namespace declaration of your store module which should be exchanging jpa in favor of, for example, mongodb.

    Also, note that the JavaConfig variant doesn’t configure a package explictly as the package of the annotated class is used by default. To customize the package to scan use one of the basePackage… attribute of the data-store specific repository @Enable…-annotation.

  4. Get the repository instance injected and use it.

    public class SomeClient {

  @Autowired
  private PersonRepository repository;

  public void doSomething() {
    List<Person> persons = repository.findByLastname("Matthews");
  }
}

The sections that follow explain each step in detail.

4.3. Defining repository interfaces

As a first step you define a domain class-specific repository interface. The interface must 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.

4.3.1. Fine-tuning repository definition

Typically, your repository interface will extend Repository, CrudRepository or PagingAndSortingRepository. Alternatively, if you do not want to extend Spring Data interfaces, you can also annotate your repository interface with @RepositoryDefinition. Extending CrudRepository exposes a complete set of methods to manipulate your entities. If you prefer to be selective about the methods being exposed, simply copy the ones you want to expose from CrudRepository into your domain repository.

This allows you to define your own abstractions on top of the provided Spring Data Repositories functionality.
Example 5. Selectively exposing CRUD methods
@NoRepositoryBean
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 this first step you defined a common base interface for all your domain repositories and exposed findOne(…) as well as save(…).These methods will be routed into the base repository implementation of the store of your choice provided by Spring Data ,e.g. in the case if JPA SimpleJpaRepository, because they are matching the method signatures in CrudRepository. So the UserRepository will now be able to save users, and find single ones by id, as well as triggering a query to find Users by their email address.

Note, that the intermediate repository interface is annotated with @NoRepositoryBean. Make sure you add that annotation to all repository interfaces that Spring Data should not create instances for at runtime.

4.3.2. Using Repositories with multiple Spring Data modules

Using a unique Spring Data module in your application makes things simple hence, all repository interfaces in the defined scope are bound to the Spring Data module. Sometimes applications require using more than one Spring Data module. In such case, it’s required for a repository definition to distinguish between persistence technologies. Spring Data enters strict repository configuration mode because it detects multiple repository factories on the class path. Strict configuration requires details on the repository or the domain class to decide about Spring Data module binding for a repository definition:

  1. If the repository definition extends the module-specific repository, then it’s a valid candidate for the particular Spring Data module.

  2. If the domain class is annotated with the module-specific type annotation, then it’s a valid candidate for the particular Spring Data module. Spring Data modules accept either 3rd party annotations (such as JPA’s @Entity) or provide own annotations such as @Document for Spring Data MongoDB/Spring Data Elasticsearch.

Example 6. Repository definitions using Module-specific Interfaces
interface MyRepository extends JpaRepository<User, Long> { }

@NoRepositoryBean
interface MyBaseRepository<T, ID extends Serializable> extends JpaRepository<T, ID> {
  …
}

interface UserRepository extends MyBaseRepository<User, Long> {
  …
}

MyRepository and UserRepository extend JpaRepository in their type hierarchy. They are valid candidates for the Spring Data JPA module.

Example 7. Repository definitions using generic Interfaces
interface AmbiguousRepository extends Repository<User, Long> {
 …
}

@NoRepositoryBean
interface MyBaseRepository<T, ID extends Serializable> extends CrudRepository<T, ID> {
  …
}

interface AmbiguousUserRepository extends MyBaseRepository<User, Long> {
  …
}

AmbiguousRepository and AmbiguousUserRepository extend only Repository and CrudRepository in their type hierarchy. While this is perfectly fine using a unique Spring Data module, multiple modules cannot distinguish to which particular Spring Data these repositories should be bound.

Example 8. Repository definitions using Domain Classes with Annotations
interface PersonRepository extends Repository<Person, Long> {
 …
}

@Entity
public class Person {
  …
}

interface UserRepository extends Repository<User, Long> {
 …
}

@Document
public class User {
  …
}

PersonRepository references Person which is annotated with the JPA annotation @Entity so this repository clearly belongs to Spring Data JPA. UserRepository uses User annotated with Spring Data MongoDB’s @Document annotation.

Example 9. Repository definitions using Domain Classes with mixed Annotations
interface JpaPersonRepository extends Repository<Person, Long> {
 …
}

interface MongoDBPersonRepository extends Repository<Person, Long> {
 …
}

@Entity
@Document
public class Person {
  …
}

This example shows a domain class using both JPA and Spring Data MongoDB annotations. It defines two repositories, JpaPersonRepository and MongoDBPersonRepository. One is intended for JPA and the other for MongoDB usage. Spring Data is no longer able to tell the repositories apart which leads to undefined behavior.

Repository type details and identifying domain class annotations are used for strict repository configuration identify repository candidates for a particular Spring Data module. Using multiple persistence technology-specific annotations on the same domain type is possible to reuse domain types across multiple persistence technologies, but then Spring Data is no longer able to determine a unique module to bind the repository.

The last way to distinguish repositories is scoping repository base packages. Base packages define the starting points for scanning for repository interface definitions which implies to have repository definitions located in the appropriate packages. By default, annotation-driven configuration uses the package of the configuration class. The base package in XML-based configuration is mandatory.

Example 10. Annotation-driven configuration of base packages
@EnableJpaRepositories(basePackages = "com.acme.repositories.jpa")
@EnableMongoRepositories(basePackages = "com.acme.repositories.mongo")
interface Configuration { }

4.4. Defining query methods

The repository proxy has two ways to derive a store-specific query from the method name. It can derive the query from the method name directly, or by using a manually defined query. Available options depend on the actual store. However, there’s got to be a strategy that decides what actual query is created. Let’s have a look at the available options.

4.4.1. Query lookup strategies

The following strategies are available for the repository infrastructure to resolve the query. You can configure the strategy at the namespace through the query-lookup-strategy attribute in case of XML configuration or via the queryLookupStrategy attribute of the Enable${store}Repositories annotation in case of Java config. Some strategies may not be supported for particular datastores.

  • CREATE attempts to construct a store-specific query from the query method 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 Query creation.

  • USE_DECLARED_QUERY tries to find a declared query and will throw an exception in case it can’t find one. The query can be defined by an annotation somewhere or declared by other means. Consult the documentation of the specific store to find available options for that store. If the repository infrastructure does not find a declared query for the method at bootstrap time, it fails.

  • CREATE_IF_NOT_FOUND (default) combines CREATE and USE_DECLARED_QUERY. It looks up a declared query first, and if no declared query is found, it creates a custom method name-based query. This is the default lookup strategy and thus will be used if you do not configure anything explicitly. It allows quick query definition by method names but also custom-tuning of these queries by introducing declared queries as needed.

4.4.2. Query creation

The query builder mechanism built into Spring Data repository infrastructure is useful for building constraining queries over entities of the repository. The mechanism strips the prefixes find…By, read…By, query…By, count…By, and get…By from the method and starts parsing the rest of it. The introducing clause can contain further expressions such as a Distinct to set a distinct flag on the query to be created. However, the first By acts as delimiter to indicate the start of the actual criteria. At a very basic level you can define conditions on entity properties and concatenate them with And and Or.

Example 11. Query creation from method names
public interface PersonRepository extends Repository<User, Long> {

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

  // Enables the distinct flag for the query
  List<Person> findDistinctPeopleByLastnameOrFirstname(String lastname, String firstname);
  List<Person> findPeopleDistinctByLastnameOrFirstname(String lastname, String firstname);

  // Enabling ignoring case for an individual property
  List<Person> findByLastnameIgnoreCase(String lastname);
  // Enabling ignoring case for all suitable properties
  List<Person> findByLastnameAndFirstnameAllIgnoreCase(String lastname, String firstname);

  // Enabling static ORDER BY for a query
  List<Person> findByLastnameOrderByFirstnameAsc(String lastname);
  List<Person> findByLastnameOrderByFirstnameDesc(String lastname);
}

The actual result of parsing the method depends on the persistence store for which you create the query. However, there are some general things to notice.

  • The expressions are usually property traversals combined with operators that can be concatenated. You can combine property expressions with AND and OR. You also get support for operators such as Between, LessThan, GreaterThan, Like for the property expressions. The supported operators can vary by datastore, so consult the appropriate part of your reference documentation.

  • The method parser supports setting an IgnoreCase flag for individual properties (for example, findByLastnameIgnoreCase(…)) or for all properties of a type that support ignoring case (usually String instances, for example, findByLastnameAndFirstnameAllIgnoreCase(…)). Whether ignoring cases is supported may vary by store, so consult the relevant sections in the reference documentation for the store-specific query method.

  • You can apply static ordering by appending an OrderBy clause to the query method that references a property and by providing a sorting direction (Asc or Desc). To create a query method that supports dynamic sorting, see Special parameter handling.

4.4.3. Property expressions

Property expressions can refer only to a direct property of the managed entity, as shown in the preceding example. At query creation time you already make sure that the parsed property is a property of the managed domain class. However, you can also define constraints by traversing nested properties. Assume a Person has an Address with a ZipCode. In that case a method name of

List<Person> findByAddressZipCode(ZipCode zipCode);

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

Although this should work for most cases, it is possible for the algorithm to select the wrong property. Suppose the Person class has an addressZip property as well. The 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);

As we treat underscore as a reserved character we strongly advise to follow standard Java naming conventions (i.e. not using underscores in property names but camel case instead).

4.4.4. Special parameter handling

To handle parameters in your query you simply define method parameters as already seen in the examples above. Besides that the infrastructure will recognize certain specific types like Pageable and Sort to apply pagination and sorting to your queries dynamically.

Example 12. Using Pageable, Slice and Sort in query methods
Page<User> findByLastname(String lastname, Pageable pageable);

Slice<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 an org.springframework.data.domain.Pageable instance to the query method to dynamically add paging to your statically defined query. A Page knows about the total number of elements and pages available. It does so by the infrastructure triggering a count query to calculate the overall number. As this might be expensive depending on the store used, Slice can be used as return instead. A Slice only knows about whether there’s a next Slice available which might be just sufficient when walking through a larger result set.

Sorting options are handled through the Pageable instance too. If you only need sorting, simply add an org.springframework.data.domain.Sort parameter to your method. As you also can see, simply returning a List is possible as well. In this case the additional metadata required to build the actual Page instance will not be created (which in turn means that the additional count query that would have been necessary not being issued) but rather simply restricts the query to look up only the given range of entities.

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

4.4.5. Limiting query results

The results of query methods can be limited via the keywords first or top, which can be used interchangeably. An optional numeric value can be appended to top/first to specify the maximum result size to be returned. If the number is left out, a result size of 1 is assumed.

Example 13. Limiting the result size of a query with Top and First
User findFirstByOrderByLastnameAsc();

User findTopByOrderByAgeDesc();

Page<User> queryFirst10ByLastname(String lastname, Pageable pageable);

Slice<User> findTop3ByLastname(String lastname, Pageable pageable);

List<User> findFirst10ByLastname(String lastname, Sort sort);

List<User> findTop10ByLastname(String lastname, Pageable pageable);

The limiting expressions also support the Distinct keyword. Also, for the queries limiting the result set to one instance, wrapping the result into an Optional is supported.

If pagination or slicing is applied to a limiting query pagination (and the calculation of the number of pages available) then it is applied within the limited result.

Note that limiting the results in combination with dynamic sorting via a Sort parameter allows to express query methods for the 'K' smallest as well as for the 'K' biggest elements.

4.4.6. Streaming query results

The results of query methods can be processed incrementally by using a Java 8 Stream<T> as return type. Instead of simply wrapping the query results in a Stream data store specific methods are used to perform the streaming.

Example 14. Stream the result of a query with Java 8 Stream<T>
@Query("select u from User u")
Stream<User> findAllByCustomQueryAndStream();

Stream<User> readAllByFirstnameNotNull();

@Query("select u from User u")
Stream<User> streamAllPaged(Pageable pageable);
A Stream potentially wraps underlying data store specific resources and must therefore be closed after usage. You can either manually close the Stream using the close() method or by using a Java 7 try-with-resources block.
Example 15. Working with a Stream<T> result in a try-with-resources block
try (Stream<User> stream = repository.findAllByCustomQueryAndStream()) {
  stream.forEach(…);
}
Not all Spring Data modules currently support Stream<T> as a return type.

4.4.7. Async query results

Repository queries can be executed asynchronously using Spring’s asynchronous method execution capability. This means the method will return immediately upon invocation and the actual query execution will occur in a task that has been submitted to a Spring TaskExecutor.

@Async
Future<User> findByFirstname(String firstname);               (1)

@Async
CompletableFuture<User> findOneByFirstname(String firstname); (2)

@Async
ListenableFuture<User> findOneByLastname(String lastname);    (3)
1 Use java.util.concurrent.Future as return type.
2 Use a Java 8 java.util.concurrent.CompletableFuture as return type.
3 Use a org.springframework.util.concurrent.ListenableFuture as return type.

4.5. Creating repository instances

In this section you create instances and bean definitions for the repository interfaces defined. One way to do so is using the Spring namespace that is shipped with each Spring Data module that supports the repository mechanism although we generally recommend to use the Java-Config style configuration.

4.5.1. XML configuration

Each Spring Data module includes a repositories element that allows you to simply define a base package that Spring scans for you.

Example 16. Enabling Spring Data repositories via XML
<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns:beans="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns="http://www.springframework.org/schema/data/jpa"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/data/jpa
    http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">

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

</beans:beans>

In the preceding example, Spring is instructed to scan com.acme.repositories and all its sub-packages for interfaces extending Repository or one of its sub-interfaces. For each interface found, the infrastructure registers the persistence technology-specific FactoryBean to create the appropriate proxies that handle invocations of the query methods. Each bean is 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 wildcards, so that you can define a pattern of scanned packages.

Using filters

By default the infrastructure picks up every interface extending the persistence technology-specific Repository sub-interface located under the configured base package and creates a bean instance for it. However, you might want more fine-grained control over which interfaces bean instances get created for. To do this you use <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.

For example, to exclude certain interfaces from instantiation as repository, you could use the following configuration:

Example 17. Using exclude-filter element
<repositories base-package="com.acme.repositories">
  <context:exclude-filter type="regex" expression=".*SomeRepository" />
</repositories>

This example excludes all interfaces ending in SomeRepository from being instantiated.

4.5.2. JavaConfig

The repository infrastructure can also be triggered using a store-specific @Enable${store}Repositories annotation on a JavaConfig class. For an introduction into Java-based configuration of the Spring container, see the reference documentation.[1]

A sample configuration to enable Spring Data repositories looks something like this.

Example 18. Sample annotation based repository configuration
@Configuration
@EnableJpaRepositories("com.acme.repositories")
class ApplicationConfiguration {

  @Bean
  public EntityManagerFactory entityManagerFactory() {
    // …
  }
}
The sample uses the JPA-specific annotation, which you would change according to the store module you actually use. The same applies to the definition of the EntityManagerFactory bean. Consult the sections covering the store-specific configuration.

4.5.3. Standalone usage

You can also use the repository infrastructure outside of a Spring container, e.g. in CDI environments. You still need some Spring libraries in your classpath, but generally you can set up repositories programmatically as well. The Spring Data modules that provide repository support ship a persistence technology-specific RepositoryFactory that you can use as follows.

Example 19. Standalone usage of repository factory
RepositoryFactorySupport factory = … // Instantiate factory here
UserRepository repository = factory.getRepository(UserRepository.class);

4.6. Custom implementations for Spring Data repositories

Often it is necessary to provide a custom implementation for a few repository methods. Spring Data repositories easily allow you to provide custom repository code and integrate it with generic CRUD abstraction and query method functionality.

4.6.1. Adding custom behavior to single repositories

To enrich a repository with custom functionality you first define an interface and an implementation for the custom functionality. Use the repository interface you provided to extend the custom interface.

Example 20. Interface for custom repository functionality
interface UserRepositoryCustom {
  public void someCustomMethod(User user);
}
Example 21. Implementation of custom repository functionality
class UserRepositoryImpl implements UserRepositoryCustom {

  public void someCustomMethod(User user) {
    // Your custom implementation
  }
}
The most important bit for the class to be found is the Impl postfix of the name on it compared to the core repository interface (see below).

The implementation itself does not depend on Spring Data and can be a regular Spring bean. So you can use standard dependency injection behavior to inject references to other beans like a JdbcTemplate, take part in aspects, and so on.

Example 22. Changes to the your basic repository interface
interface UserRepository extends CrudRepository<User, Long>, UserRepositoryCustom {

  // Declare query methods here
}

Let your standard repository interface extend the custom one. Doing so combines the CRUD and custom functionality and makes it available to clients.

Configuration

If you use namespace configuration, the repository infrastructure tries to autodetect custom implementations by scanning for classes below the package we found a repository in. These classes need to follow the naming convention of appending the namespace element’s attribute repository-impl-postfix to the found repository interface name. This postfix defaults to Impl.

Example 23. Configuration example
<repositories base-package="com.acme.repository" />

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

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

Resolution of ambiguity

If multiple implementations with matching class names get found in different packages, Spring Data uses the bean names to identify the correct one to use.

Given the following two custom implementations for the UserRepository introduced above the first implementation will get picked. Its bean name is userRepositoryImpl matches that of the repository interface (userRepository) plus the postfix Impl.

Example 24. Resolution of amibiguous implementations
package com.acme.impl.one;

class UserRepositoryImpl implements UserRepositoryCustom {

  // Your custom implementation
}
package com.acme.impl.two;

@Component("specialCustomImpl")
class UserRepositoryImpl implements UserRepositoryCustom {

  // Your custom implementation
}

If you annotate the UserRepository interface with @Component("specialCustom") the bean name plus Impl matches the one defined for the repository implementation in com.acme.impl.two and it will be picked instead of the first one.

Manual wiring

The approach just shown works well if your custom implementation uses annotation-based configuration and autowiring only, as it will be treated as any other Spring bean. If your custom implementation bean needs special wiring, you simply declare the bean and name it after the conventions just described. The infrastructure will then refer to the manually defined bean definition by name instead of creating one itself.

Example 25. Manual wiring of custom implementations
<repositories base-package="com.acme.repository" />

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

4.6.2. Adding custom behavior to all repositories

The preceding approach is not feasible when you want to add a single method to all your repository interfaces. To add custom behavior to all repositories, you first add an intermediate interface to declare the shared behavior.

Example 26. An interface declaring custom shared behavior
@NoRepositoryBean
public interface MyRepository<T, ID extends Serializable>
  extends PagingAndSortingRepository<T, ID> {

  void sharedCustomMethod(ID id);
}

Now your individual repository interfaces will extend this intermediate interface instead of the Repository interface to include the functionality declared. Next, create an implementation of the intermediate interface that extends the persistence technology-specific repository base class. This class will then act as a custom base class for the repository proxies.

Example 27. Custom repository base class
public class MyRepositoryImpl<T, ID extends Serializable>
  extends SimpleJpaRepository<T, ID> implements MyRepository<T, ID> {

  private final EntityManager entityManager;

  public MyRepositoryImpl(JpaEntityInformation entityInformation,
                          EntityManager entityManager) {
    super(entityInformation, entityManager);

    // Keep the EntityManager around to used from the newly introduced methods.
    this.entityManager = entityManager;
  }

  public void sharedCustomMethod(ID id) {
    // implementation goes here
  }
}
The class needs to have a constructor of the super class which the store-specific repository factory implementation is using. In case the repository base class has multiple constructors, override the one taking an EntityInformation plus a store specific infrastructure object (e.g. an EntityManager or a template class).

The default behavior of the Spring <repositories /> namespace is to provide an implementation for all interfaces that fall under the base-package. This means that if left in its current state, an implementation instance of MyRepository will be created by Spring. This is of course not desired as it is just supposed to act as an intermediary between Repository and the actual repository interfaces you want to define for each entity. To exclude an interface that extends Repository from being instantiated as a repository instance, you can either annotate it with @NoRepositoryBean (as seen above) or move it outside of the configured base-package.

The final step is to make the Spring Data infrastructure aware of the customized repository base class. In JavaConfig this is achieved by using the repositoryBaseClass attribute of the @Enable…Repositories annotation:

Example 28. Configuring a custom repository base class using JavaConfig
@Configuration
@EnableJpaRepositories(repositoryBaseClass = MyRepositoryImpl.class)
class ApplicationConfiguration { … }

A corresponding attribute is available in the XML namespace.

Example 29. Configuring a custom repository base class using XML
<repositories base-package="com.acme.repository"
     base-class="….MyRepositoryImpl" />

4.7. Publishing events from aggregate roots

Entities managed by repositories are aggregate roots. In a Domain-Driven Design application, these aggregate roots usually publish domain events. Spring Data provides an annotation @DomainEvents you can use on a method of your aggregate root to make that publication as easy as possible.

Example 30. Exposing domain events from an aggregate root
class AnAggregateRoot {

    @DomainEvents (1)
    Collection<Object> domainEvents() {
        // … return events you want to get published here
    }

    @AfterDomainEventsPublication (2)
    void callbackMethod() {
       // … potentially clean up domain events list
    }
}
1 The method using @DomainEvents can either return a single event instance or a collection of events. It must not take any arguments.
2 After all events have been published, a method annotated with @AfterDomainEventsPublication. It e.g. can be used to potentially clean the list of events to be published.

The methods will be called every time one of a Spring Data repository’s save(…) methods is called.

4.8. Spring Data extensions

This section documents a set of Spring Data extensions that enable Spring Data usage in a variety of contexts. Currently most of the integration is targeted towards Spring MVC.

4.8.1. Querydsl Extension

Querydsl is a framework which enables the construction of statically typed SQL-like queries via its fluent API.

Several Spring Data modules offer integration with Querydsl via QueryDslPredicateExecutor.

Example 31. QueryDslPredicateExecutor interface
public interface QueryDslPredicateExecutor<T> {

    T findOne(Predicate predicate);             (1)

    Iterable<T> findAll(Predicate predicate);   (2)

    long count(Predicate predicate);            (3)

    boolean exists(Predicate predicate);        (4)

    // … more functionality omitted.
}
1 Finds and returns a single entity matching the Predicate.
2 Finds and returns all entities matching the Predicate.
3 Returns the number of entities matching the Predicate.
4 Returns if an entity that matches the Predicate exists.

To make use of Querydsl support simply extend QueryDslPredicateExecutor on your repository interface.

Example 32. Querydsl integration on repositories
interface UserRepository extends CrudRepository<User, Long>, QueryDslPredicateExecutor<User> {

}

The above enables to write typesafe queries using Querydsl Predicate s.

Predicate predicate = user.firstname.equalsIgnoreCase("dave")
	.and(user.lastname.startsWithIgnoreCase("mathews"));

userRepository.findAll(predicate);

4.8.2. Web support

This section contains the documentation for the Spring Data web support as it is implemented as of Spring Data Commons in the 1.6 range. As it the newly introduced support changes quite a lot of things we kept the documentation of the former behavior in Legacy web support.

Spring Data modules ships with a variety of web support if the module supports the repository programming model. The web related stuff requires Spring MVC JARs on the classpath, some of them even provide integration with Spring HATEOAS [2]. In general, the integration support is enabled by using the @EnableSpringDataWebSupport annotation in your JavaConfig configuration class.

Example 33. Enabling Spring Data web support
@Configuration
@EnableWebMvc
@EnableSpringDataWebSupport
class WebConfiguration { }

The @EnableSpringDataWebSupport annotation registers a few components we will discuss in a bit. It will also detect Spring HATEOAS on the classpath and register integration components for it as well if present.

Alternatively, if you are using XML configuration, register either SpringDataWebSupport or HateoasAwareSpringDataWebSupport as Spring beans:

Example 34. Enabling Spring Data web support in XML
<bean class="org.springframework.data.web.config.SpringDataWebConfiguration" />

<!-- If you're using Spring HATEOAS as well register this one *instead* of the former -->
<bean class="org.springframework.data.web.config.HateoasAwareSpringDataWebConfiguration" />
Basic web support

The configuration setup shown above will register a few basic components:

  • A DomainClassConverter to enable Spring MVC to resolve instances of repository managed domain classes from request parameters or path variables.

  • HandlerMethodArgumentResolver implementations to let Spring MVC resolve Pageable and Sort instances from request parameters.

DomainClassConverter

The DomainClassConverter allows you to use domain types in your Spring MVC controller method signatures directly, so that you don’t have to manually lookup the instances via the repository:

Example 35. A Spring MVC controller using domain types in method signatures
@Controller
@RequestMapping("/users")
public class UserController {

  @RequestMapping("/{id}")
  public String showUserForm(@PathVariable("id") User user, Model model) {

    model.addAttribute("user", user);
    return "userForm";
  }
}

As you can see the method receives a User instance directly and no further lookup is necessary. The instance can be resolved by letting Spring MVC convert the path variable into the id type of the domain class first and eventually access the instance through calling findOne(…) on the repository instance registered for the domain type.

Currently the repository has to implement CrudRepository to be eligible to be discovered for conversion.
HandlerMethodArgumentResolvers for Pageable and Sort

The configuration snippet above also registers a PageableHandlerMethodArgumentResolver as well as an instance of SortHandlerMethodArgumentResolver. The registration enables Pageable and Sort being valid controller method arguments

Example 36. Using Pageable as controller method argument
@Controller
@RequestMapping("/users")
public class UserController {

  @Autowired UserRepository repository;

  @RequestMapping
  public String showUsers(Model model, Pageable pageable) {

    model.addAttribute("users", repository.findAll(pageable));
    return "users";
  }
}

This method signature will cause Spring MVC try to derive a Pageable instance from the request parameters using the following default configuration:

Table 1. Request parameters evaluated for Pageable instances

page

Page you want to retrieve, 0 indexed and defaults to 0.

size

Size of the page you want to retrieve, defaults to 20.

sort

Properties that should be sorted by in the format property,property(,ASC|DESC). Default sort direction is ascending. Use multiple sort parameters if you want to switch directions, e.g. ?sort=firstname&sort=lastname,asc.

To customize this behavior register a bean implementing the interface PageableHandlerMethodArgumentResolverCustomizer or SortHandlerMethodArgumentResolverCustomizer respectively. It’s customize() method will get called allowing you to change settings. Like in the following example.

@Bean SortHandlerMethodArgumentResolverCustomizer sortCustomizer() {
    return s -> s.setPropertyDelimiter("<-->");
}

If setting the properties of an existing MethodArgumentResolver isn’t sufficient for your purpose extend either SpringDataWebConfiguration or the HATEOAS-enabled equivalent and override the pageableResolver() or sortResolver() methods and import your customized configuration file instead of using the @Enable-annotation.

In case you need multiple Pageable or Sort instances to be resolved from the request (for multiple tables, for example) you can use Spring’s @Qualifier annotation to distinguish one from another. The request parameters then have to be prefixed with ${qualifier}_. So for a method signature like this:

public String showUsers(Model model,
      @Qualifier("foo") Pageable first,
      @Qualifier("bar") Pageable second) { … }

you have to populate foo_page and bar_page etc.

The default Pageable handed into the method is equivalent to a new PageRequest(0, 20) but can be customized using the @PageableDefaults annotation on the Pageable parameter.

Hypermedia support for Pageables

Spring HATEOAS ships with a representation model class PagedResources that allows enriching the content of a Page instance with the necessary Page metadata as well as links to let the clients easily navigate the pages. The conversion of a Page to a PagedResources is done by an implementation of the Spring HATEOAS ResourceAssembler interface, the PagedResourcesAssembler.

Example 37. Using a PagedResourcesAssembler as controller method argument
@Controller
class PersonController {

  @Autowired PersonRepository repository;

  @RequestMapping(value = "/persons", method = RequestMethod.GET)
  HttpEntity<PagedResources<Person>> persons(Pageable pageable,
    PagedResourcesAssembler assembler) {

    Page<Person> persons = repository.findAll(pageable);
    return new ResponseEntity<>(assembler.toResources(persons), HttpStatus.OK);
  }
}

Enabling the configuration as shown above allows the PagedResourcesAssembler to be used as controller method argument. Calling toResources(…) on it will cause the following:

  • The content of the Page will become the content of the PagedResources instance.

  • The PagedResources will get a PageMetadata instance attached populated with information form the Page and the underlying PageRequest.

  • The PagedResources gets prev and next links attached depending on the page’s state. The links will point to the URI the method invoked is mapped to. The pagination parameters added to the method will match the setup of the PageableHandlerMethodArgumentResolver to make sure the links can be resolved later on.

Assume we have 30 Person instances in the database. You can now trigger a request GET http://localhost:8080/persons and you’ll see something similar to this:

{ "links" : [ { "rel" : "next",
                "href" : "http://localhost:8080/persons?page=1&size=20 }
  ],
  "content" : [
     … // 20 Person instances rendered here
  ],
  "pageMetadata" : {
    "size" : 20,
    "totalElements" : 30,
    "totalPages" : 2,
    "number" : 0
  }
}

You see that the assembler produced the correct URI and also picks up the default configuration present to resolve the parameters into a Pageable for an upcoming request. This means, if you change that configuration, the links will automatically adhere to the change. By default the assembler points to the controller method it was invoked in but that can be customized by handing in a custom Link to be used as base to build the pagination links to overloads of the PagedResourcesAssembler.toResource(…) method.

Querydsl web support

For those stores having QueryDSL integration it is possible to derive queries from the attributes contained in a Request query string.

This means that given the User object from previous samples a query string

?firstname=Dave&lastname=Matthews

can be resolved to

QUser.user.firstname.eq("Dave").and(QUser.user.lastname.eq("Matthews"))

using the QuerydslPredicateArgumentResolver.

The feature will be automatically enabled along @EnableSpringDataWebSupport when Querydsl is found on the classpath.

Adding a @QuerydslPredicate to the method signature will provide a ready to use Predicate which can be executed via the QueryDslPredicateExecutor.

Type information is typically resolved from the methods return type. Since those information does not necessarily match the domain type it might be a good idea to use the root attribute of QuerydslPredicate. 
@Controller
class UserController {

  @Autowired UserRepository repository;

  @RequestMapping(value = "/", method = RequestMethod.GET)
  String index(Model model, @QuerydslPredicate(root = User.class) Predicate predicate,    (1)
          Pageable pageable, @RequestParam MultiValueMap<String, String> parameters) {

    model.addAttribute("users", repository.findAll(predicate, pageable));

    return "index";
  }
}
1 Resolve query string arguments to matching Predicate for User.

The default binding is as follows:

  • Object on simple properties as eq.

  • Object on collection like properties as contains.

  • Collection on simple properties as in.

Those bindings can be customized via the bindings attribute of @QuerydslPredicate or by making use of Java 8 default methods adding the QuerydslBinderCustomizer to the repository interface.

interface UserRepository extends CrudRepository<User, String>,
                                 QueryDslPredicateExecutor<User>,                (1)
                                 QuerydslBinderCustomizer<QUser> {               (2)

  @Override
  default public void customize(QuerydslBindings bindings, QUser user) {

    bindings.bind(user.username).first((path, value) -> path.contains(value))    (3)
    bindings.bind(String.class)
      .first((StringPath path, String value) -> path.containsIgnoreCase(value)); (4)
    bindings.excluding(user.password);                                           (5)
  }
}
1 QueryDslPredicateExecutor provides access to specific finder methods for Predicate.
2 QuerydslBinderCustomizer defined on the repository interface will be automatically picked up and shortcuts @QuerydslPredicate(bindings=…​).
3 Define the binding for the username property to be a simple contains binding.
4 Define the default binding for String properties to be a case insensitive contains match.
5 Exclude the password property from Predicate resolution.

4.8.3. Repository populators

If you work with the Spring JDBC module, you probably are familiar with the support to populate a DataSource using SQL scripts. A similar abstraction is available on the repositories level, although it does not use SQL as the data definition language because it must be store-independent. Thus the populators support XML (through Spring’s OXM abstraction) and JSON (through Jackson) to define data with which to populate the repositories.

Assume you have a file data.json with the following content:

Example 38. Data defined in JSON
[ { "_class" : "com.acme.Person",
 "firstname" : "Dave",
  "lastname" : "Matthews" },
  { "_class" : "com.acme.Person",
 "firstname" : "Carter",
  "lastname" : "Beauford" } ]

You can easily populate your repositories by using the populator elements of the repository namespace provided in Spring Data Commons. To populate the preceding data to your PersonRepository , do the following:

Example 39. Declaring a Jackson repository populator
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:repository="http://www.springframework.org/schema/data/repository"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/data/repository
    http://www.springframework.org/schema/data/repository/spring-repository.xsd">

  <repository:jackson2-populator locations="classpath:data.json" />

</beans>

This declaration causes the data.json file to be read and deserialized via a Jackson ObjectMapper.

The type to which the JSON object will be unmarshalled to will be determined by inspecting the _class attribute of the JSON document. The infrastructure will eventually select the appropriate repository to handle the object just deserialized.

To rather use XML to define the data the repositories shall be populated with, you can use the unmarshaller-populator element. You configure it to use one of the XML marshaller options Spring OXM provides you with. See the Spring reference documentation for details.

Example 40. Declaring an unmarshalling repository populator (using JAXB)
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:repository="http://www.springframework.org/schema/data/repository"
  xmlns:oxm="http://www.springframework.org/schema/oxm"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/data/repository
    http://www.springframework.org/schema/data/repository/spring-repository.xsd
    http://www.springframework.org/schema/oxm
    http://www.springframework.org/schema/oxm/spring-oxm.xsd">

  <repository:unmarshaller-populator locations="classpath:data.json"
    unmarshaller-ref="unmarshaller" />

  <oxm:jaxb2-marshaller contextPath="com.acme" />

</beans>

4.8.4. Legacy web support

Domain class web binding for Spring MVC

Given you are developing a Spring MVC web application you typically have to resolve domain class ids from URLs. By default your task is to transform that request parameter or URL part into the domain class to hand it to layers below then or execute business logic on the entities directly. This would look something like this:

@Controller
@RequestMapping("/users")
public class UserController {

  private final UserRepository userRepository;

  @Autowired
  public UserController(UserRepository userRepository) {
    Assert.notNull(repository, "Repository must not be null!");
    this.userRepository = userRepository;
  }

  @RequestMapping("/{id}")
  public String showUserForm(@PathVariable("id") Long id, Model model) {

    // Do null check for id
    User user = userRepository.findOne(id);
    // Do null check for user

    model.addAttribute("user", user);
    return "user";
  }
}

First you declare a repository dependency for each controller to look up the entity managed by the controller or repository respectively. Looking up the entity is boilerplate as well, as it’s always a findOne(…) call. Fortunately Spring provides means to register custom components that allow conversion between a String value to an arbitrary type.

PropertyEditors

For Spring versions before 3.0 simple Java PropertyEditors had to be used. To integrate with that, Spring Data offers a DomainClassPropertyEditorRegistrar, which looks up all Spring Data repositories registered in the ApplicationContext and registers a custom PropertyEditor for the managed domain class.

<bean class="….web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
  <property name="webBindingInitializer">
    <bean class="….web.bind.support.ConfigurableWebBindingInitializer">
      <property name="propertyEditorRegistrars">
        <bean class="org.springframework.data.repository.support.DomainClassPropertyEditorRegistrar" />
      </property>
    </bean>
  </property>
</bean>

If you have configured Spring MVC as in the preceding example, you can configure your controller as follows, which reduces a lot of the clutter and boilerplate.

@Controller
@RequestMapping("/users")
public class UserController {

  @RequestMapping("/{id}")
  public String showUserForm(@PathVariable("id") User user, Model model) {

    model.addAttribute("user", user);
    return "userForm";
  }
}

Reference Documentation

5. Solr Repositories

This chapter includes details of the Solr repository implementation.

5.1. Introduction

5.1.1. Spring Namespace

The Spring Data Solr module contains a custom namespace allowing definition of repository beans as well as elements for instantiating a SolrClient .

Using the repositories element looks up Spring Data repositories as described in Creating repository instances .

Example 41. Setting up Solr repositories using Namespace
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:solr="http://www.springframework.org/schema/data/solr"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/data/solr
    http://www.springframework.org/schema/data/solr/spring-solr.xsd">

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

Using the solr-server or embedded-solr-server element registers an instance of SolrClient in the context.

Example 42. HttpSolrClient using Namespace
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:solr="http://www.springframework.org/schema/data/solr"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/data/solr
    http://www.springframework.org/schema/data/solr/spring-solr.xsd">

  <solr:solr-client id="solrClient" url="http://locahost:8983/solr" />
</beans>
Example 43. LBSolrClient using Namespace
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:solr="http://www.springframework.org/schema/data/solr"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/data/solr
    http://www.springframework.org/schema/data/solr/spring-solr.xsd">

  <solr:solr-client id="solrClient" url="http://locahost:8983/solr,http://localhost:8984/solr" />
</beans>
Example 44. EmbeddedSolrServer using Namespace
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:solr="http://www.springframework.org/schema/data/solr"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/data/solr
    http://www.springframework.org/schema/data/solr/spring-solr.xsd">

  <solr:embedded-solr-server id="solrClient" solrHome="classpath:com/acme/solr" />
</beans>

5.1.2. Annotation based configuration

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

Example 45. Spring Data Solr repositories using JavaConfig
@Configuration
@EnableSolrRepositories
class ApplicationConfig {

  @Bean
  public SolrClient solrClient() {
    EmbeddedSolrServerFactory factory = new EmbeddedSolrServerFactory("classpath:com/acme/solr");
    return factory.getSolrServer();
  }

  @Bean
  public SolrOperations solrTemplate() {
    return new SolrTemplate(solrClient());
  }
}

The configuration above sets up an EmbeddedSolrServer which is used by the SolrTemplate . Spring Data Solr Repositories are activated using the @EnableSolrRepositories 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.

5.1.3. Solr Repositores using CDI

The Spring Data Solr repositories can also be set up using CDI functionality.

Example 46. Spring Data Solr repositories using JavaConfig
class SolrTemplateProducer {

  @Produces
  @ApplicationScoped
  public SolrOperations createSolrTemplate() {
    return new SolrTemplate(new EmbeddedSolrServerFactory("classpath:com/acme/solr"));
  }
}

class ProductService {

  private ProductRepository repository;

  public Page<Product> findAvailableProductsByName(String name, Pageable pageable) {
    return repository.findByAvailableTrueAndNameStartingWith(name, pageable);
  }

  @Inject
  public void setRepository(ProductRepository repository) {
    this.repository = repository;
  }
}

5.1.4. Transaction Support

Solr supports transactions on server level means create, updaet, delete actions since the last commit/optimize/rollback are queued on the server and committed/optimized/rolled back at once. Spring Data Solr Repositories will participate in Spring Managed Transactions and commit/rollback changes on complete.

@Transactional
public Product save(Product product) {
  Product savedProduct = jpaRepository.save(product);
  solrRepository.save(savedProduct);
  return savedProduct;
}

5.2. Query methods

5.2.1. Query lookup strategies

The Solr module supports defining a query manually as String or have it being derived from the method name. NOTE: There is no QueryDSL Support present at this time.

Declared queries

Deriving the query from the method name is not always sufficient and/or may result in unreadable method names. In this case one might make either use of Solr named queries (see Using NamedQueries ) or use the @Query annotation (see Using @Query Annotation ).

5.2.2. Query creation

Generally the query creation mechanism for Solr works as described in Query methods . Here’s a short example of what a Solr query method translates into:

Example 47. Query creation from method names
public interface ProductRepository extends Repository<Product, String> {
  List<Product> findByNameAndPopularity(String name, Integer popularity);
}

The method name above will be translated into the following solr query

q=name:?0 AND popularity:?1

A list of supported keywords for Solr is shown below.

Table 2. Supported keywords inside method names
Keyword Sample Solr Query String

And

findByNameAndPopularity

q=name:?0 AND popularity:?1

Or

findByNameOrPopularity

q=name:?0 OR popularity:?1

Is

findByName

q=name:?0

Not

findByNameNot

q=-name:?0

IsNull

findByNameIsNull

q=-name:[* TO *]

IsNotNull

findByNameIsNotNull

q=name:[* TO *]

Between

findByPopularityBetween

q=popularity:[?0 TO ?1]

LessThan

findByPopularityLessThan

q=popularity:[* TO ?0}

LessThanEqual

findByPopularityLessThanEqual

q=popularity:[* TO ?0]

GreaterThan

findByPopularityGreaterThan

q=popularity:{?0 TO *]

GreaterThanEqual

findByPopularityGreaterThanEqual

q=popularity:[?0 TO *]

Before

findByLastModifiedBefore

q=last_modified:[* TO ?0}

After

findByLastModifiedAfter

q=last_modified:{?0 TO *]

Like

findByNameLike

q=name:?0*

NotLike

findByNameNotLike

q=-name:?0*

StartingWith

findByNameStartingWith

q=name:?0*

EndingWith

findByNameEndingWith

q=name:*?0

Containing

findByNameContaining

q=name:*?0*

Matches

findByNameMatches

q=name:?0

In

findByNameIn(Collection<String> names)

q=name:(?0…​ )

NotIn

findByNameNotIn(Collection<String> names)

q=-name:(?0…​ )

Within

findByStoreWithin(Point, Distance)

q={!geofilt pt=?0.latitude,?0.longitude sfield=store d=?1}

Near

findByStoreNear(Point, Distance)

q={!bbox pt=?0.latitude,?0.longitude sfield=store d=?1}

Near

findByStoreNear(Box)

q=store[?0.start.latitude,?0.start.longitude TO ?0.end.latitude,?0.end.longitude]

True

findByAvailableTrue

q=inStock:true

False

findByAvailableFalse

q=inStock:false

OrderBy

findByAvailableTrueOrderByNameDesc

q=inStock:true&sort=name desc
Collections types can be used along with 'Like', 'NotLike', 'StartingWith', 'EndingWith' and 'Containing'. 
Page<Product> findByNameLike(Collection<String> name);

5.2.3. Using @Query Annotation

Using named queries ( Using NamedQueries ) 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 Solr @Query annotation.

Example 48. Declare query at the method using the @Query annotation.
public interface ProductRepository extends SolrRepository<Product, String> {
  @Query("inStock:?0")
  List<Product> findByAvailable(Boolean available);
}

5.2.4. Using NamedQueries

Named queries can be kept in a properties file and wired to the accroding method. Please mind the naming convention described in Query lookup strategies or use @Query .

Example 49. Declare named query in properties file
Product.findByNamedQuery=popularity:?0
Product.findByName=name:?0
public interface ProductRepository extends SolrCrudRepository<Product, String> {

  List<Product> findByNamedQuery(Integer popularity);

  @Query(name = "Product.findByName")
  List<Product> findByAnnotatedNamedQuery(String name);

}

5.3. Document Mapping

Though there is already support for Entity Mapping within SolrJ, Spring Data Solr ships with its own mapping mechanism shown in the following section. NOTE: DocumentObjectBinder has superior performance. Therefore usage is recommended if there is not need for custom type mapping. You can switch to DocumentObjectBinder by registering SolrJConverter within SolrTemplate.

5.3.1. Mapping Solr Converter

MappingSolrConverter allows you to register custom converters for your SolrDocument and SolrInputDocument as well as for other types nested within your beans. The Converter is not 100% compartible with DocumentObjectBinder and @Indexed has to be added with readonly=true to ignore fields from beeing written to solr.

Example 50. Sample Document Mapping
public class Product {
  @Field
  private String simpleProperty;

  @Field("somePropertyName")
  private String namedPropery;

  @Field
  private List<String> listOfValues;

  @Indexed(readonly = true)
  @Field("property_*")
  private List<String> ignoredFromWriting;

  @Field("mappedField_*")
  private Map<String, List<String>> mappedFieldValues;

  @Dynamic
  @Field("dynamicMappedField_*")
  private Map<String, String> dynamicMappedFieldValues;

  @Field
  private GeoLocation location;

}

Taking a look as the above MappingSolrConverter will do as follows:

Property Write Mapping

simpleProperty

<field name="simpleProperty">value</field>

namedPropery

<field name="somePropertyName">value</field>

listOfValues

<field name="listOfValues">value 1</field> <field name="listOfValues">value 2</field> <field name="listOfValues">value 3</field>

ignoredFromWriting

//not written to document

mappedFieldValues

<field name="mapentry[0].key">mapentry[0].value[0]</field> <field name="mapentry[0].key">mapentry[0].value[1]</field> <field name="mapentry[1].key">mapentry[1].value[0]</field>

dynamicMappedFieldValues

<field name="'dynamicMappedField_' + mapentry[0].key">mapentry[0].value[0]</field> <field name="'dynamicMappedField_' + mapentry[0].key">mapentry[0].value[1]</field> <field name="'dynamicMappedField_' + mapentry[1].key">mapentry[1].value[0]</field>

location

<field name="location">48.362893,14.534437</field>

To register a custom converter one must add CustomConversions to SolrTemplate initializing it with own Converter implementation.

<bean id="solrConverter" class="org.springframework.data.solr.core.convert.MappingSolrConverter">
	<constructor-arg>
		<bean class="org.springframework.data.solr.core.mapping.SimpleSolrMappingContext" />
	</constructor-arg>
	<property name="customConversions" ref="customConversions" />
</bean>

<bean id="customConversions" class="org.springframework.data.solr.core.convert.SolrCustomConversions">
	<constructor-arg>
		<list>
			<bean class="com.acme.MyBeanToSolrInputDocumentConverter" />
		</list>
	</constructor-arg>
</bean>

<bean id="solrTemplate" class="org.springframework.data.solr.core.SolrTemplate">
	<constructor-arg ref="solrClient" />
	<property name="solrConverter" ref="solrConverter" />
</bean>

6. Miscellaneous Solr Operation Support

This chapter covers additional support for Solr operations (such as faceting) that cannot be directly accessed via the repository interface. It is recommended to add those operations as custom implementation as described in Custom implementations for Spring Data repositories .

6.1. Partial Updates

PartialUpdates can be done using PartialUpdate which implements Update.

PartialUpdate update = new PartialUpdate("id", "123");
update.add("name", "updated-name");
solrTemplate.saveBean(update);

6.2. Projection

Projections can be applied via @Query using the fields value.

@Query(fields = { "name", "id" })
List<ProductBean> findByNameStartingWith(String name);

6.3. Faceting

Faceting cannot be directly applied using the SolrRepository but the SolrTemplate holds support for this feature.

FacetQuery query = new SimpleFacetQuery(new Criteria(Criteria.WILDCARD).expression(Criteria.WILDCARD))
  .setFacetOptions(new FacetOptions().addFacetOnField("name").setFacetLimit(5));
FacetPage<Product> page = solrTemplate.queryForFacetPage(query, Product.class);

Facets on fields and/or queries can also be defined using @Facet . Please mind that the result will be a FacetPage . NOTE: Using @Facet allows you to define place holders which will use your input parameter as value.

@Query(value = "*:*")
@Facet(fields = { "name" }, limit = 5)
FacetPage<Product> findAllFacetOnName(Pageable page);
@Query(value = "popularity:?0")
@Facet(fields = { "name" }, limit = 5, prefix="?1")
FacetPage<Product> findByPopularityFacetOnName(int popularity, String prefix, Pageable page);

Solr allows definition of facet parameters on a per field basis. In order to add special facet options to defined fields use FieldWithFacetParameters.

// produces: f.name.facet.prefix=spring
FacetOptions options = new FacetOptions();
options.addFacetOnField(new FieldWithFacetParameters("name").setPrefix("spring"));

6.3.1. Range Faceting

Range faceting queries may be done by configure required ranges on FacetOptions. A simple way to request ranges would be by creating a FacetOption, setting this options to a FacetQuery and query for a facet page through SolrTemplate as follows.

FacetOptions facetOptions = new FacetOptions()
  .addFacetByRange(
     new FieldWithNumericRangeParameters("price", 5, 20, 5)
       .setHardEnd(true)
       .setInclude(FacetRangeInclude.ALL)
  )
  .addFacetByRange(
    new FieldWithDateRangeParameters("release", new Date(1420070400), new Date(946684800), "+1YEAR")
      .setInclude(FacetRangeInclude.ALL)
      .setOther(FacetRangeOther.BEFORE)
  );
facetOptions.setFacetMinCount(0);

Criteria criteria = new SimpleStringCriteria("*:*");
SimpleFacetQuery facetQuery = new SimpleFacetQuery(criteria).setFacetOptions(facetOptions);
FacetPage<ExampleSolrBean> statResultPage = solrTemplate.queryForFacetPage(facetQuery, ExampleSolrBean.class);

There are two implementations of fields for facet range requests:

  • Numeric Facet Range - used to perform range faceting over numeric fields. To request such range faceting an instance of the class org.springframework.data.solr.core.query.FacetOptions.FieldWithNumericRangeParameters can be used. Its instantiation requires a field name, a start value (number), end value (number) and gap (number);

  • Date Facet Range - used to perform range faceting over date fields. To request such range faceting an instance of the class org.springframework.data.solr.core.query.FacetOptions.FieldWithDateRangeParameters can be used. Its instantiation requires a field name, a start value (date), end value (date) and gap (string). The gap for this kind of field can be defined using org.apache.solr.util.DateMathParser (i.e. +6MONTHS+3DAYS/DAY, that would mean 6 months and 3 days in the future from now, rounded down to nearest day).

Additionally the following properties can be configured for a field with range parameters (org.springframework.data.solr.core.query.FacetOptions.FieldWithRangeParameters):

  • Hard End - setHardEnd(Boolean), defines if the last range should be abruptly ended even if the end doesn’t satisfies: (start - end) % gap = 0;

  • Include - setInclude(org.apache.solr.common.params.FacetParams.FacetRangeInclude), defines how boundaries (lower and upper) shall be handled (exclusive or inclusive) on range facet requests;

  • Other - setOther(org.apache.solr.common.params.FacetParams.FacetRangeOther), defines the additional (other) counts for the range facet, i.e. count of documents that are before start of the range facet, end of range facet or even between start and end.

6.3.2. Pivot Faceting

Pivot faceting (Decision Tree) are also supported, and can be queried using @Facet annotation as follows:

public interface {

	@Facet(pivots = @Pivot({ "category", "dimension" }, pivotMinCount = 0))
	FacetPage<Product> findByTitle(String title, Pageable page);

	@Facet(pivots = @Pivot({ "category", "dimension" }))
	FacetPage<Product> findByDescription(String description, Pageable page);

}

Alternatively it can be queried using SolrTemplate as follows:

FacetQuery facetQuery = new SimpleFacetQuery(new SimpleStringCriteria("title:foo"));
FacetOptions facetOptions = new FacetOptions();
facetOptions.setFacetMinCount(0);
facetOptions.addFacetOnPivot("category","dimension");
facetQuery.setFacetOptions(facetOptions);
FacetPage<Product> facetResult = solrTemplate.queryForFacetPage(facetQuery, Product.class);

In order to retrieve the pivot results the method getPivot can be used as follows:

List<FacetPivotFieldEntry> pivot = facetResult.getPivot(new SimplePivotField("categories","available"));

6.4. Terms

Terms Vector cannot directly be used within SolrRepository but can be applied via SolrTemplate. Please mind, that the result will be a TermsPage.

TermsQuery query = SimpleTermsQuery.queryBuilder().fields("name").build();
TermsPage page = solrTemplate.queryForTermsPage(query);

6.5. Result Grouping / Field Collapsing

Result grouping cannot directly be used within SolrRepository but can be applied via SolrTemplate. Please mind, that the result will be a GroupPage.

Field field = new SimpleField("popularity");
Function func = ExistsFunction.exists("description");
Query query = new SimpleQuery("inStock:true");

SimpleQuery groupQuery = new SimpleQuery(new SimpleStringCriteria("*:*"));
GroupOptions groupOptions = new GroupOptions()
	.addGroupByField(field)
	.addGroupByFunction(func)
	.addGroupByQuery(query);
groupQuery.setGroupOptions(groupOptions);

GroupPage<Product> page = solrTemplate.queryForGroupPage(query, Product.class);

GroupResult<Product> fieldGroup = page.getGroupResult(field);
GroupResult<Product> funcGroup = page.getGroupResult(func);
GroupResult<Product> queryGroup = page.getGroupResult(query);

6.6. Field Stats

Field stats are used to retrieve statistics (max, min, sum, count, mean, missing, stddev and distinct calculations) of given fields from Solr. It is possible by providing StatsOptions to your query and reading the FieldStatsResult from the returned StatsPage. This could be achieved for instance, using SolrTemplate as follows:

// simple field stats
StatsOptions statsOptions = new StatsOptions().addField("price");

// query
SimpleQuery statsQuery = new SimpleQuery("*:*");
statsQuery.setStatsOptions(statsOptions);
StatsPage<Product> statsPage = solrTemplate.queryForStatsPage(statsQuery, Product.class);

// retrieving stats info
FieldStatsResult priceStatResult = statResultPage.getFieldStatsResult("price");
Object max = priceStatResult.getMax();
Long missing = priceStatResult.getMissing();

The same result could be achieved annotating the repository method with @Stats as follows:

@Query("name:?0")
@Stats(value = { "price" })
StatsPage<Product> findByName(String name, Pageable page);

Distinct calculation and faceting are also supported:

// for distinct calculation
StatsOptions statsOptions = new StatsOptions()
    .addField("category")
    // for distinct calculation
    .setCalcDistinct(true)
    // for faceting
    .addFacet("availability");

// query
SimpleQuery statsQuery = new SimpleQuery("*:*");
statsQuery.setStatsOptions(statsOptions);
StatsPage<Product> statsPage = solrTemplate.queryForStatsPage(statsQuery, Product.class);

// field stats
FieldStatsResult categoryStatResult = statResultPage.getFieldStatsResult("category");

// retrieving distinct
List<Object> categoryValues = priceStatResult.getDistinctValues();
Long distinctCount = categoryStatResult.getDistinctCount();

// retrieving faceting
Map<String, StatsResult> availabilityFacetResult = categoryStatResult.getFacetStatsResult("availability");
Long availableCount = availabilityFacetResult.get("true").getCount();

The annotated version of the sample above would be:

@Query("name:?0")
@Stats(value = "category", facets = { "availability" }, calcDistinct = true)
StatsPage<Product> findByName(String name);

In order to perform a selective faceting or selective distinct calculation, @SelectiveStats may be used as follows:

// selective distinct faceting
...
Field facetField = getFacetField();
StatsOptions statsOptions = new StatsOptions()
    .addField("price")
    .addField("category").addSelectiveFacet("name").addSelectiveFacet(facetField);
...
// or annotating repository method as follows
...
@Stats(value = "price", selective = @SelectiveStats(field = "category", facets = { "name", "available" }))
...

// selective distinct calculation
...
StatsOptions statsOptions = new StatsOptions()
    .addField("price")
    .addField("category").setSelectiveCalcDistinct(true);
...
// or annotating repository method as follows
...
@Stats(value = "price", selective = @SelectiveStats(field = "category", calcDistinct = true))
...

6.7. Filter Query

Filter Queries improve query speed and do not influence document score. It is recommended to implement geospatial search as filter query. NOTE: Please note that in solr, unless otherwise specified, all units of distance are kilometers and points are in degrees of latitude,longitude.

Query query = new SimpleQuery(new Criteria("category").is("supercalifragilisticexpialidocious"));
FilterQuery fq = new SimpleFilterQuery(new Criteria("store")
  .near(new Point(48.305478, 14.286699), new Distance(5)));
query.addFilterQuery(fq);

Simple filter queries can also be defined using @Query . NOTE: Using @Query allows you to define place holders which will use your input parameter as value.

@Query(value = "*:*", filters = { "inStock:true", "popularity:[* TO 3]" })
List<Product> findAllFilterAvailableTrueAndPopularityLessThanEqual3();

6.8. Time allowed for a search

It it possible to set the time allowed for a search to finish. This value only applies to the search and not to requests in general. Time is in milliseconds. Values less than or equal to zero implies no time restriction. Partial results may be returned, if there are any.

Query query = new SimpleQuery(new SimpleStringCriteria("field_1:value_1"));
// Allowing maximum of 100ms for this search
query.setTimeAllowed(100);

6.9. Boost document Score

Boost document score in case of matching criteria to influence result order. This can be done by either setting boost on Criteria or using @Boost for derived queries.

Page<Product> findByNameOrDescription(@Boost(2) String name, String description);

6.9.1. Index Time Boosts

Boosting documents score can be done on index time by using @SolrDocument annotation on classes (for Solr documents) and/or @Indexed on fields (for Solr fields).

import org.apache.solr.client.solrj.beans.Field;
import org.springframework.data.solr.repository.Boost;

@SolrDocument(boost = 0.8f)
public class MyEntity {

    @Id
    @Indexed
    private String id;

    @Indexed(boost = 1.0f)
    private String name;

    // setters and getters ...

}

6.10. Select Request Handler

Select the request handler via qt Parameter directly in Query or add @Query to your method signature.

@Query(requestHandler = "/instock")
Page<Product> findByNameOrDescription(String name, String description);

6.11. Using Join

Join attributes within one solr core by defining Join attribute of Query. NOTE: Join is not available prior to solr 4.x.

SimpleQuery query = new SimpleQuery(new SimpleStringCriteria("text:ipod"));
query.setJoin(Join.from("manu_id_s").to("id"));

6.12. Highlighting

To highlight matches in search result add HighlightOptions to the SimpleHighlightQuery. Providing HighlightOptions without any further attributes will highlight apply highlighting on all fields within a SolrDocument. NOTE: Field specific highlight parameters can be set by adding FieldWithHighlightParameters to HighlightOptions.

SimpleHighlightQuery query = new SimpleHighlightQuery(new SimpleStringCriteria("name:with"));
query.setHighlightOptions(new HighlightOptions());
HighlightPage<Product> page = solrTemplate.queryForHighlightPage(query, Product.class);

Not all parameters are available via setters/getters but can be added directly.

SimpleHighlightQuery query = new SimpleHighlightQuery(new SimpleStringCriteria("name:with"));
query.setHighlightOptions(new HighlightOptions().addHighlightParameter("hl.bs.country", "at"));

In order to apply Highlighting to derived queries use @Highlight. If no fields are defined highlighting will be aplied on all fields.

@Highlight(prefix = "<b>", postfix = "</b>")
HighlightPage<Product> findByName(String name, Pageable page);

6.13. Spellchecking

Spellchecking offers search term suggestions based on the actual query. Please see the Solr Reference for more details.

6.13.1. Spellecheck Options

Spellcheck query parameters are added to request when SpellcheckOptions are set.

SimpleQuery q = new SimpleQuery("name:gren");
q.setSpellcheckOptions(SpellcheckOptions.spellcheck()               (1)
  .dictionaries("dict1", "dict2")                                   (2)
  .count(5)                                                         (3)
  .extendedResults());                                              (4)
q.setRequestHandler("/spell");                                      (5)

SpellcheckedPage<Product> found = template.query(q, Product.class); (6)
1 Enable spellcheck by setting SpellcheckOptions. Sets spellcheck=on request parameter.
2 Set up the dictionaries to use for lookup.
3 Set the max number of suggestions to return.
4 Enable extended results including term frequency etc.
5 Set the request handler capable of processing suggestions.
6 Execute the query.

6.13.2. @Spellcheck

The @Spellcheck annotations allows usage of the spellcheck feature on Repository level.

public interface ProductRepository extends Repository<Product, String> {

  @Query(requestHandler = "/spell")
  @Spellcheck(dictionaries = { "dict1", "dic2" }, count=5, extendedResults = true)
  SpellcheckedPage<Product> findByName(String name, Pageable page);

}

6.14. Using Functions

Solr supports several functional expressions within queries. Followig functions are supported out of the box. Custom functions can be added by implementing Function

Table 3. Functions
Class Solr Function

CurrencyFunction

currency(field_name,[CODE])

DefaultValueFunction

def(field|function,defaultValue)

DistanceFunction

dist(power, pointA, pointB)

DivideFunction

div(x,y)

ExistsFunction

exists(field|function)

GeoDistanceFunction

geodist(sfield, latitude, longitude)

GeoHashFunction

geohash(latitude, longitude)

IfFunction

if(value|field|function,trueValue,falseValue)

MaxFunction

max(field|function,value)

NotFunction

not(field|function)

ProductFunction

product(x,y,…​)

QueryFunction

query(x)

TermFrequencyFunction

termfreq(field,term)

 
SimpleQuery query = new SimpleQuery(new SimpleStringCriteria("text:ipod"));
query.addFilterQuery(new FilterQuery(Criteria.where(QueryFunction.query("name:sol*"))));

6.15. Realtime Get

The realtime get allows retrieval of the latest version of any document using the unique-key, without the need to reopen searchers.

realtime get relies on the update log feature.
Example 51. Realtime get
Product product = solrTemplate.getById("123", Product.class);

Multiple documents can be retrieved by providing a collection of ids as follows:

Example 52. Realtime multi-get
Collection<String> ids = Arrays.asList("123", "134");
Collection<Product> products = solrTemplate.getById(ids, Product.class);

6.16. Special Fields

6.16.1. @Score

In order to load score information of a query result, a field annotated with @Score annotation could be added, indicating the property holding the documents score.

The score property needs to be numerical and can only appear once per document. 
public class MyEntity {

    @Id
    private String id;

    @Score
    private Float score;

    // setters and getters ...

}

Appendix

Appendix A: Namespace reference

The <repositories /> element

The <repositories /> element triggers the setup of the Spring Data repository infrastructure. The most important attribute is base-package which defines the package to scan for Spring Data repository interfaces.[3]

Table 4. Attributes
Name Description

base-package

Defines 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. Wildcards are allowed.

repository-impl-postfix

Defines 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-strategy

Determines the strategy to be used to create finder queries. See Query lookup strategies for details. Defaults to create-if-not-found.

named-queries-location

Defines the location to look for a Properties file containing externally defined queries.

consider-nested-repositories

Controls whether nested repository interface definitions should be considered. Defaults to false.

Appendix B: Populators namespace reference

The <populator /> element

The <populator /> element allows to populate the a data store via the Spring Data repository infrastructure.[4]

Table 5. Attributes
Name Description

locations

Where to find the files to read the objects from the repository shall be populated with.

Appendix C: Repository query keywords

Supported query keywords

The following table lists the keywords generally supported by the Spring Data repository query derivation mechanism. However, consult the store-specific documentation for the exact list of supported keywords, because some listed here might not be supported in a particular store.

Table 6. Query keywords
Logical keyword Keyword expressions

AND

And

OR

Or

AFTER

After, IsAfter

BEFORE

Before, IsBefore

CONTAINING

Containing, IsContaining, Contains

BETWEEN

Between, IsBetween

ENDING_WITH

EndingWith, IsEndingWith, EndsWith

EXISTS

Exists

FALSE

False, IsFalse

GREATER_THAN

GreaterThan, IsGreaterThan

GREATER_THAN_EQUALS

GreaterThanEqual, IsGreaterThanEqual

IN

In, IsIn

IS

Is, Equals, (or no keyword)

IS_EMPTY

IsEmpty, Empty

IS_NOT_EMPTY

IsNotEmpty, NotEmpty

IS_NOT_NULL

NotNull, IsNotNull

IS_NULL

Null, IsNull

LESS_THAN

LessThan, IsLessThan

LESS_THAN_EQUAL

LessThanEqual, IsLessThanEqual

LIKE

Like, IsLike

NEAR

Near, IsNear

NOT

Not, IsNot

NOT_IN

NotIn, IsNotIn

NOT_LIKE

NotLike, IsNotLike

REGEX

Regex, MatchesRegex, Matches

STARTING_WITH

StartingWith, IsStartingWith, StartsWith

TRUE

True, IsTrue

WITHIN

Within, IsWithin

Appendix D: Repository query return types

Supported query return types

The following table lists the return types generally supported by Spring Data repositories. However, consult the store-specific documentation for the exact list of supported return types, because some listed here might not be supported in a particular store.

Geospatial types like (GeoResult, GeoResults, GeoPage) are only available for data stores that support geospatial queries.
Table 7. Query return types
Return type Description

void

Denotes no return value.

Primitives

Java primitives.

Wrapper types

Java wrapper types.

T

An unique entity. Expects the query method to return one result at most. In case no result is found null is returned. More than one result will trigger an IncorrectResultSizeDataAccessException.

Iterator<T>

An Iterator.

Collection<T>

A Collection.

List<T>

A List.

Optional<T>

A Java 8 or Guava Optional. Expects the query method to return one result at most. In case no result is found Optional.empty()/Optional.absent() is returned. More than one result will trigger an IncorrectResultSizeDataAccessException.

Option<T>

An either Scala or JavaSlang Option type. Semantically same behavior as Java 8’s Optional described above.

Stream<T>

A Java 8 Stream.

Future<T>

A Future. Expects method to be annotated with @Async and requires Spring’s asynchronous method execution capability enabled.

CompletableFuture<T>

A Java 8 CompletableFuture. Expects method to be annotated with @Async and requires Spring’s asynchronous method execution capability enabled.

ListenableFuture

A org.springframework.util.concurrent.ListenableFuture. Expects method to be annotated with @Async and requires Spring’s asynchronous method execution capability enabled.

Slice

A sized chunk of data with information whether there is more data available. Requires a Pageable method parameter.

Page<T>

A Slice with additional information, e.g. the total number of results. Requires a Pageable method parameter.

GeoResult<T>

A result entry with additional information, e.g. distance to a reference location.

GeoResults<T>

A list of GeoResult<T> with additional information, e.g. average distance to a reference location.

GeoPage<T>

A Page with GeoResult<T>, e.g. average distance to a reference location.
1. JavaConfig in the Spring reference documentation
2. Spring HATEOAS - https://github.com/SpringSource/spring-hateoas
3. see XML configuration
4. see XML configuration