GraphRD Spring Data module

Spring Data repositories for GraphRD — Spring's own repository structure on top of the pure-Java client. All Spring integration lives in this module: the client jar carries no Spring at all, and this module brings both the starter (auto-wiring RdfClient/RdfEntityManager from graphrd.* settings) and the repository structure described below. Java 17+.

Install

One dependency — the client comes with it. The module's version is the Spring Boot version it is built on: pick the one that matches your application (4.1.1 for Spring Boot 4.1.x).

<dependency>
  <groupId>org.graphrd</groupId>
  <artifactId>graphrd-spring-data</artifactId>
  <version>4.1.1</version>
</dependency>

Getting started

Being on the classpath is the whole setup — the application's own packages are scanned, no annotation anywhere (exactly like JPA in a Spring Boot application):

interface People extends GraphRdRepository<Person, String> {
    Optional<Person> findByName(String name);
    List<Person>  findByAgeGreaterThanAndSalaryLessThan(int age, int salary);
    List<Person>  findByWorksFor(String companyIri);      // reference equality, by IRI
    List<Person>  findByNameStartingWithIgnoreCase(String prefix);
    Page<Person>  findByAgeGreaterThan(int age, Pageable pageable);   // items + total
    List<Person>  findBySalaryGreaterThanOrderBySalaryDesc(int salary);
    long          countByWorksFor(String companyIri);
    void          deleteByName(String name);
}

That one interface carries:

• the standard CRUD of CrudRepository/PagingAndSortingRepository — saves in one chained request, lists with references resolved in bulk, findAll(Pageable) pages with the total, findAll(Sort) sorts (multi-key);
• derived queries parsed by Spring Data itself (PartTree), translated to the mapper's criteria: comparisons, Between, In, the Like family, IgnoreCase, IsNull, True/False, OrderBy in the name, First/Top limits, exists…By, count…By, delete…By;
• an equality on a reference field compares IRIs automatically.

An explicit @EnableGraphRdRepositories (with basePackages, considerNestedRepositories and friends) still wins over the automatic scan, and spring.data.graphrd.repositories.enabled=false turns it off entirely.

Dynamic search: specifications

Free-form filter mixes that do not fit one method name are the mapper's specifications — compose and run, no custom repository, ever:

GraphRdSpecification<Person> spec = GraphRdSpecifications.greaterThan(Person::getAge, 30)
        .and(GraphRdSpecifications.ref("worksFor", companyIri))
        .and(GraphRdSpecifications.ilike(Person::getName, "a%"));

Page<Person> page = people.findAll(spec, pageable);   // also findAll(spec), findAll(spec, Sort), count(spec)

Custom queries: @Query

Hand-written SPARQL, :param binding, answers mapped to records:

@Query("PREFIX ex: <http://ex.org/> SELECT ?company (COUNT(?e) AS ?heads)"
     + " WHERE { ?e a ex:Person ; ex:worksFor [ ex:name ?company ] } GROUP BY ?company")
List<Headcount> headcount();   // record Headcount(String company, long heads)

@Query("… FILTER(?a >= :lo && ?a <= :hi) …")
List<String> namesBetween(int lo, int hi);   // parameters bind as literals

Configuration

The starter wires everything from graphrd.* in application.yml — a Spring Boot application writes no configuration code:

Property	Default	Meaning
graphrd.base-url	—	the server, e.g. http://localhost:7200
graphrd.repository	—	the repository id
graphrd.namespace	(empty)	vocabulary namespace; short annotation names resolve against it, {ns} in @Query stands for it
graphrd.connect-timeout	5s	connection setup
graphrd.request-timeout	60s	per request
spring.data.graphrd.repositories.enabled	true	repository scanning on/off

The showcase application uses derived queries, specifications and @Query side by side, with zero configuration annotations.

Requirements and tests

Java 17+, Spring Boot 4.x (Spring Framework 7, Spring Data 2026.x) and a running GraphRD server. mvn test boots a throwaway server and runs the whole tour through a real Spring context: it expects the release binary at ../../target/release/graphrd (clone GraphRD next to this repository and run cargo build --release; override with -Dgraphrd.bin=). Without the binary the tests skip.

License

Apache-2.0