Skill v1.0.1
currentAutomated scan100/100+3 new
name: neo4j-spring-data-skill description: Use when building Spring Boot applications with Neo4j using Spring Data Neo4j (SDN 7.x/8.x): @Node entity mapping, @Relationship, @RelationshipProperties, Neo4jRepository, ReactiveNeo4jRepository, @Query annotations, application.yml configuration, projections, Neo4jClient, Neo4jTemplate, transactions, auditing, or Spring AI Neo4jVectorStore vector search. Does NOT handle raw Java driver code without Spring — use neo4j-driver-java-skill. Does NOT handle Cypher query authoring — use neo4j-cypher-skill. Does NOT handle driver version upgrades — use neo4j-migration-skill. version: 1.0.1 allowed-tools: Bash WebFetch
Neo4j Spring Data Skill
When to Use
- Configuring Spring Boot with Neo4j (
spring-boot-starter-data-neo4j) - Writing
@Nodeentity classes and@Relationship/@RelationshipPropertiesmappings - Defining
Neo4jRepositoryorReactiveNeo4jRepositoryinterfaces - Writing
@Queryannotations with Cypher on repository methods - Using Spring projections (interface-based, DTO, dynamic) with Neo4j
- Configuring
application.ymlfor Neo4j connection - Custom queries via
Neo4jClientorNeo4jTemplate - Spring AI
Neo4jVectorStorefor vector search in Spring apps - Transaction management, auditing, optimistic locking
When NOT to Use
- Raw Java driver without Spring →
neo4j-driver-java-skill - Cypher query authoring →
neo4j-cypher-skill - Driver version upgrades →
neo4j-migration-skill - GDS algorithms →
neo4j-gds-skill
Version Matrix
| SDN | Spring Boot | Spring Framework | Java | Neo4j | |
|---|---|---|---|---|---|
| 8.0.x | 3.3.x / 3.4.x | 6.2.x | 17+ | 5.15+ | |
| 8.1.x | 3.4.x+ | 7.0.x | 17+ | 5.15+ | |
| 7.5.x | 3.2.x | 6.1.x | 17+ | 4.4+ |
Use spring-boot-starter-data-neo4j — it pulls SDN + driver. No explicit SDN version needed when using Spring Boot BOM.
Setup
Maven
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-data-neo4j</artifactId></dependency>
Gradle
implementation 'org.springframework.boot:spring-boot-starter-data-neo4j'
Reactive stack (add alongside above)
<dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-webflux</artifactId></dependency>
Configuration
application.yml — imperative (standard)
spring:neo4j:uri: ${NEO4J_URI:bolt://localhost:7687}authentication:username: ${NEO4J_USERNAME:neo4j}password: ${NEO4J_PASSWORD}data:neo4j:database: ${NEO4J_DATABASE:neo4j}
application.yml — Aura (TLS required)
spring:neo4j:uri: ${NEO4J_URI} # neo4j+s://xxxx.databases.neo4j.ioauthentication:username: ${NEO4J_USERNAME:neo4j}password: ${NEO4J_PASSWORD}data:neo4j:database: ${NEO4J_DATABASE:neo4j}
Credentials: store in .env; never hardcode. Verify .env is in .gitignore.
Entity Mapping
import org.springframework.data.neo4j.core.schema.*;// Internal generated ID (default for most cases)@Node("Person")public class PersonEntity {@Id @GeneratedValue private Long id; // element ID (Long)private String name;@Property("birth_year") private Integer birthYear; // custom property name@Relationship(type = "KNOWS", direction = Relationship.Direction.OUTGOING)private List<PersonEntity> friends = new ArrayList<>();}// UUID business key@Node("Product")public class ProductEntity {@Id @GeneratedValue(generatorClass = GeneratedValue.UUIDStringGenerator.class)private String id;@Version private Long version; // optimistic locking; required with business key}// User-assigned key (caller sets value; no @GeneratedValue)@Node("Country")public class CountryEntity {@Id private String isoCode;private String name;}// Multiple static labels@Node(primaryLabel = "Vehicle", labels = {"Car", "Auditable"})public class CarEntity { ... }// Runtime labels@Node("Content")public class ContentEntity {@Id @GeneratedValue private Long id;@DynamicLabels private Set<String> tags = new HashSet<>(); // labels added at runtime}
Relationship Properties
Use @RelationshipProperties when the relationship itself carries data.
@RelationshipPropertiespublic class RolesRelationship {@RelationshipId // internal relationship ID; requiredprivate Long id;private List<String> roles;@TargetNode // marks the other end of the relationshipprivate PersonEntity person;}
@Node("Movie")public class MovieEntity {@Id @GeneratedValueprivate Long id;private String title;@Relationship(type = "ACTED_IN", direction = Relationship.Direction.INCOMING)private List<RolesRelationship> actorsAndRoles = new ArrayList<>();}
Repository Interfaces
Basic CRUD
import org.springframework.data.neo4j.repository.Neo4jRepository;public interface PersonRepository extends Neo4jRepository<PersonEntity, Long> {Optional<PersonEntity> findByName(String name);List<PersonEntity> findByBirthYearBetween(int from, int to);List<PersonEntity> findByNameContainingIgnoreCase(String fragment);long countByBirthYearGreaterThan(int year);void deleteByName(String name);}
@Query — custom Cypher
// CORRECT: $param bound parameter@Query("MATCH (p:Person {name: $name})-[:KNOWS]->(f:Person) RETURN f")List<PersonEntity> findFriendsOf(String name);// With pagination@Query(value = "MATCH (p:Person) RETURN p ORDER BY p.name",countQuery = "MATCH (p:Person) RETURN count(p)")Page<PersonEntity> findAllPaged(Pageable pageable);// Return relationship-rich entity; map target via @Node return@Query("MATCH (m:Movie)<-[r:ACTED_IN]-(p:Person {name: $name}) RETURN m, collect(r), collect(p)")List<MovieEntity> findMoviesActedInBy(String name);
Security rule: NEVER string-concatenate user input into Cypher. Always use $paramName.
Pagination and sorting
Page<PersonEntity> findByBirthYearGreaterThan(int year, Pageable pageable);List<PersonEntity> findTop10ByOrderByNameAsc();List<PersonEntity> findByName(String name, Sort sort);
Usage:
Pageable page = PageRequest.of(0, 20, Sort.by("name").ascending());Page<PersonEntity> result = repo.findByBirthYearGreaterThan(1980, page);
Projections
Interface projection (closed — query-optimizable)
public interface PersonSummary {String getName();Integer getBirthYear();}List<PersonSummary> findByBirthYearLessThan(int year);
DTO projection (record — preferred in Java 17+)
public record PersonDto(String name, Integer birthYear) {}List<PersonDto> findByName(String name);
Dynamic projection
<T> List<T> findByName(String name, Class<T> type);// Usagerepo.findByName("Alice", PersonSummary.class);repo.findByName("Alice", PersonEntity.class);
Open projection — SpEL (disables query optimization)
public interface FullName {@Value("#{target.name + ' (' + target.birthYear + ')'}") String getDisplayName();}
Reactive Repository
import org.springframework.data.neo4j.repository.ReactiveNeo4jRepository;import reactor.core.publisher.Flux;import reactor.core.publisher.Mono;public interface ReactivePersonRepository extends ReactiveNeo4jRepository<PersonEntity, Long> {Mono<PersonEntity> findByName(String name);@Query("MATCH (p:Person {name: $name})-[:KNOWS]->(f) RETURN f")Flux<PersonEntity> findFriendsOf(String name);}
Do NOT mix imperative and reactive database access in the same application context.
Custom Repository Implementation
Fragment pattern — use when @Query is not enough.
// 1. Fragment interfacepublic interface PersonRepositoryCustom {List<PersonEntity> findByComplexCriteria(String criteria);}// 2. Impl — must end with "Impl"public class PersonRepositoryCustomImpl implements PersonRepositoryCustom {private final Neo4jClient neo4jClient;PersonRepositoryCustomImpl(Neo4jClient c) { this.neo4jClient = c; }@Overridepublic List<PersonEntity> findByComplexCriteria(String c) {return new ArrayList<>(neo4jClient.query("MATCH (p:Person) WHERE p.name CONTAINS $c RETURN p").bind(c).to("c").fetchAs(PersonEntity.class).mappedBy((t, r) -> { var e = new PersonEntity(); e.setName(r.get("p").asNode().get("name").asString()); return e; }).all());}}// 3. Composepublic interface PersonRepository extends Neo4jRepository<PersonEntity, Long>, PersonRepositoryCustom {}
Neo4jClient — Low-Level Queries
Use when @Query is insufficient or you need full control over Cypher execution.
// Bind params + fetch single scalarneo4jClient.query("MATCH (p:Person {name: $name}) RETURN count(*) AS cnt").bind("Alice").to("name").fetchAs(Long.class).mappedBy((t, r) -> r.get("cnt").asLong()).one();// Bind + run write (no result)neo4jClient.query("MERGE (p:Person {name: $name})").bind(personName).to("name").run();// Custom object mappingneo4jClient.query("MATCH (p:Person)-[:DIRECTED]->(m:Movie) WHERE p.name=$n RETURN p, collect(m) AS movies").bind("Lilly Wachowski").to("n").fetchAs(Director.class).mappedBy((typeSystem, record) -> new Director(record.get("p").asNode().get("name").asString(),record.get("movies").asList(v -> new Movie(v.get("title").asString())))).one();
Full API: references/neo4j-client.md
Transaction Management
@Service@Transactional // class-level: all methods transactionalpublic class PersonService {@Transactional(readOnly = true) // read-only hintpublic Optional<PersonEntity> findByName(String name) { ... }@Transactional // explicit writepublic PersonEntity save(PersonEntity p) { return repository.save(p); }}
Neo4jTransactionManager auto-configured. Do NOT mix with JPA PlatformTransactionManager without explicit qualifier. Use @Transactional on concrete class, not interface.
Spring AI — Neo4jVectorStore
Dependency
<dependency><groupId>org.springframework.ai</groupId><artifactId>spring-ai-starter-vector-store-neo4j</artifactId></dependency>
application.yml
spring:ai:vectorstore:neo4j:initialize-schema: true # creates vector index on first runindex-name: my-indexembedding-dimension: 1536 # must match your embedding modeldistance-type: cosine # cosine (default) or euclideanlabel: Document # node label for stored chunksembedding-property: embedding # property for the vector
Requires Neo4j 5.15+. Reuses spring.neo4j.* connection config.
Usage
@Autowired VectorStore vectorStore;// StorevectorStore.add(List.of(new Document("text", Map.of("author", "alice"))));// Similarity searchList<Document> results = vectorStore.similaritySearch(SearchRequest.builder().query("spring neo4j").topK(5).similarityThreshold(0.75).build());// With metadata filtervectorStore.similaritySearch(SearchRequest.builder().query("spring neo4j").topK(5).filterExpression("author == 'alice'").build());
Common Errors
| Error | Cause | Fix | |
|---|---|---|---|
MappingException: Could not find entity | Entity not scanned | Check @EnableNeo4jRepositories base package | |
| Relationships null after load | Default depth may skip deep rels | Use @Query with RETURN m, collect(r), collect(p) | |
| N+1 queries | Per-entity relationship fetch | Rewrite with single @Query; use projections | |
OptimisticLockingFailureException | Stale @Version on concurrent write | Retry in service layer | |
IllegalStateException: Cannot mix reactive/imperative | Both repo types in same context | Pick one stack | |
| Projection null fields | Getter name mismatch | Match getter to property name; check @Property alias | |
@Query empty with rels | Missing collect(r), collect(p) | Return root node + rels + related nodes together | |
Cannot delete node, node has relationships | deleteById without detach | Use @Query with DETACH DELETE | |
| Transaction not rolling back | @Transactional on interface | Apply on concrete service class |
Relationship Loading — Key Rule
SDN loads related entities eagerly up to a configured depth (default: 1 hop). For deeper graphs:
// Explicit @Query to control what gets loaded@Query("""MATCH (m:Movie)<-[r:ACTED_IN]-(p:Person)WHERE m.title = $titleRETURN m, collect(r), collect(p)""")Optional<MovieEntity> findByTitleWithCast(String title);
collect(r), collect(p) in RETURN is required for SDN to map @RelationshipProperties correctly.
References
- Spring Data Neo4j Reference (8.x)
- Spring AI Neo4jVectorStore
- GraphAcademy: Building Neo4j Apps with Spring Data
- Neo4j Getting Started — SDN
- SDN Advanced projections
- SDN Auditing
- Modeling pitfalls, projection guide, type mapping
Checklist
- [ ]
@Nodeuses explicit label string, not default class name - [ ]
@Id @GeneratedValue(or@Id+@Versionfor business key with optimistic lock) - [ ]
@RelationshipPropertiesclass has@RelationshipIdand@TargetNode - [ ]
@Relationshipdirection is explicit (OUTGOING / INCOMING) - [ ]
@QueryCypher uses$paramName— no string concatenation - [ ] Relationship-rich
@Queryreturnscollect(r), collect(p)alongside root node - [ ] Database name set in
application.yml(avoids default DB ambiguity) - [ ] Unique constraint exists in DB for any business key used in repository lookups
- [ ]
@Transactionalon concrete service class (not interface) - [ ] No imperative + reactive mix in same application context
- [ ] Credentials in env vars;
.envin.gitignore - [ ]
spring.ai.vectorstore.neo4j.initialize-schema: truefor first run (Spring AI)