springboot3整合高版本spring data neo4j

本博客适用于springboo data neo4j 7.2.6版本，详情阅读官网https://docs.spring.io/spring-data/neo4j/reference/7.2/introduction-and-preface/index.html，中文网只更新到了6版本

entity->node entity->relation

@Node("Movie")  // 取代了老版本的nodeentity，他表示的就是label
public class MovieEntity {

    @Id  // id标识没什么好说的，官方也提供了自动生成@GeneratedValue
    private final String title;

    @Property("tagline") // 代表一个label的属性
    private final String description;

    @Relationship(type = "ACTED_IN", direction = Direction.INCOMING) // 关系的创建直接在entity里即可，本样例中就是(MovieEntity)-[ACTED_IN]->(Roles)。向后阅读，这里是一个复合关系吗，用到了@RelationshipProperties
    private List<Roles> actorsAndRoles;

    @Relationship(type = "DIRECTED", direction = Direction.INCOMING) // 本样例是(MovieEntity)-[DIRECTED]->(PersonEntity)
    private List<PersonEntity> directors = new ArrayList<>();

    public MovieEntity(String title, String description) {  // 需要构造函数
        this.title = title;
        this.description = description;
    }

    // Getters omitted for brevity
}

一些映射注解

    @Node：表示类对数据库的映射
    @Id：
    @GeneratedValue：与 @Id一起应用，以指定应如何生成唯一标识符
    @Property：类属性对node属性的映射
    @Relationship：类属性对relation的映射，这个用在类内，指明(node)-[relation]->(node)
    @RelationshipProperties：类对relation的映射，这个用在类外，指明relation具体有什么属性　　
    @TargetNode：用于 @RelationshipProperties注解的类的字段，以从另一端的角度标记该关系的目标

@Relationship：type/value为允许配置关系的类型，direction指定了方向，默认为OUTGOING

@RelationshipProperties使用案例：

@RelationshipProperties
public class Roles {

    @RelationshipId
    private Long id;

    private final List<String> roles;

    @TargetNode
    private final PersonEntity person;

    public Roles(PersonEntity person, List<String> roles) {
        this.person = person;
        this.roles = roles;
    }

    public List<String> getRoles() {
        return roles;
    }
}

示例（可选使用）基于neo4jclient的生成器

@Component
class MyIdGenerator implements IdGenerator<String> {
    private final Neo4jClient neo4jClient;
    public MyIdGenerator(Neo4jClient neo4jClient) {
        this.neo4jClient = neo4jClient;
    }
    @Override
    public String generateId(String primaryLabel, Object entity) {
        return neo4jClient.query("YOUR CYPHER QUERY FOR THE NEXT ID") //(1)
            .fetchAs(String.class).one().get();
    }
}

@Node("Movie")
public class MovieEntity {
    @Id @GeneratedValue(generatorRef = "myIdGenerator")
    private String id;
    private String name;
}

如何创建一个dao

@Repository
public interface IndustryDao extends Neo4jRepository<Industry,Long> {
}