Question

实际上，我试图用RelationshipEntity类保存一个节点，如下所示：

节点类

@NodeEntity  
public class MyEvent  
{  
     @GraphId  
     private Long nodeId;  
     @RelatedToVia(type = "INVITED_TO")  
     @Fetch Set<EventResponse> eventResponse;  
}

RelationshipEntity Class

@RelationshipEntity(type="INVITED_TO")  
public class EventResponse  implements Serializable   
{  
   @GraphId  
   Long nodeId;  

   @StartNode  
   MyEvent event;  

   @EndNode  
   User user;  

  //  .....

}

当我尝试保存MyEvent

org.neo4j.graphdb.NotFoundException: '__type__' property not found for RelationshipImpl #153 of type 15 between Node[159] and Node[117].

所以我猜基于上面的异常，它缺少识别任何节点类型所需的__type__属性。我没有完全得到，有没有什么方法可以保存第一个关系实体，然后是NodeEntity或反之亦然？或者

Answer 1

您不需要明确设置类型属性。它由spring-data-neo4j管理。

以下代码段对我有用：

事件类：

@NodeEntity
public class MyEvent
    {

    @GraphId
    private Long       nodeId;

    @RelatedToVia(type = "INVITED_TO")
    @Fetch
    Set<EventResponse> eventResponse;

    }

用户类：

@NodeEntity
public class User
    {

    @GraphId
    private Long userId;  

    }

响应类：

@RelationshipEntity(type = "INVITED_TO")
public class EventResponse
    {

    @GraphId
    private Long    nodeId;

    @StartNode
    MyEvent event;

    @EndNode
    User    user;

    }

我在短期的junit测试中使用它们：

@Autowired
    private Neo4jTemplate template;

    @Transactional
    @Test
    public void saveEvent()
        {

        User user = new User();
        MyEvent event = new MyEvent();

        EventResponse response = new EventResponse();
        response.user = user;
        response.event = event;

        this.template.save(user);
        this.template.save(event);
        this.template.save(response);

        }

在Spring Data neo4j中使用RelationshipEntity保存Node的正确方法是什么？

1 个答案: