Question

我正在使用Spring Boot和Neo4J 2.1.8，并创建了两个NodeEntities父和子。父类是

    @NodeEntity
    public class Parent{

        @GraphId
        @Indexed(indexName = "id", indexType = IndexType.FULLTEXT)
        private Long id;

        @RelatedTo(type=RelationType.IS_RELATED,direction=Direction.OUTGOING)
        @Fetch
        private Set<Child> children;


    }

并且子类是

@NodeEntity
public class Child{
        @GraphId
    private Long id;

    private String name;
}

parentRepo和childRepo类都扩展了GraphRepository

现在，当创建一个父对象并在其中设置子对象并调用parentRepo.save(parent)时，将创建父实体和子实体以及关系。

现在问题陈述是：

当父实体已经创建并且我这样做时

Child child= new Child()
...............
Parent parent=parentRepo.retriveParent(id);
parent.getChildren().add(child);
parentRepo.save(parent);

以下错误即将来临： -

com.sun.jersey.api.client.ClientHandlerException: java.net.SocketTimeoutException: Read timed out
    at com.sun.jersey.client.urlconnection.URLConnectionClientHandler.handle(URLConnectionClientHandler.java:149)
    at org.neo4j.rest.graphdb.UserAgent$1.handle(UserAgent.java:68)
    at com.sun.jersey.api.client.Client.handle(Client.java:648)
    at com.sun.jersey.api.client.WebResource.handle(WebResource.java:670)
    at com.sun.jersey.api.client.WebResource.access$200(WebResource.java:74)
    at com.sun.jersey.api.client.WebResource$Builder.put(WebResource.java:523)
    at org.neo4j.rest.graphdb.ExecutingRestRequest.put(ExecutingRestRequest.java:155)
    at org.neo4j.rest.graphdb.RestAPIImpl.setPropertiesOnEntity(RestAPIImpl.java:633)
    at org.neo4j.rest.graphdb.entity.RestEntity.flush(RestEntity.java:189)

Answer 1

好的我明白了。我没有打电话给parentRepo.save(parent) 我做的是

childRepo.save(child);
Parent parent=parentRepo.retriveParent(id);
parent.getChildren().add(child);

节点和关系已自动更新。无需明确调用parentRepo.save()

无法将具有@RelatedTo传出方向的NodeEntity与另一个节点一起保存

1 个答案: