java - 使用 Neo4j 查询的 Spring 数据

Question

请参阅以下实体。

Person Entity

@NodeEntity
public class Person {  

    @GraphId Long personId; 

    private String name; 

    private String surname;

    @Relationship(type = "ATTENDS", direction = Relationship.OUTGOING) 
    private Set<Event> events;

Attends Entity

@RelationshipEntity(type = "ATTENDS")
public class Attends {

    @GraphId
    private Long id;

    @StartNode
    private Person person;

    @EndNode
    private Event event;

    private Date attendingDate;

Event Entity

@NodeEntity
public class Event {

    @GraphId
    private Long eventId;

    private String eventName;

    @Relationship(type = "ATTENDS", direction = Relationship.INCOMING)
    private Set<Person> persons; 

Here is my API

/persons/{personId}/参加

我想返回一个包含与所提供的 ID 相关的所有对象的列表，在下面的示例中它将是一个事件列表。

[{
"attends":{
"attendsId":"1234",
"startDate":"98098098",
"endDate":"098098098",
event:{ "eventId":"1234", "name":"ComicCon" }
},
"attends":{
"attendsId":"1235",
"startDate":"984548098",
"endDate":"45454545",
event:{ "eventId":"1235", "name":"AWS Summit" }

}]

我尝试以下查询但没有得到结果，

List<Attends> findByPersonPersonId(Long personId);

那么如何通过查询得到这个结果呢？

请指导，谢谢。

Answer 1

@NodeEntity
public class Person {

    @GraphId Long id; 

    private String personId;

    private String name; 

    private String surname;

    @Relationship(type = "ATTENDS", direction = Relationship.OUTGOING) 
    private Set<Attends> attendedEvents =new HashSet<Attends>();
}

@NodeEntity
public class Event {

    @GraphId
    private Long id;

    private String eventId;

    private String eventName;

    @Relationship(type = "ATTENDS", direction = Relationship.INCOMING)
    private List<Attends> attendedEvents = new ArrayList<Attends>();
}


@RelationshipEntity(type = "ATTENDS")
public class Attends {

    @GraphId
    private Long id;

    private String attendId;

    @StartNode
    private Person person;

    @EndNode
    private Event event;

    private Date attendingDate;
}

@Repository
public interface PersonRepository  extends GraphRepository<Person>{

     Person findByPersonId(String personId);

}


public class PersonServiceTest extends AbstractTest{

    @Autowired
    PersonRepository personRepository;

    @Test
    public void save(){

        Person person = new Person();
        person.setName("Person1");
        person.setPersonId(UUID.randomUUID().toString());
        person.setSurname("Surname1");

        Event event1 = new Event();
        event1.setEventId(UUID.randomUUID().toString());
        event1.setEventName("Event1");

        Event event2 = new Event();
        event2.setEventId(UUID.randomUUID().toString());
        event2.setEventName("Event2");

        Attends attends1 = new Attends();
        attends1.setAttendId(UUID.randomUUID().toString());
        attends1.setAttendingDate(new Date());
        attends1.setPerson(person);
        attends1.setEvent(event1);

        Attends attends2 = new Attends();
        attends2.setAttendId(UUID.randomUUID().toString());
        attends2.setAttendingDate(new Date());
        attends2.setPerson(person);
        attends2.setEvent(event2);

        person.getAttendedEvents().add(attends1);
        person.getAttendedEvents().add(attends2);

        personRepository.save(person);


    }

    @Test
    public void get(){
        Person person = personRepository.findByPersonId("ebc17b4b-2270-4e78-ac68-87bce5444ef4");

        person.getAttendedEvents().forEach(attendedEvent -> {
            System.out.println(attendedEvent.getEvent());
        });

    }


}