getSession Neo4j [NullPointerException：null]

Question

我当前的配置

class Neo4jSessionFactory (implicit inj: Injector) extends Injectable  {
  val neo4jHost           = inject [String] (identified by "neo4j.server.host")
  val neo4jPort           = inject [Integer] (identified by "neo4j.server.port")
  val neo4jDb             = inject [String] (identified by "neo4j.server.db")
  val neo4jUser           = inject [String] (identified by "neo4j.server.user")
  val neo4jPass           = inject [String] (identified by "neo4j.server.pass")

  def neo4jServer() : Neo4jServer = {
    return new RemoteServer("http://localhost:7474", "neo4j", "neo4j");
  }

  def getNeo4jConfiguration : Configuration = {
    var config = new Configuration
    config.driverConfiguration()
          .setDriverClassName("org.neo4j.ogm.drivers.http.driver.HttpDriver")
          .setURI("http://neo4j:neo4j@localhost:7474")
    return config
  }

  def getNeo4jSessionFactory: SessionFactory = {
    System.setProperty("username", "neo4j")
    System.setProperty("password", "neo4j")
    var config = getNeo4jConfiguration
    return new SessionFactory(getNeo4jConfiguration,"domain")
  }

 def getNeo4jTemplate : Neo4jOperations = {
     return new Neo4jTemplate(getNeo4jSession)
 }

 def getNeo4jSession : Session = {
    return getNeo4jSessionFactory.openSession
  }

和我的Controller类

class Application (implicit inj : Injector) extends Controller with Injectable {
  val neo4jService = inject[Neo4jSessionFactory]
  val session = neo4jService.getNeo4jTemplate

  def insertStudentNeo4j(name: String, age: Int) = Action { implicit request =>
    val test = new domain.Student
    test.name=Option(name).getOrElse("default").toString
    test.age=Option(age).getOrElse(0).toInt
    session.save(test)
    // var jason = MyJsonUtil.convertStudentToJsonOrig(test)
    Ok(Json.obj("Name:" -> name))
  }

当我尝试将对象保存到neo4j时，它返回NullPointerException并尝试println(session)和println(test)它们都不为空，我仍然想知道原因是什么？

这是我的学生班

@NodeEntity
class Student extends Entity {
    var name: String = _
    var age: Int = _
    var txt: String = _

  def this(name: String, age: Int, txt: String) = {
    this()
    this.name=name
    this.age=age
    this.txt=txt
  }
}

和我的实体类，其中包含一个不分配值的graphId。

abstract class Entity {
  @GraphId
  @BeanProperty
  var graph_id: java.lang.Long = _

  override def equals(o: Any): Boolean = o match {
    case other: Entity => other.graph_id.equals(this.graph_id)
    case _ => false
  }
}