Question

我正在尝试重构我的一些数据模型，但我遇到了一个我不明白的问题。

最初我有一个由3个实体类组成的简单数据模型，看起来像这样：

@Entity
public final class Teacher {
  @Id
  private Long id;
  private String primarySubject;

  public Teacher() {}

  public Teacher(String primarySubject) {
    this.primarySubject = primarySubject;
  }

  //getters & setters
}

@Entity
public final class Student {
  @Id
  private String username;
  @Load
  @Index
  private Ref<Teacher> homeRoomTeacher;

  public Student() {}

  public Student(String username, Teacher teacher) {
    this.username = username;
    homeRoomTeacher = Ref.create(teacher);
  }

  //getters & setters
}

@Entity
public final class School {
  @Id
  private String name;
  @Load
  private Set<Ref<Teacher>> teachers;
  @Load
  private Set<Ref<Student>> students;

  public School() {}

  public School(String name) {
    this.name = name;
  }

  //getters & setters
}

这一切都很好。

但是我们决定直接嵌入实体而不是Refs ...

会更有用

@Entity
@Embed
public final class Teacher {
  @Id
  private Long id;
  private String primarySubject;

  public Teacher() {}

  public Teacher(String primarySubject) {
    this.primarySubject = primarySubject;
  }

  //getters & setters
}

@Entity
@Embed
public final class Student {
  @Id
  private String username;
  @Index
  private Ref<Teacher> homeRoomTeacher;

  public Student() {}

  public Student(String username, Teacher teacher) {
    this.username = username;
    homeRoomTeacher = Ref.create(teacher);
  }

  //getters & setters
}

@Entity
public final class School {
  @Id
  private String name;
  private Set<Teacher> teachers;
  private Set<Student> students;

  public School() {}

  public School(String name) {
    this.name = name;
  }

  //getters & setters
}

在进行这些更改之后，在我们的测试设置方法中注册School类期间，所有的junit测试都开始失败并出现AssertionError，如下所示：

  @Before
  public void setUp() throws Exception {
    helper = new LocalServiceTestHelper(new LocalDatastoreServiceTestConfig());
    helper.setUp();
    ObjectifyService.register(Teacher.class);
    ObjectifyService.register(Student.class);
    ObjectifyService.register(School.class);

    // more setup
  }

AssertionError不会出现，直到注册School类的行，并且根据方法抛出堆栈跟踪＆＃34; com.googlecode.objectify.impl.translate.CreateContext.enterCollection＆＃34;但我不确定如何修复它。

有没有人有任何想法？

Answer 1

我怀疑你得到的错误是因为你正在尝试注册一个你用@Embed注释的类。

客观化文档明确指出@Embed类不必注册 - 也许这就是问题的原因。

另外，我对此并不是100％肯定，但我认为你在嵌入式课程中不需要@Id。

我建议您进行以下更改：

@Embed
public final class Teacher {
  @Id
  private Long id;
  private String primarySubject;

  public Teacher() {}

  public Teacher(String primarySubject) {
    this.primarySubject = primarySubject;
  }

  //getters & setters
}

@Embed
public final class Student {
  @Id
  private String username;
  @Index
  private Ref<Teacher> homeRoomTeacher;

  public Student() {}

  public Student(String username, Teacher teacher) {
    this.username = username;
    homeRoomTeacher = Ref.create(teacher);
  }

  //getters & setters
}

@Before
public void setUp() throws Exception 
{
    helper = new LocalServiceTestHelper(new LocalDatastoreServiceTestConfig());
    helper.setUp();
    ObjectifyService.register(School.class);

    // more setup
}

希望这有帮助！

使用ObjectifyService.register时获取AssertionError

1 个答案: