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我在代码中有以下实体和关系，

图书.java

@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
@ToString
@Entity
@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
public class Book {
  @Id
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  private Integer id;

  private String name;

  @OneToMany(mappedBy = "book", fetch = FetchType.LAZY)
  private Set<BookPublisher> bookPublishers = new HashSet<>();

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

BookPublisher.java

@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
@ToString
@Entity
@Table(name = "book_publisher")
public class BookPublisher {

  @EmbeddedId
  private BookPublisherId id;

  @ManyToOne(fetch = FetchType.LAZY, optional = false)
  @MapsId("bookId")
  @JoinColumn(name = "book_id")
  private Book book;

  @ManyToOne(fetch = FetchType.LAZY, optional = false)
  @MapsId("publisherId")
  @JoinColumn(name = "publisher_id")
  private Publisher publisher;

  @Column(name = "published_date")
  private Date publishedDate;

  public BookPublisher(Book book, Publisher publisher, Date publishedDate) {
    this.id = new BookPublisherId(book.getId(), publisher.getId());
    this.book = book;
    this.publisher = publisher;
    this.publishedDate = publishedDate;
  }
}

Publisher.java

@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
@ToString
@Entity
@JsonIdentityInfo(generator = ObjectIdGenerators.PropertyGenerator.class, property = "id")
public class Publisher {
  @Id
  @GeneratedValue(strategy = GenerationType.IDENTITY)
  private Integer id;

  private String name;

  @OneToMany(mappedBy = "publisher", fetch = FetchType.LAZY)
  private Set<BookPublisher> bookPublishers = new HashSet<>();

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

BookPublisherId.java

@Data
@Builder
@AllArgsConstructor
@NoArgsConstructor
@ToString
@Embeddable
public class BookPublisherId implements Serializable {
  @Column(name = "book_id")
  private Integer bookId;

  @Column(name = "publisher_id")
  private Integer publisherId;
}

问题 1： 插入按 Book、Publisher、BookPublisher 的顺序正常工作。但是 findAll() 不会返回任何存储库的结果，它会导致查询下面的语句总是循环的，使用：

select bookpublis0_.book_id as book_id1_1_0_, bookpublis0_.publisher_id as publishe2_1_0_, bookpublis0_.book_id as book_id1_1_1_, bookpublis0_.publisher_id as publishe2_1_1_, bookpublis0_.published_date as publishe3_1_1_ from book_publisher bookpublis0_ where bookpublis0_.book_id=?

怎么了？

问题2： 如何查询图书对象的Publisher ID =？具有以下对象结构？findBookByPublisherID("1")

{
  "book_id": "1",
  "publishers": [
   {
      "publisher_id": "1",
       ...
   },
   {
      "publisher_id": "2",
       ...
   }
]
}
4

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