java - hibernate 注释。如何注释？

Question

我正在 Java EE 中制作一个小型库项目。我创建了 3 个表格和类，其中包含作者、流派和书籍。现在我尝试使用 hibernate 连接它，但我不知道如何配置注释...请帮助我:)

图书表:

| id_book |作者 ID |标题 |流派_id |描述 |照片 |

流派表:

|流派_id |流派 |

作者表:

|作者 ID |作者|

结构简单:

bookTable.author_id -authorTable.author_id = ManyToMany

bookTable.genre_id -genreTable.genre_id = OneToOne

下面是我的 pojo 类:

预订

@Entity
@Table(name = "books")
public class Book implements Serializable{

    private static final long serialVersionUID = -5057364006691079475L;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "user_id")
    private Integer user_id;
    private Author author;
    private String description;
    private BookGenre genre;
    private String title;


    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public Integer getUser_id() {
        return user_id;
    }

    public void setUser_id(Integer user_id) {
        this.user_id = user_id;
    }

    public Author getAuthor() {
        return author;
    }

    public void setAuthor(Author author) {
        this.author = author;
    }

    public BookGenre getGenre() {
        return genre;
    }

    public void setGenre(BookGenre genre) {
        this.genre = genre;
    }

}

作者

@Entity
@Table(name = "author")
public class Author implements Serializable{

    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "author_id")
    private Integer author_id;

    @Column(name = "author")
    private String author;  

    public Integer getAuthor_id() {
        return author_id;
    }

    public void setAuthor_id(Integer author_id) {
        this.author_id = author_id;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }
}

类型

@Entity
@Table(name = "genre")
public class BookGenre implements Serializable{

    private static final long serialVersionUID = 1L;

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(name = "genre_id")
    private Integer genreId;

    @Column(name = "genre")
    private String genre;


    public Integer getGenreId() {
        return genreId;
    }
    public void setGenreId(Integer genreId) {
        this.genreId = genreId;
    }
    public String getGenre() {
        return genre;
    }
    public void setGenre(String genre) {
        this.genre = genre;
    }

}

Answer 1

应该是单向关联还是双向关联？看看这个例子:

https://howtoprogramwithjava.com/hibernate-manytomany-unidirectional-bidirectional/

它甚至使用您的实体名称:)