Hibernate实现单向多对一

一篇文章可以有多个作者，这就是一个简单的一对多关系。

首先配置pojo

        <mapping class="qdm.entity.manytoone.Article" />
        <mapping class="qdm.entity.manytoone.Author" />

/*
多对一中 “多”端的配置
*/
@Entity
@Table(name="tb_author")
public class Author {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private int id;
    private String name;

    @ManyToOne
    @Cascade(value = CascadeType.SAVE_UPDATE)
    @JoinColumn
    private Article article;

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

    public Author() {
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Article getArticle() {
        return article;
    }

    public void setArticle(Article article) {
        this.article = article;
    }
}

@Entity
@Table(name="tb_article")
public class Article {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private int id;
    private String name;

    public Article() {
    }

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

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }
}

和一对多类似

在一对多种 存储多方用的是list

在多对一中 存储一方用的是实体类

测试代码

public static void manyToOneTest()
    {
        Article article=new Article("海底几万里");
        Author author1=new Author("你");
        Author author2=new Author("我");
        Author author3=new Author("他");

        author1.setArticle(article);
        author2.setArticle(article);
        author3.setArticle(article);
        Session session= Hibernate.getSession();
        session.beginTransaction();
        session.save(author1);
        session.save(author2);
        session.save(author3);
        session.getTransaction().commit();
    }

 

运行结果可以看出也可级联添加，多对一配置成功