@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
我们为什么要使用这些注解?我想知道它是否会自动递增我的表id值。(GenerationType.IDENTITY) 除了这种类型,还有其他类型吗?当我们使用这个注解时实际上发生了什么?
public class Author extends Domain
{
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name = "id")
private Integer id;
@Basic(optional = false)
@Column(name = "name")
private String name;
@Column(name = "address")
private String address;
@OneToMany(cascade = CascadeType.ALL, mappedBy = "authorId")
private List<Book>
bookList;
public Author()
{
setServiceClassName("wawo.tutorial.service.admin.AuthorService");
}
}
*有必要扩展Domain抽象类吗?它有什么用处?