Hibernate使用注解

基本注解

//entity表示需要实体化的实体类@Entity //实体类所对应的表@Table(name="t_book")public class Book {    //主键    @Id    //主键生成策略，auto相当于native    @GeneratedValue(strategy=GenerationType.AUTO)    @Column(name="book_id")    private int id;    @Column(name="book_name")    private String name;    @Column    private double price;    //不写@Colum就是默认列名字和属性一致    private String author;    private Date pubDate;/*set/get方法略*/

使用注解后*.hbm.xml不存在了所以在hiberntae.cfg.xml里面mapping改为

<mapping class="cn.siggy.pojo.Book" />

不再是resource

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多对一双向注解

//entity表示需要实体化的实体类@Entity //实体类所对应的表@Table(name="t_book")public class Book {    //主键    @Id    //主键生成策略    @GeneratedValue(strategy=GenerationType.AUTO)    @Column(name="book_id")    private int id;    @Column(name="book_name")    private String name;    @Column    private double price;    private String author;    private Date pubDate;    @ManyToOne(cascade=CascadeType.ALL)    @JoinColumn(name="category_id")    private Category catregory;}

@Entity@Tablepublic class Category {    @Id    @GeneratedValue(strategy=GenerationType.AUTO)//oracle比较麻烦，参考网上的例子    private int id;    private String name;    @OneToMany(mappedBy="category")    private Set<Book>  books=new HashSet<Book>();

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