二、一对多(单向)
Bean:
public class Car implements Serializable{ private int id ; private String name ; private User user ; .... } public class User implements Serializable { private int id ; private String name ; private Set<Car> cars ; .... }
xml配置:
Car.hbm.xml: <class name = "Car"> <!-- id是来配置主键 name是类中的哪个属性和主键映射 generator:表示主键的生成策略 --> <id name = "id"> <generator class="native" /> </id> <!-- property是用来把类中的属性和表的字段做一一对应 --> <property name="name" /> </class> User.hbm.xml: <class name = "User"> <!-- id是来配置主键 name是类中的哪个属性和主键映射 generator:表示主键的生成策略 --> <id name = "id"> <generator class="native" /> </id> <!-- property是用来把类中的属性和表的字段做一一对应 --> <property name="name" /> <set name="cars" cascade="all"> <key column="uid" /> <one-to-many class="Car"/> </set> </class>
annotation配置:
@Entity public class Car implements Serializable{ @Id @GeneratedValue public int getId() { return id; } } @Entity public class User implements Serializable { @Id @GeneratedValue public int getId() { return id; } @OneToMany(cascade=CascadeType.ALL) @JoinColumn(name="uid") public Set<Car> getCars() { return cars; } }
时间: 2024-10-24 21:55:10