Java 不带joincolumn/jointable的Hibbernate映射映射
尝试Hibernate 4.3文档“7.2.2.2.Maps”中的示例,其中我有两个实体:Java 不带joincolumn/jointable的Hibbernate映射映射,java,hibernate,dictionary,mapping,persistence,Java,Hibernate,Dictionary,Mapping,Persistence,尝试Hibernate 4.3文档“7.2.2.2.Maps”中的示例,其中我有两个实体: @Entity public class Order { @Id @GeneratedValue private Integer id; String number; @ManyToOne private Customer customer; //getters/setters } @Entity public class Customer
@Entity
public class Order {
@Id
@GeneratedValue
private Integer id;
String number;
@ManyToOne
private Customer customer;
//getters/setters
}
@Entity
public class Customer {
@Id
@GeneratedValue
private Integer id;
@OneToMany(mappedBy = "customer", cascade = CascadeType.ALL)
@MapKey(name = "number")
private Map<String, Order> orders;
//getters/setters
}
怎么了?您没有在任何地方初始化订单的
number
属性,因为typeString
的默认值是null
,因此您在db中得到了一个空值。我正在重新考虑这个功能,我错了。如何正确地说。此功能用于加载贴图,但不用于自动填充属性。
session.beginTransaction();
Map<String, Order> map = new HashMap<>();
map.put("0", new Order());
map.put("1", new Order());
map.put("2", new Order());
map.put("3", new Order());
Customer customer = new Customer();
customer.setOrders(map);
session.save(customer);
session.getTransaction().commit();