这只是我在 JPA 上的第一个演示,它非常简单,以至于这个错误让我发疯:(
数据库(postgresql)
CREATE TABLE "Order"
(
"Id" integer NOT NULL,
"DateOf" timestamp with time zone,
"Description" text,
CONSTRAINT "PK_Id" PRIMARY KEY ("Id" )
)
CREATE TABLE "LineItem"
(
"Id" oid NOT NULL,
"OrderId" integer,
"Cost" money,
CONSTRAINT "LineItem_Id" PRIMARY KEY ("Id" ),
CONSTRAINT "LineItem_OrderId_fkey" FOREIGN KEY ("OrderId")
REFERENCES "Order" ("Id") MATCH SIMPLE
ON UPDATE NO ACTION ON DELETE NO ACTION
)
模型
@Entity
@Table(name="\"Order\"")
@XmlRootElement(name="Order")
public class Order implements Serializable {
private static final long serialVersionUID = 1L;
@Id @GeneratedValue
@Column(name="\"Id\"")
public int Id;
@Column(name="\"DateOf\"")
public java.util.Date DateOf;
@Column(name="\"Description\"")
public String Description;
@OneToMany(cascade=CascadeType.REMOVE, mappedBy="order")
public List<LineItem> Items;
}
@Entity
@Table(name="\"LineItem\"")
public class LineItem implements Serializable {
private static final long serialVersionUID = 1L;
@Id @GeneratedValue
@Column(name="\"Id\"")
public int Id;
@ManyToOne(cascade=CascadeType.REMOVE)
@JoinColumn(name="\"OrderId\"", referencedColumnName="Id")
public Order order;
}
中层
EntityManagerFactory entityManagerFactory = Persistence
.createEntityManagerFactory("store");
EntityManager entityManager = entityManagerFactory
.createEntityManager();
Query select = entityManager.createQuery("select t from Order t");
例外
org.hibernate.MappingException: Unable to find column with logical name: Id in org.hibernate.mapping.Table(Order) and its related supertables and secondary tables
org.hibernate.cfg.Ejb3JoinColumn.checkReferencedColumnsType(Ejb3JoinColumn.java:552)
org.hibernate.cfg.BinderHelper.createSyntheticPropertyReference(BinderHelper.java:257)
org.hibernate.cfg.ToOneFkSecondPass.doSecondPass(ToOneFkSecondPass.java:116)
org.hibernate.cfg.Configuration.processEndOfQueue(Configuration.java:1525)
org.hibernate.cfg.Configuration.processFkSecondPassInOrder(Configuration.java:1446)
org.hibernate.cfg.Configuration.secondPassCompile(Configuration.java:1351)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1737)
org.hibernate.ejb.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:94)
org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:905)
org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:890)
org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:57)
javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:63)
javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:47)
rest.Orders.List(Orders.java:37)