休眠未知实体（不缺少@entity或import javax.persistence.entity）
我有一个非常简单的课程：休眠未知实体（不缺少@entity或import javax.persistence.entity）,java,hibernate,Java,Hibernate,我有一个非常简单的课程： import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.GeneratedValue; import javax.persistence.GenerationType; import javax.persistence.Id; import javax.persistence.Table; @Entity @Table(name = "user
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name = "users")
public class User {
@Column(name = "firstName")
private String firstName;
@Column(name = "lastName")
private String lastName;
@Column(name = "email")
private String email;
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
@Column(name = "id")
private long id;
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
}
public class Main {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
HibernateUtil.buildSessionFactory();
Session session = HibernateUtil.getSessionFactory().getCurrentSession();
session.beginTransaction();
User u = new User();
u.setEmail("david@hello.co.uk");
u.setFirstName("David");
u.setLastName("Gray");
session.save(u);
session.getTransaction().commit();
System.out.println("Record committed");
session.close();
}
}
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;
public class HibernateUtil {
private static SessionFactory sessionFactory;
private static ServiceRegistry serviceRegistry;
public static SessionFactory buildSessionFactory() {
try {
// Create the SessionFactory from hibernate.cfg.xml
Configuration configuration = new Configuration();
configuration.configure();
serviceRegistry = new ServiceRegistryBuilder().applySettings(configuration.getProperties()).buildServiceRegistry();
return new Configuration().configure().buildSessionFactory(serviceRegistry);
} catch (Throwable ex) {
// Make sure you log the exception, as it might be swallowed
System.err.println("Initial SessionFactory creation failed." + ex);
throw new ExceptionInInitializerError(ex);
}
}
public static SessionFactory getSessionFactory() {
sessionFactory = new Configuration().configure().buildSessionFactory(serviceRegistry);
return sessionFactory;
}
}
com.mysql.jdbc.Driver
jdbc：mysql://localhost/ssme
根
我的密码
1.
org.hibernate.dialogue.mysqldialogue
线
org.hibernate.cache.NoCacheProvider
真的
更新
persistence.xmlhibernate.cfg.xmlhibernate.cfg.xml<mapping class="com.entity.Users"/>
您应该使用
注释配置配置configuration.addAnnotatedClass(User.class);
将您的类添加到映射类列表中。在
hibernate.cfg.xml<mapping class="org.assessme.com.entity.User" />
考虑使用所述的
注释配置
您可以使用它的addClass（User.class）
方法，或者如果要持久化多个实体，则可以使用addPackage（“org.assessme.com.entity”）
方法
你正在用这个HibernateUtil
类重新发明轮子。考虑使用Spring，这样你就可以利用一些类似于它的代码> AnnotationSessionFactoryBean < /Cord>。 < P>我忘记把HBMXML映射添加到我的CFG.XML文件中。我一添加它，这个异常就消失了
<mapping resource="com/mycompany/backend/hibernate/CServiceCenters.hbm.xml" />
将下面的行添加到hibernate.cfg.xml
<mapping class="fully qualified Entity class name"/>
我也遇到了类似的问题，但当我用方言添加MySQL版本时，问题得到了解决。
org.hibernate.dialogue.mysql8dialogue
兼容性似乎有问题。啊，我应该在我的hibernateutil中这样做吗？你认为在一个类中完成这一切是最好的做法吗？取决于项目的规模。如果您只有几个映射类，则可以在HibernateUtil
中执行此操作。对于更大的项目，您可以使用反射将特定包的所有类添加到hibernate，也可以使用映射配置文件。