Spring 创建Hibernate SessionFactory bean时出错

我在尝试运行应用程序时遇到了这个错误，我认为它在抱怨创建sessionFactory时出错，注入依赖项失败。我一整天都在努力修理它。多谢各位

这是从控制台输出的错误

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'userDao': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.hibernate.SessionFactory com.donah.web.dao.UserDao.sessionFactory; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in class path resource [com/donah/web/config/dao-context.xml]: Invocation of init method failed; nested exception is org.hibernate.AnnotationException: No identifier specified for entity: com.donah.web.dao.Users
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:288)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1116)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)

Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.hibernate.SessionFactory com.donah.web.dao.UserDao.sessionFactory; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in class path resource [com/donah/web/config/dao-context.xml]: Invocation of init method failed; nested exception is org.hibernate.AnnotationException: No identifier specified for entity: com.donah.web.dao.Users
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:514)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:285)
    ... 22 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in class path resource [com/donah/web/config/dao-context.xml]: Invocation of init method failed; nested exception is org.hibernate.AnnotationException: No identifier specified for entity: com.donah.web.dao.Users
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1482)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:521)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:458)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:295)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:223)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:292)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:910)!

这是UserDao类

@Repository
@Component("userDao")
public class UserDao {

    public UserDao(){}

    @Autowired
    private SessionFactory sessionFactory;

    private Session session() {
        return sessionFactory.getCurrentSession();
    }

    public void createUser(Users user) {
        session().save(user);
    }

    public Users getUser(String username) {

        Criteria crit = session().createCriteria(Users.class);
        crit.add(Restrictions.idEq(username));
        return (Users) crit.uniqueResult();
    }

org.hibernate.AnnotationException:未为实体com.donah.web.dao.Users指定标识符

这就是你问题的原因。这意味着用户实体顺便说一句，在名为dao的包中有JPA实体没有标识符是很奇怪的。每个JPA实体都必须有一个标识符

基于Restrictions.idEqusername，我猜您使用username作为主键，因此应该在Users实体中的username属性上添加注释

例如，可以找到更多细节

@Entity
@Table(name="users")
public class Users {
    @Id
    private String username;

    // other properties and getters/setters
}