Question

我整天都在苦苦挣扎，但尚未找到解决方案。

我有一个简单的实体映射到数据库表：

@Entity
@Table(name = "PERSON")
public class Person implements Serializable {

// Attributes.    
@Id
@Column(name = "ID", unique = true, nullable = false)    
@GeneratedValue(strategy=GenerationType.AUTO)
private Integer id;

@Column(name = "NAME", nullable = false, length=50)      
private String name;

@Column(name = "ADDRESS", nullable = false, length=100)
private String address;

@Column(name = "TELEPHONE", nullable = false, length=10)
private String telephone;

@Column(name = "EMAIL", nullable = false, length=50)
private String email;

@OneToMany(cascade=CascadeType.ALL, fetch = FetchType.LAZY)
@JoinColumn(name="PERSON_ID")   
private List<Book> books;

// Constructors.
public Person() {
    this.id = 0;
    this.name = ("");
    this.address = ("");
    this.telephone = ("");
    this.email = ("");
    this.books = null;
}

此实体由Spring控制器管理，方法如下：

@RequestMapping(value = "/register", method = RequestMethod.POST)
public String post(@ModelAttribute("person") Person person, 
                   BindingResult bindingResult, 
                   SessionStatus sessionStatus,
                   Model model /* , 
                   HttpSession session */) throws DAOException {                  
    logger.info(PersonController.class.getName() + ".post() method called.");

    personValidator.validate(person, bindingResult);
    if (bindingResult.hasErrors()) {
        return "register";
    }
    else {

        // Write Person to database.
        personService.insert(person);

        // Set view.
        sessionStatus.setComplete();             
        return "options";            
    }
}

服务类是：

@Service("personService")
@Transactional
public class PersonService {

@Autowired 
PersonDAO personDAO;

public void insert(Person person) throws DAOException {
    personDAO.insert(person);
}

DAO如下：

@Repository("PersonDAO")
public class PersonDAOImpl implements PersonDAO {

@Autowired
private SessionFactory sessionFactory;
static final Logger logger = Logger.getLogger(PersonDAOImpl.class.getName()); 

@Override
public void insert(Person person) throws DAOException {
    logger.info(PersonDAOImpl.class.getName() + ".insert() method called.");

    Session session = sessionFactory.openSession();
    Transaction transaction = session.getTransaction();
    try {
        transaction.begin();
        session.save(person);
        transaction.commit();
    }
    catch(RuntimeException e) {
        transaction.rollback();
        throw new DAOException(e);
    }
    finally {
        session.close();
    }
}

当然，我的Spring servlet将所有内容绑定在一起：

<bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
    <property name="dataSource" ref="dataSource"></property>        
    <property name="hibernateProperties">
        <props>
           <prop key="hibernate.dialect">org.hibernate.dialect.DerbyDialect</prop>
           <prop key="hibernate.show_sql">true</prop>
           <prop key="hibernate.current_session_context_class ">thread</prop>

           <!-- What to do with the database schema. -->
           <prop key="hbm2ddl.auto">validate</prop>    
           <!-- validate:    validate the schema, makes no changes to the database.
                update:      update the schema.
                create:      creates the schema, destroying previous data.
                create-drop: drop the schema at the end of the session. -->                 
        </props>            
    </property>                    
</bean>

为什么我收到消息：

org.hibernate.MappingException: Unknown entity: library.model.Person

如果我尝试这样的话：

<property name="packagesToScan" value="library.model" /> 

<property name="annotatedClasses">
        <list>
            <value>library.model.Person</value>
        </list>
    </property>

目前我正在接受：

2014年6月15日下午10:50:58 org.apache.catalina.core.ApplicationContext log INFO：初始化Spring root WebApplicationContext 2014年6月15日 10:51:02 PM org.apache.catalina.core.StandardContext listenerStart SEVERE：将上下文初始化事件发送给侦听器的异常类的实例 org.springframework.web.context.ContextLoaderListener org.springframework.beans.factory.BeanCreationException：错误用名称＆＃39; personController创建bean＆＃39 ;:注入自动装配依赖失败;嵌套异常是 org.springframework.beans.factory.BeanCreationException：不能 autowire字段：library.services.PersonService library.controller.PersonController.personService;嵌套异常是 org.springframework.beans.factory.BeanCreationException：错误使用名称＆＃39; personService创建bean＆＃39 ;:注入自动装配依赖失败;嵌套异常是 org.springframework.beans.factory.BeanCreationException：不能 autowire字段：library.dao.PersonDAOImpl library.services.PersonService.personDAO;嵌套异常是 org.springframework.beans.factory.BeanCreationException：错误创建名为＆＃39; PersonDAOImpl＆＃39;：注入自动装配的bean 依赖失败;嵌套异常是 org.springframework.beans.factory.BeanCreationException：不能 autowire字段：org.hibernate.SessionFactory library.dao.PersonDAOImpl.sessionFactory;嵌套异常是 org.springframework.beans.factory.BeanCreationException：错误创建名为＆＃39; sessionFactory＆＃39;的bean在ServletContext中定义 resource [/WEB-INF/library-servlet.xml]：调用init方法失败;嵌套异常是java.lang.NoClassDefFoundError： javax / persistence / NamedStoredProcedureQuery at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues（AutowiredAnnotationBeanPostProcessor.java:292）在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean（AbstractAutowireCapableBeanFactory.java:1185）在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean（AbstractAutowireCapableBeanFactory.java:537）在 org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean（AbstractAutowireCapableBeanFactory.java:475）在 org.springframework.beans.factory.support.AbstractBeanFactory $ 1.getObject（AbstractBeanFactory.java:304）在 org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton（DefaultSingletonBeanRegistry.java:228）在 org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean（AbstractBeanFactory.java:300）在 org.springframework.beans.factory.support.AbstractBeanFactory.getBean（AbstractBeanFactory.java:195）在 org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons（DefaultListableBeanFactory.java:700）在 org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization（AbstractApplicationContext.java:760）在 org.springframework.context.support.AbstractApplicationContext.refresh（AbstractApplicationContext.java:482）在 org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext（ContextLoader.java:403）在 org.springframework.web.context.ContextLoader.initWebApplicationContext（ContextLoader.java:306）在 org.springframework.web.context.ContextLoaderListener.contextInitialized（ContextLoaderListener.java:106）在 org.apache.catalina.core.StandardContext.listenerStart（StandardContext.java:4681）在 org.apache.catalina.core.StandardContext $ 1.call（StandardContext.java:5184）在 org.apache.catalina.core.StandardContext $ 1.call（StandardContext.java:5179）在java.util.concurrent.FutureTask.run（FutureTask.java:266）at java.util.concurrent.ThreadPoolExecutor.runWorker（ThreadPoolExecutor.java:1142）在 java.util.concurrent.ThreadPoolExecutor中的$ Worker.run（ThreadPoolExecutor.java:617）在java.lang.Thread.run（Thread.java:744）

Answer 1

尝试更换：

<property name="annotatedClasses">
    <list>
        <value>library.model.Person</value>
    </list>
</property>

使用：

<property name="packagesToScan">
   <list>
       <value>library.model</value>
    </list>
</property>

在你的sessionFactory属性中。

如果您收到错误消息，说明该物业＆＃34; packagesToScan＆＃34;找不到，那么你应该将spring-orm库添加到你的项目中。如果你正在使用maven，那么你可以添加：

<dependency>
   <groupId>org.springframework</groupId>
   <artifactId>spring-orm</artifactId>
   <version>YOUR SPRING VERSION HERE</version>
</dependency>

org.hibernate.MappingException：未知实体：library.model.Person

1 个答案: