无法在休眠中使用 jpa 创建实体管理器工厂

Question

我正在使用 jpa 、 hibernate 和 eclipse 来构建一个 spring mvc 应用程序。以下是我的控制器：

package com.something.controller;

import java.util.ArrayList;
import java.util.List;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import javax.persistence.TypedQuery;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.bind.annotation.RestController;

import com.drc.model.Project;
import com.drc.service.ProjectService;

@RestController("projectController")
@RequestMapping("/project")
public class ProjectController {

    @Autowired
    private ProjectService projectService;

    @RequestMapping(value = "/{projectName}", method = RequestMethod.GET)
    public String createProject (@PathVariable String projectName)
    {

        EntityManagerFactory emf = Persistence.createEntityManagerFactory("punit");
        EntityManager em = emf.createEntityManager();       
        TypedQuery<Project> query= em.createQuery("from project where name=:projectName",Project.class);
        List<Project> results= query.getResultList();

         if(results.size()>0)
         {
             return "there are entries";

         }

         else
         {
             return "there are no entries";
         }


    }

这是我的 jpaContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:jpa="http://www.springframework.org/schema/data/jpa"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.3.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">

    <context:annotation-config />
    <context:component-scan base-package="com.drc" />

    <jpa:repositories base-package="com.drc.repository"/>

    <bean
        class="org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor" />

    <bean id="entityManagerFactory"
        class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="persistenceUnitName" value="punit" />
        <property name="dataSource" ref="dataSource" />
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
                <property name="showSql" value="true" />
            </bean>
        </property>

        <property name="jpaPropertyMap">
            <map>
                <entry key="hibernate.dialect" value="org.hibernate.dialect.MySQL5InnoDBDialect"></entry>
                <entry key="hibernate.hbm2ddl.auto" value="update" />
                <entry key="hibernate.format_sql" value="true" />
            </map>
        </property>
    </bean>

    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory" />
    </bean>

    <tx:annotation-driven transaction-manager="transactionManager" />

    <bean id="dataSource"
        class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver" />
        <property name="url"
            value="jdbc:mysql://localhost:3306/apecadprojects?autoReconnect=true" />
        <property name="username" value="root" />
        <property name="password" value="root" />
    </bean>

</beans>



Whenever i browse to the page say localhost:8080/projectname/project/myname i get the following error

如您所见，它不允许我创建 EntityManagerFactory..为什么？？？

下面是我的persistence.xml

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd" version="2.0">

    <persistence-unit name="punit">
    <provider>org.hibernate.jpa.PersistenceProvider</provider>

    </persistence-unit>
</persistence>

我做错了什么？？

更新好现在尝试了几个小时后我得到以下错误可以请有人指出问题是什么吗？我的 hql 错了吗？？

Answer 1

确保 persistence.xml 位于类路径的 META-INF 目录中。

Answer 2

您似乎没有在持久性 xml 中添加类名。

在你的持久化 xml 中添加这个

<class>yourpackage.Project</class>

并在您的实体管理器 bean 中添加属性

<property name="persistenceXmlLocation" value="classpath:META-INF/persistence.xml" />