java - 没有 EntityManagerFactory 类型的合格 bean

Question

我正在运行一个 Spring Rest 应用程序，它是一个控制台应用程序。我正在使用嵌入 tomcat 7 的 spring-boot。

当我启动应用程序时，我得到堆栈跟踪并转储出来。根本原因如下:

Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined
        at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findDefaultEntityManagerFactory(PersistenceAnnotationBeanPostProcessor.jav
a:559)
        at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findEntityManagerFactory(PersistenceAnnotationBeanPostProcessor.java:515)
        at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor$PersistenceElement.resolveEntityManager(PersistenceAnnotationBeanPostProce
ssor.java:682)
        at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor$PersistenceElement.getResourceToInject(PersistenceAnnotationBeanPostProces
sor.java:655)
        at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:150)
        at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87)
        at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessPropertyValues(PersistenceAnnotationBeanPostProcessor.java:353)

        ... 22 more

这是我开始我的应用程序的地方:

import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.SpringApplication;
import org.springframework.context.annotation.ComponentScan;

@ComponentScan
@EnableAutoConfiguration
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

这是我的/src/main/resources/spring-config.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:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
           http://www.springframework.org/schema/aop
           http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
           http://www.springframework.org/schema/context
           http://www.springframework.org/schema/context/spring-context-3.0.xsd
           http://www.springframework.org/schema/tx  
           http://www.springframework.org/schema/tx/spring-tx.xsd">

    <context:component-scan base-package="com.mydomain.orm" />

    <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="persistenceXmlLocation" value="classpath:/persistence.xml" />
        <property name="persistenceUnitName" value="userPersistenceUnit" />
        <property name="dataSource" ref="dataSource" />
        <property name="jpaVendorAdapter" ref="jpaVendorAdapter" />
        <property name="jpaDialect" ref="jpaDialect" />
    </bean>

    <bean id="jpaVendorAdapter" class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
        <property name="database" value="POSTGRESQL" />
        <property name="databasePlatform" value="org.hibernate.dialect.PostgreSQLDialect" />
    </bean>

    <bean id="jpaDialect" class="org.springframework.orm.jpa.vendor.HibernateJpaDialect" />

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

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

    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="org.postgresql.Driver" />
        <property name="url" value="jdbc:postgresql://localhost:5432/mydb" />
        <property name="username" value="myuser" />
        <property name="password" value="" />
    </bean>
</beans> 

这是我的 DAO:

@Repository("userDao")
@Transactional(propagation = Propagation.REQUIRED)
public class UserDAO {

    private static final String SELECT_QUERY = "select u from users";

    @PersistenceContext
    private EntityManager entityManager;

    public EntityManager getEntityManager() {
        return entityManager;
    }

    public void setEntityManager(EntityManager entityManager) {
        this.entityManager = entityManager;
    }

    public void insert(User user) {
        entityManager.persist(user);
    }

    public User load(int id) {
        return entityManager.find(User.class, id);
    }

    public List<User> selectAll() {
        Query query = entityManager.createQuery(SELECT_QUERY);
        @SuppressWarnings("unchecked")
        List<User> users = (List<User>) query.getResultList();
        return users;
    }
}

还有我的/src/main/persistence.xml:

<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="1.0">
    <persistence-unit name="userPersistenceUnit" transaction-type="RESOURCE_LOCAL" >
        <class>com.mydomain.orm.User</class>
    </persistence-unit>
</persistence> 

Answer 1

如果您要使用@PersistenceContext，则需要set up persistence.xml for your use case ，因为该注释有效地告诉 Spring，“使用 Java EE 方式设置 JPA，而不是 Spring/Hibernate 方式。”请记住Tomcat is not a Java EE container, so it may not work right. 。不过，Spring Boot 是相当新的，因此可能有一种方法可以做到这一点，但尚未有详细记录。

我将从设置 persistence.xml 开始，看看会发生什么。