使用spring框架部署gwt应用程序时，上下文初始化失败

Question

您好我正在尝试将spring与jpa集成为gwt客户端的后端。是第一次这样做而且无法解决这个错误

15:56:43,315 ERROR [org.springframework.web.context.ContextLoader] - Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'surevyDAOImpl': Injection of persistence dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation of init method failed; nested exception is java.lang.IllegalStateException: JPA PersistenceProvider returned null EntityManagerFactory - check your JPA provider setup!
    at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessPropertyValues(PersistenceAnnotationBeanPostProcessor.java:341)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1074)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:580)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425)
    at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:276)
    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:197)
    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:47)
    at org.mortbay.jetty.handler.ContextHandler.startContext(ContextHandler.java:543)
    at org.mortbay.jetty.servlet.Context.startContext(Context.java:136)
    at org.mortbay.jetty.webapp.WebAppContext.startContext(WebAppContext.java:1220)
    at org.mortbay.jetty.handler.ContextHandler.doStart(ContextHandler.java:513)
    at org.mortbay.jetty.webapp.WebAppContext.doStart(WebAppContext.java:448)
    at com.google.gwt.dev.shell.jetty.JettyLauncher$WebAppContextWithReload.doStart(JettyLauncher.java:468)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.handler.RequestLogHandler.doStart(RequestLogHandler.java:115)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at org.mortbay.jetty.handler.HandlerWrapper.doStart(HandlerWrapper.java:130)
    at org.mortbay.jetty.Server.doStart(Server.java:222)
    at org.mortbay.component.AbstractLifeCycle.start(AbstractLifeCycle.java:39)
    at com.google.gwt.dev.shell.jetty.JettyLauncher.start(JettyLauncher.java:672)
    at com.google.gwt.dev.DevMode.doStartUpServer(DevMode.java:509)
    at com.google.gwt.dev.DevModeBase.startUp(DevModeBase.java:1068)
    at com.google.gwt.dev.DevModeBase.run(DevModeBase.java:811)
    at com.google.gwt.dev.DevMode.main(DevMode.java:311)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'entityManagerFactory' defined in ServletContext resource [/WEB-INF/applicationContext.xml]: Invocation of init method failed; nested exception is java.lang.IllegalStateException: JPA PersistenceProvider returned null EntityManagerFactory - check your JPA provider setup!
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1420)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:519)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190)
    at org.springframework.orm.jpa.EntityManagerFactoryUtils.findEntityManagerFactory(EntityManagerFactoryUtils.java:98)
    at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findNamedEntityManagerFactory(PersistenceAnnotationBeanPostProcessor.java:510)
    at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findEntityManagerFactory(PersistenceAnnotationBeanPostProcessor.java:492)
    at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor$PersistenceElement.resolveEntityManager(PersistenceAnnotationBeanPostProcessor.java:656)
    at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor$PersistenceElement.getResourceToInject(PersistenceAnnotationBeanPostProcessor.java:629)
    at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:156)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:84)
    at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessPropertyValues(PersistenceAnnotationBeanPostProcessor.java:338)
    ... 31 more
Caused by: java.lang.IllegalStateException: JPA PersistenceProvider returned null EntityManagerFactory - check your JPA provider setup!
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:310)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1477)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1417)
    ... 45 more

我一直在使用以下文件： web.xml中：

<!-- Default page to serve -->
  <welcome-file-list>
    <welcome-file>MobiOffer_GWT.html</welcome-file>
  </welcome-file-list>

   <context-param>
        <param-name>log4jConfigLocation</param-name>
        <param-value>/WEB-INF/log4j.properties</param-value>
    </context-param>
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>
            /WEB-INF/applicationContext.xml
        </param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
    </listener>
     <filter>
        <filter-name>OpenEntityManagerInViewFilter</filter-name>
        <filter-class>org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter</filter-class>
        <init-param>
            <param-name>entityManagerFactoryBeanName</param-name>
            <param-value>entityManagerFactory</param-value>
        </init-param>
    </filter>

    <filter-mapping>
        <filter-name>OpenEntityManagerInViewFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    <listener>
        <listener-class>
            org.springframework.web.context.ContextLoaderListener
        </listener-class>
    </listener>

  <servlet>
     <servlet-name>rest-json-api</servlet-name>
     <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
     <load-on-startup>2</load-on-startup>
  </servlet>
  <servlet-mapping>
     <servlet-name>rest-json-api</servlet-name>
     <url-pattern>/restServices/*</url-pattern>
  </servlet-mapping>

  <servlet>
      <servlet-name>gwtDispatcher</servlet-name>
      <servlet-class>org.gwtrpcspring.RemoteServiceDispatcher</servlet-class>
  </servlet>
  <servlet-mapping>
      <servlet-name>gwtDispatcher</servlet-name>
      <url-pattern>/mobioffer_gwt/*</url-pattern>
  </servlet-mapping>
</web-app>

我在上面的web.xml文件中提到的rest-json-api-servlet.xml文件是：

 <!-- auto scan annotations -->
    <context:component-scan base-package="com.reva.mobioffer.services"/>


    <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
        <property name="messageConverters">
            <list>
                <ref bean="jsonHttpMessageConverter"/>
            </list>
        </property>
    </bean>

    <bean id="handlerMapping" class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping" />


    <bean id="jsonHttpMessageConverter"
          class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"/>

    <bean class="com.reva.mobioffer.views.MyContentNegotiatingViewResolver">
        <property name="mediaTypes">
            <map>
                <entry key="json" value="application/json"/>
            </map>
        </property>
        <property name="defaultContentType" value="application/json"/>
        <property name="defaultViews">
            <list>
                <bean class="com.reva.mobioffer.views.JSONView"/>
            </list>
        </property>
    </bean>

我也在使用applicationContext.xml文件，但我不确定这个xml文件的用途是什么（我可以看到通过它提到了jpa信息）

<context:component-scan base-package="com.reva.mobioffer.domain"/>

    <context:annotation-config/>

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

    <bean id="entityManagerFactory"
          class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean">
        <property name="persistenceUnitName" value="mobioffer"/>
    </bean>
    <bean id="persistenceUnitManager"
          class="org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager">
        <property name="persistenceXmlLocation">
            <value>classpath:META-INF/persistence.xml</value>
        </property>
    </bean>

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

    <bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping"/>

    <!-- Transaction manager for a single EntityManagerFactory (alternative to JTA) -->
    <bean id="transactionManager"
          class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory"/>
    </bean>
 <bean class="org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor"/>

这也是一个例外，因为无法为org.springframework.dao.annotation.PersistenceExceptionTranslationPostProcessor＃0创建bean＃0

persistance.xml文件位于META-INF文件中：

<persistence-unit name="mobioffer" transaction-type="RESOURCE_LOCAL">
        <provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
        <class>com.reva.mobioffer.domain.entity.Survey</class>
        <class>com.reva.mobioffer.domain.entity.SurveyLog</class>
        <class>com.reva.mobioffer.domain.entity.SurveyLogPK</class>
        <class>com.reva.mobioffer.domain.entity.SurveyQuestion</class>
        <class>com.reva.mobioffer.domain.entity.SurveyQuestionOptionMap</class>
        <class>com.reva.mobioffer.domain.entity.SurveyQuestionOptionMapPK</class>
        <class>com.reva.mobioffer.domain.entity.SurveyQuestionOption</class>
        <class>com.reva.mobioffer.domain.entity.SurveyQuestionOptionPK</class>
        <class>com.reva.mobioffer.domain.entity.SurveyQuestionResponse</class>
        <class>com.reva.mobioffer.domain.entity.SurveyQuestionResponsePK</class>

                <property name="javax.persistence.jdbc.url" value="jdbc:mysql://localhost:4406/mobioffer" />
            <property name="javax.persistence.jdbc.user" value="root" />
            <property name="javax.persistence.jdbc.password" value="root" />
            <property name="javax.persistence.jdbc.driver" value="com.mysql.jdbc.Driver" />
        </properties>

    </persistence-unit>
</persistence>

我已经坚持了很长一段时间，但即使在极端搜索之后也无法找到解决方法。 感谢

Answer 1

如异常所示：

  

JPA PersistenceProvider返回null EntityManagerFactory - 检查您的JPA提供程序设置！

看起来您的JPA设置不正确。首先，我要确保您可以从运行此设备的设备连接到MySQL数据库。 MySQL具有细粒度的安全性，可以根据用户的来源锁定用户。还要确保用户可以访问数据库。

其次，我会确保拼写所有数据库名称，用户名等。同样，异常来自JPA设置，所以从那里开始。