从 Spring 访问 EJB 类

Question

我有一个使用 spring 在 Java 1.8 中构建并部署在 Tomcat 上的 Web 应用程序。 我们有一个使用 EJB 用 Ja​​va 1.4 编写的第三方库。

我的应用程序需要从我们的 Spring Web 应用程序访问第三方库中存在的方法。

到目前为止，我根据此链接完成了以下操作。 http://docs.spring.io/spring/docs/current/spring-framework-reference/html/ejb.html

在我的 servlet-context.xml 中，我添加了

<beans:bean id="myComponent"
       class="org.springframework.ejb.access.LocalStatelessSessionProxyFactoryBean">
        <beans:property name="jndiName" value="jndi/ejb/AssociateSessionEJB"/>
        <beans:property name="businessInterface" value="com.company.serviceImpl.MyComponent"/>
    </beans:bean>

 <beans:bean id="loginService" class="com.company.serviceImpl.LoginServiceImpl">
        <beans:property name="myComponent" ref="myComponent"/>
 </beans:bean>

我收到以下错误

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'loginService' defined in ServletContext resource [/WEB-INF/spring/appServlet/servlet-context.xml]: Cannot resolve reference to bean 'myComponent' while setting bean property 'myComponent'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'myComponent' defined in ServletContext resource [/WEB-INF/spring/appServlet/servlet-context.xml]: Invocation of init method failed; nested exception is javax.naming.NameNotFoundException: Name [jndi/ejb/AssociateSessionEJB] is not bound in this Context. Unable to find [jndi].
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:359)
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:108)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1481)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1226)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
    at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:187)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1208)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1048)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1018)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:570)
    ... 38 more
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'myComponent' defined in ServletContext resource [/WEB-INF/spring/appServlet/servlet-context.xml]: Invocation of init method failed; nested exception is javax.naming.NameNotFoundException: Name [jndi/ejb/AssociateSessionEJB] is not bound in this Context. Unable to find [jndi].
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1578)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:545)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:351)
    ... 52 more

我以前没有过多地使用 EJB。你能告诉我我错过了什么吗？

Answer 1

原因在这里：

nested exception is javax.naming.NameNotFoundException: Name [jndi/ejb/AssociateSessionEJB] is not bound in this Context. Unable to find [jndi].

为了解决这个问题，您需要指定正确的 JNDI 名称作为属性 jndiName 的值。您必须找出正确的名称，MyComponent EJB 在 JNDI 中可用。

另一件事是使用 EJB 的应用程序不能部署在 Tomcat 上，它是一个 servlet 容器。您需要使用例如TomEE 或其他 JEE 应用服务器。

Answer 2

如果您能够在兼容的容器中部署和运行“库”，那么可能的解决方案是使用特定库的远程接口（如果这些接口可用）从单独运行的 Spring 应用程序中使用。

Answer 3

正如您提供的文档中所解释的那样，我认为更简单的是将 ejb 类用作 POJO。

<beans:bean id="myComponent"
           class="com.company.serviceImpl.MyComponent"> 
</beans:bean>
<beans:bean id="loginService" class="com.company.serviceImpl.LoginServiceImpl">
            <beans:property name="myComponent" ref="myComponent"/>  
</beans:bean>