Question

如果我在ServiceBean中使用它（不好的做法，但它应该可以工作）

package xxx;

import javax.servlet.http.HttpServletRequest;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class LanguageService {
  @Autowired(required=false)
  HttpServletRequest request;
}

该字段不是必需的，但是tomcat的开始时会抛出BeanCreationException（在任何请求之前！）：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'languageService': Autowiring of fields failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: javax.servlet.ServletRequest xxx.LanguageService.request; nested exception is java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet/DispatcherPortlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessAfterInstantiation(AutowiredAnnotationBeanPostProcessor.java:243)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:959)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:472)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory$1.run(AbstractAutowireCapableBeanFactory.java:409)
    at java.security.AccessController.doPrivileged(Native Method)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:380)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:264)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:261)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:185)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:164)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:429)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:728)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:380)
    at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:255)
    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:199)
    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:45)
    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4939)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)
    at java.util.concurrent.FutureTask.run(FutureTask.java:262)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:744)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: javax.servlet.ServletRequest xxx.LanguageService.request; nested exception is java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet/DispatcherPortlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:435)
    at org.springframework.beans.factory.annotation.InjectionMetadata.injectFields(InjectionMetadata.java:105)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessAfterInstantiation(AutowiredAnnotationBeanPostProcessor.java:240)
    ... 25 more
Caused by: java.lang.IllegalStateException: No thread-bound request found: Are you referring to request attributes outside of an actual web request, or processing a request outside of the originally receiving thread? If you are actually operating within a web request and still receive this message, your code is probably running outside of DispatcherServlet/DispatcherPortlet: In this case, use RequestContextListener or RequestContextFilter to expose the current request.
    at org.springframework.web.context.request.RequestContextHolder.currentRequestAttributes(RequestContextHolder.java:122)
    at org.springframework.web.context.support.WebApplicationContextUtils$1.getObject(WebApplicationContextUtils.java:131)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:660)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:610)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:412)
    ... 27 more

我是否只需要在session-component-bean中连接它？

Answer 1

我们还没有看到你的上下文以及它们是如何加载的，但我认为你的问题是你在ContextLoaderListener加载的上下文中初始化你的服务bean（给你的堆栈跟踪）而不是由DispatcherServlet加载的那个。切换它，它应该工作。

Autowire ServletRequest不是必需的，但抛出BeanCreationException

1 个答案: