Spring Boot中Configuration problem: Cannot locate BeanDefinitionParser for element 的问题分析

环境信息

Spring Boot 2.0.2 JDK 8, OS: windows 7

问题的提出

今天在开发中，碰到一下类似的错误信息：

15:44:09.198 INFO  com.jd.ai.cv.api.PubAPIApplication.logStarting@50 - Starting PubAPIApplication on ZB-PF0V10MN with PID 4324 (D:\CodeSpace\photobuyapi\target\classes started by chenjunfeng1 in D:\CodeSpace\photobuyapi)
15:44:09.203 DEBUG com.jd.ai.cv.api.PubAPIApplication.logStarting@53 - Running with Spring Boot v2.0.2.RELEASE, Spring v5.0.6.RELEASE
15:44:09.204 INFO  com.jd.ai.cv.api.PubAPIApplication.logStartupProfileInfo@659 - No active profile set, falling back to default profiles: default
15:44:09.252 INFO  org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext.prepareRefresh@590 - Refreshing org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext@6422b7d4: startup date [Fri May 18 15:44:09 CST 2018]; root of context hierarchy
15:44:09.708 INFO  org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions@316 - Loading XML bean definitions from class path resource [spring-config-jmq.xml]
15:44:09.776 WARN  org.springframework.boot.web.servlet.context.AnnotationConfigServletWebServerApplicationContext.refresh@558 - Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Cannot locate BeanDefinitionParser for element [listener]
Offending resource: class path resource [spring-config-jmq.xml]
15:44:09.781 INFO  org.springframework.boot.autoconfigure.logging.ConditionEvaluationReportLoggingListener.logAutoConfigurationReport@101 - Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
15:44:09.787 ERROR org.springframework.boot.SpringApplication.reportFailure@842 - Application run failed
org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Cannot locate BeanDefinitionParser for element [listener]
Offending resource: class path resource [spring-config-jmq.xml]at org.springframework.beans.factory.parsing.FailFastProblemReporter.fatal(FailFastProblemReporter.java:62) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.parsing.ReaderContext.fatal(ReaderContext.java:90) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.parsing.ReaderContext.fatal(ReaderContext.java:68) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.NamespaceHandlerSupport.findParserForElement(NamespaceHandlerSupport.java:86) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.NamespaceHandlerSupport.parse(NamespaceHandlerSupport.java:73) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1366) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1352) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:178) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.doRegisterBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:148) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.registerBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:98) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.registerBeanDefinitions(XmlBeanDefinitionReader.java:507) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:391) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:335) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:303) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:187) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:223) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:194) ~[spring-beans-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.lambda$loadBeanDefinitionsFromImportedResources$0(ConfigurationClassBeanDefinitionReader.java:352) ~[spring-context-5.0.6.RELEASE.jar:5.0.6.RELEASE]at java.util.LinkedHashMap.forEach(LinkedHashMap.java:684) ~[?:1.8.0_144]at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsFromImportedResources(ConfigurationClassBeanDefinitionReader.java:319) ~[spring-context-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitionsForConfigurationClass(ConfigurationClassBeanDefinitionReader.java:144) ~[spring-context-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.context.annotation.ConfigurationClassBeanDefinitionReader.loadBeanDefinitions(ConfigurationClassBeanDefinitionReader.java:117) ~[spring-context-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:328) ~[spring-context-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:233) ~[spring-context-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:273) ~[spring-context-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:93) ~[spring-context-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:694) ~[spring-context-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:532) ~[spring-context-5.0.6.RELEASE.jar:5.0.6.RELEASE]at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.2.RELEASE.jar:2.0.2.RELEASE]at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) [spring-boot-2.0.2.RELEASE.jar:2.0.2.RELEASE]at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:395) [spring-boot-2.0.2.RELEASE.jar:2.0.2.RELEASE]at org.springframework.boot.SpringApplication.run(SpringApplication.java:327) [spring-boot-2.0.2.RELEASE.jar:2.0.2.RELEASE]at org.springframework.boot.SpringApplication.run(SpringApplication.java:1255) [spring-boot-2.0.2.RELEASE.jar:2.0.2.RELEASE]at org.springframework.boot.SpringApplication.run(SpringApplication.java:1243) [spring-boot-2.0.2.RELEASE.jar:2.0.2.RELEASE]at com.jd.ai.cv.api.PubAPIApplication.main(PubAPIApplication.java:16) [classes/:?]at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_144]at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_144]at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_144]at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_144]at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-2.0.2.RELEASE.jar:2.0.2.RELEASE]

好奇怪的问题呀……

问题的分析

其中的关键信息是：
org.springframework.beans.factory.parsing.BeanDefinitionParsingException: Configuration problem: Cannot locate BeanDefinitionParser for element [listener] Offending resource: class path resource [spring-config-jmq.xml]
从上述错误信息分析，可知问题在spring-config-jmq.xml文件中，这个是非常明显的。错误的问题是在解析Bean的时候出现的BeanDefinitionParsingException，原因是Confgiuration错误，元素错误，其中的一个元素是listener。
结合这个错误信息可知，listener这个节点在与某个Bean的解析中，发生了问题，至于是什么问题，需要结合配置文件来分析。
查看之后发现：
<jmq:listener topic="aifashion_producer" listener="consumertest" /> ....................... <jmq:consumer id="consumer" transport="jmq.transport" longPull="10000" pullTimeout="11000" autoStart="true"> <jmq:listener topic="@sys.jmq.product.topic.price@" listener="productPriceListener" maxConcurrent="10" minConcurrent="1" /> </jmq:consumer>
在上述配置中，可以发现listener节点竟然没有放在jmq:consumer节点中，所以导致了此问题的发生。真是汗颜呀，纯粹声明的时候晕了头……

总结

低级错误一个，但是基于异常信息来分析得出问题的大致根源和方向是最有价值的一件事情。