org.springframework.beans.factory.CannotLoadBeanClassException:找不到类
问题内容:
我从tomcat 6.0安装目录中的servle-api.com替换了j2ee.jar:并产生以下错误。我目前正在尝试找出原因。可能是什么问题。
我在配置文件中定义了一个bean: Sempedia-service.xml,如下所示
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">
<bean id="sempediaSearchService"
class="com.service.SempediaSearchManager" />
</beans>
我的 web.xml 指定了以下bean:
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/Sempedia-service.xml,/WEB-INF/Sempedia-persistence.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
堆栈跟踪
SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.service.SempediaSearchManager] for bean with name 'sempediaSearchService' defined in ServletContext resource [/WEB-INF/Sempedia-service.xml]; nested exception is java.lang.ClassNotFoundException: com.service.SempediaSearchManager
at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1141)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:524)
at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1177)
at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:758)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:422)
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:3934)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4429)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:722)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
at org.apache.catalina.core.StandardService.start(StandardService.java:516)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
at org.apache.catalina.startup.Catalina.start(Catalina.java:583)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)
Caused by: java.lang.ClassNotFoundException: com.service.SempediaSearchManager
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1387)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1233)
at org.springframework.util.ClassUtils.forName(ClassUtils.java:211)
at org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:385)
at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1138)
... 24 more
问题答案:
问题在于com.service.SempediaSearchManager
您的Web应用程序的类路径中没有调用任何类。最可能的根本原因是:
-
完全合格的类名在中不正确
/WEB-INF/Sempedia-service.xml
;即类名是别的, -
该类不在Webapp的
/WEB-INF/classes
目录树中,也不在目录中的JAR文件中/WEB-INF/lib
。
编辑
:我能想到的唯一的另一件事是,这ClassDefNotFoundException
实际上可能是较早的类加载/静态初始化问题的结果。检查日志文件中的
第一个 堆栈跟踪,并查看嵌套异常,即“ caused”链。[如果类加载一次失败,并且您或Spring
Class.forName()
由于某种原因再次调用,那么Java实际上不会尝试第二次加载。相反,您将获得一个ClassDefNotFoundException
堆栈跟踪,该跟踪不能解释原始故障的真正原因。]
如果您仍然感到困惑,则应该将Eclipse排除在外。以最终将要部署的格式创建WAR文件,然后从命令行进行创建:
-
手动关闭Tomcat
-
清理您的Tomcat webapp目录,
-
将WAR文件复制到webapp目录中,
-
启动Tomcat。
如果那不能直接解决问题,请查看Tomcat上已部署的webapp目录,以确认“ missing”类在正确的位置。