关于“Could not open ServletContext resource [/WEB-INF/applicationContext.xml]”解决方案

问题产生

最近学了Maven，并尝试将以前的项目（springmvc+myabtis）重构成Maven项目，Maven项目推荐各种资源文件都放在src/java/resources目录下，所以我自然把spring的配置文件（包括spring-mvc，spring-mybatis等配置都写在一个文件中）applicationContext.xml文件也放在了resources目录下，重构结束后，启动Tomcat报错：

八月 31, 2015 3:26:24 下午 org.apache.catalina.core.AprLifecycleListener init
信息: Loaded APR based Apache Tomcat Native library 1.1.22.
八月 31, 2015 3:26:24 下午 org.apache.catalina.core.AprLifecycleListener init
信息: APR capabilities: IPv6 [false], sendfile [true], accept filters [false], random [true].
八月 31, 2015 3:26:25 下午 org.apache.coyote.AbstractProtocol init
信息: Initializing ProtocolHandler ["http-apr-8080"]
八月 31, 2015 3:26:25 下午 org.apache.coyote.AbstractProtocol init
信息: Initializing ProtocolHandler ["ajp-apr-8009"]
八月 31, 2015 3:26:25 下午 org.apache.catalina.startup.Catalina load
信息: Initialization processed in 1784 ms
八月 31, 2015 3:26:25 下午 org.apache.catalina.core.StandardService startInternal
信息: Starting service Catalina
八月 31, 2015 3:26:25 下午 org.apache.catalina.core.StandardEngine startInternal
信息: Starting Servlet Engine: Apache Tomcat/7.0.26
八月 31, 2015 3:26:25 下午 org.apache.catalina.startup.HostConfig deployDirectory
信息: Deploying web application directory E:\java\apache-tomcat-7.0.26\webapps\host-manager
八月 31, 2015 3:26:26 下午 org.apache.catalina.startup.HostConfig deployDirectory
信息: Deploying web application directory E:\java\apache-tomcat-7.0.26\webapps\manager
八月 31, 2015 3:26:26 下午 org.apache.catalina.startup.HostConfig deployDirectory
信息: Deploying web application directory E:\java\apache-tomcat-7.0.26\webapps\ROOT
八月 31, 2015 3:26:26 下午 org.apache.catalina.startup.HostConfig deployDirectory
信息: Deploying web application directory E:\java\apache-tomcat-7.0.26\webapps\zhsz
八月 31, 2015 3:26:26 下午 org.apache.catalina.loader.WebappClassLoader validateJarFile
信息: validateJarFile(E:\java\apache-tomcat-7.0.26\webapps\zhsz\WEB-INF\lib\javaee.jar) - jar not loaded. See Servlet Spec 2.3, section 9.7.2. Offending class: javax/servlet/Servlet.class
八月 31, 2015 3:26:32 下午 org.apache.catalina.core.ApplicationContext log
信息: No Spring WebApplicationInitializer types detected on classpath
log4j:ERROR Could not find value for key log4j.appender.stdout
log4j:ERROR Could not instantiate appender named "stdout".
log4j:ERROR Could not find value for key log4j.appender.debug
log4j:ERROR Could not instantiate appender named "debug".
八月 31, 2015 3:26:32 下午 org.apache.catalina.core.ApplicationContext log
信息: Initializing Spring root WebApplicationContext
八月 31, 2015 3:26:33 下午 org.apache.catalina.core.StandardContext listenerStart
严重: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanDefinitionStoreException: IOException parsing XML document from ServletContext resource [/WEB-INF/applicationContext.xml]; nested exception is java.io.FileNotFoundException: Could not open ServletContext resource [/WEB-INF/applicationContext.xml]
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:341)
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:302)
	at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:174)
	at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:209)
	at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:180)
	at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:125)
	at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:94)
	at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:131)
	at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:522)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:436)
	at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:385)
	at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:284)
	at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:111)
	at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4779)
	at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5273)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:895)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:871)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:615)
	at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1095)
	at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1617)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
	at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
	at java.util.concurrent.FutureTask.run(FutureTask.java:166)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
	at java.lang.Thread.run(Thread.java:722)
Caused by: java.io.FileNotFoundException: Could not open ServletContext resource [/WEB-INF/applicationContext.xml]
	at org.springframework.web.context.support.ServletContextResource.getInputStream(ServletContextResource.java:140)
	at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:328)
	... 26 more
八月 31, 2015 3:26:33 下午 org.apache.catalina.core.StandardContext startInternal
严重: Error listenerStart
八月 31, 2015 3:26:33 下午 org.apache.catalina.core.StandardContext startInternal
严重: Context [/zhsz] startup failed due to previous errors
八月 31, 2015 3:26:33 下午 org.apache.catalina.core.ApplicationContext log
信息: Closing Spring root WebApplicationContext
八月 31, 2015 3:26:33 下午 org.apache.catalina.core.StandardContext listenerStop
严重: Exception sending context destroyed event to listener instance of class org.springframework.web.context.ContextLoaderListener
java.lang.IllegalStateException: BeanFactory not initialized or already closed - call 'refresh' before accessing beans via the ApplicationContext
	at org.springframework.context.support.AbstractRefreshableApplicationContext.getBeanFactory(AbstractRefreshableApplicationContext.java:172)
	at org.springframework.context.support.AbstractApplicationContext.destroyBeans(AbstractApplicationContext.java:1066)
	at org.springframework.context.support.AbstractApplicationContext.doClose(AbstractApplicationContext.java:1040)
	at org.springframework.context.support.AbstractApplicationContext.close(AbstractApplicationContext.java:988)
	at org.springframework.web.context.ContextLoader.closeWebApplicationContext(ContextLoader.java:556)
	at org.springframework.web.context.ContextLoaderListener.contextDestroyed(ContextLoaderListener.java:142)
	at org.apache.catalina.core.StandardContext.listenerStop(StandardContext.java:4819)
	at org.apache.catalina.core.StandardContext.stopInternal(StandardContext.java:5466)
	at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:232)
	at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:160)
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:895)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:871)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:615)
	at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1095)
	at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1617)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
	at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
	at java.util.concurrent.FutureTask.run(FutureTask.java:166)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
	at java.lang.Thread.run(Thread.java:722)
八月 31, 2015 3:26:33 下午 org.apache.coyote.AbstractProtocol start
信息: Starting ProtocolHandler ["http-apr-8080"]
八月 31, 2015 3:26:33 下午 org.apache.coyote.AbstractProtocol start
信息: Starting ProtocolHandler ["ajp-apr-8009"]
八月 31, 2015 3:26:33 下午 org.apache.catalina.startup.Catalina start
信息: Server startup in 7589 ms

注意一下，其实重点就一句话，即Could not open ServletContext resource [/WEB-INF/applicationContext.xml]，异常也很明显，FileNotException，无法打开ServletContext的资源文件。下面再看一下web.xml的配置：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns="http://java.sun.com/xml/ns/javaee"
	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
	http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
	id="WebApp_ID" version="3.0">
	<display-name>xxybm</display-name>

	<listener>
		<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
	</listener>

	<servlet>
		<servlet-name>springMvc</servlet-name>
		<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
		<init-param>
			<param-name>contextConfigLocation</param-name>
			<param-value>classpath:applicationContext.xml</param-value>
		</init-param>
		<load-on-startup>2</load-on-startup>
	</servlet>

	<servlet-mapping>
		<servlet-name>springMvc</servlet-name>
		<url-pattern>/app/*</url-pattern>
	</servlet-mapping>


	<filter>
		<filter-name>SecurityFilter</filter-name>
		<filter-class>net.zhsz.util.LoginCheckFilter</filter-class>
	</filter>
	<filter-mapping>
		<filter-name>SecurityFilter</filter-name>
		<url-pattern>*.jsp</url-pattern>
	</filter-mapping>
	<filter-mapping>
		<filter-name>SecurityFilter</filter-name>
		<url-pattern>/app/*</url-pattern>
	</filter-mapping>


	<session-config>
		<session-timeout>30</session-timeout>
	</session-config>


	<error-page>
		<exception-type>java.lang.Exception</exception-type>
		<location>/500.html</location>
	</error-page>

</web-app>

由于在没用Maven之前，我的spring配置文件——applicationContext.xml是放在WEB-INF根目录下的，在项目运行时都是正常的，重构成Maven项目之后，我的配置文件自然应该放在src下的resources文件夹下了，那么在web.xml中我自然将<init-param>中contextConfigLocation的参数值由WEB-INF/applicationContext.xml修改为classpath:applicationContext.xml了，那么启动tomcat之后依然报错，而且我们从报错信息中可以看出容器依然是在WEB-INF下去找applicationContext.xml，很明显这个文件的位置已经被我们改变了，而且我们也修改了web.xml的配置为何还要从这里去加载呢？原因是我们缺少另一个重要的配置。

解决问题

遇到问题盲目搜索往往不能迅速得到有效的解决方案，所以我们先从官方去寻找线索，看一看spring的官方文档，在The Web的章节中可以发现这样一段话：

简单翻译一下上图标记的小段落：如果不特意指定参数名为contextConfigLoction的<context-parameter>元素，那么spring的ContextLoderListener监听器就会在/WEB-INF/下去寻找并加载该目录下的名为applicationContext.xml这个文件。So，我们应该在web.xml中添加<context-param>标签并再次指定spring核心文件的位置：

<context-param>
	<param-name>contextConfigLocation</param-name>
	<param-value>classpath:applicationContext.xml</param-value>
</context-param>

这样就OK了，注意这段配置尽量写在靠前的位置，因为在tomcat启动后web项目会先初始化上下文，我们这段配置正是指定了上下文配置的文件位置，在上下文初始化完成之后才应当继续加载其余各种配置，而我们的springMVC的servlet仅仅是springMVC框架的相关配置，就好比struts2的配置一样，项目整体还是由spring去管理的。下面是修改之后的web.xml配置文件：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns="http://java.sun.com/xml/ns/javaee"
	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
	http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
	id="WebApp_ID" version="3.0">
	<display-name>xxybm</display-name>
	
	<context-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>classpath:applicationContext.xml</param-value>
	</context-param>

	<listener>
		<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
	</listener>

	<servlet>
		<servlet-name>springMvc</servlet-name>
		<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
		<init-param>
			<param-name>contextConfigLocation</param-name>
			<param-value>classpath:applicationContext.xml</param-value>
		</init-param>
		<load-on-startup>2</load-on-startup>
	</servlet>

	<servlet-mapping>
		<servlet-name>springMvc</servlet-name>
		<url-pattern>/app/*</url-pattern>
	</servlet-mapping>

	<filter>
		<filter-name>SecurityFilter</filter-name>
		<filter-class>net.zhsz.util.LoginCheckFilter</filter-class>
	</filter>
	
	<filter-mapping>
		<filter-name>SecurityFilter</filter-name>
		<url-pattern>*.jsp</url-pattern>
	</filter-mapping>
	
	<filter-mapping>
		<filter-name>SecurityFilter</filter-name>
		<url-pattern>/app/*</url-pattern>
	</filter-mapping>

	<session-config>
		<session-timeout>30</session-timeout>
	</session-config>

	<error-page>
		<exception-type>java.lang.Exception</exception-type>
		<location>/500.html</location>
	</error-page>
</web-app>

最后再次启动项目，运行正常，spring和springMVC均正常加载并初始化。之前在网上查的有人说修改路径，加星号，又是少jar包，答案千奇百怪，然后都无法解决问题，总之这篇blog希望能对遇到这个异常的朋友有所帮助，The End。