版本：spring3.1+hib4.1+struts2.1
学习项目使用此版本运行时，总是会遇到各样的错误，在这里做一下记录。
问题1：log4j相关
spring的web项目，执行时报错：
信息: Deploying web application archive SSH2.war
log4j:WARN No appenders could be found for logger (com.opensymphony.xwork2.config.providers.XmlConfigurationProvider).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
根据提示查看：
Why do I see a warning about "No appenders found for logger" and "Please configure log4j properly"?
This occurs when the default configuration files log4j.properties and log4j.xml can not be found and the application performs no explicit configuration. log4j uses Thread.getContextClassLoader().getResource() to locate the default configuration files and does not directly check the file system. Knowing the appropriate location to place log4j.properties or log4j.xml requires understanding the search strategy of the class loader in use. log4j does not provide a default configuration since output to the console or to the file system may be prohibited in some environments. Also see FAQ: Why can't log4j find my properties in a J2EE or WAR application?.
检查思路：
1.所需要的jar文件是否存在
2.log4j.properties有没有放到src目录下
3.web.xml中是否配置正确
1、检查log4j配置文件本身及路径，在web.xml中检查关于log4j的配置。
项目中指定加载spring的applicationContext.xml文件。
参考：WARN No appenders could be found for logger的解决方法
仔细查看web.xml发现在加载com.opensymphony.xwork2.config.providers.XmlConfigurationProvider这个listener之后才加载org.springframework.web.util.Log4jConfigListener，把log4j的配置放到org.springframework.web.context.ContextLoader之前。
<!-- 以下3项参数与log4j的配置相关 -->
<context-param>
<param-name>log4jConfigLocation</param-name>
<param-value>/WEB-INF/classes/log4j.properties</param-value>
</context-param>
<context-param>
<param-name>log4jRefreshInterval</param-name>
<param-value></param-value>
</context-param>
<listener>
<listener-class>
org.springframework.web.util.Log4jConfigListener
</listener-class>
</listener>
<!-- end --> <!-- 指定以 listener 方式启动spring -->
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
<!--指定spring 配置文件的配置 -->
<context-param>
<param-name>contextConfigLocation </param-name>
<param-value>/WEB-INF/classes/applicationContext.xml</param-value>
</context-param>
按此方式添加后，重新部署执行仍报错。
原来使用的是myecplise10.7，后直接导入到2013版本上直接运行出错，未再提示上述错误。
当启动myeclipse中的Tomcat时，首先他会自动查找工程中用到的自身文件夹下的common/lib下的jar文件，如果找到的话，就进行加载，然后才查找conf/下的log4j.properties等相关的配置文件，正是因为这样，才会报告没有初始化的信息。如果在common/lib下没有找到工程中要用到的jar文件，就先配置conf/下的配置文件，然后到工程中自身包含的lib下查找所用到的jar文件，这时就先把log4j的初始化工作作完了，所以这时在启动Tomcat时就不再提示没有初始化的警告信息了。
总结：在配置各种运行环境的时候，不要认为将要用到的jar文件拷贝到所有的相关的lib文件夹下，就会省很多事，想当然地认为用到时会自动调用，但是当相关配置有先后顺序的时候，会带来很多不必要的麻烦以及意想不到的问题。所以要充分地了解jar文件的用途以及他应该在的位置。
问题2：
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
解决方法：在web.xml中添加applicationContext.xml的调用即可
问题3：Exception sending context initialized event to listener instance
详细报错：
-- :: 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.BeanCreationException: Error creating bean with name 'sessionFactory' defined in ServletContext resource [/WEB-INF/classes/applicationContext.xml]: Invocation of init method failed; nested exception is org.hibernate.InvalidMappingException: Unable to read XML
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:)
at org.springframework.beans.factory.support.AbstractBeanFactory$.getObject(AbstractBeanFactory.java:)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:)
at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:)
at org.apache.catalina.core.StandardService.start(StandardService.java:)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:)
at org.apache.catalina.startup.Catalina.start(Catalina.java:)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:)
at java.lang.reflect.Method.invoke(Method.java:)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:)
Caused by: org.hibernate.InvalidMappingException: Unable to read XML
at org.hibernate.internal.util.xml.MappingReader.readMappingDocument(MappingReader.java:)
at org.hibernate.cfg.Configuration.add(Configuration.java:)
at org.hibernate.cfg.Configuration.add(Configuration.java:)
at org.hibernate.cfg.Configuration.add(Configuration.java:)
at org.hibernate.cfg.Configuration.addInputStream(Configuration.java:)
at org.springframework.orm.hibernate4.LocalSessionFactoryBean.afterPropertiesSet(LocalSessionFactoryBean.java:)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:)
... more
Caused by: org.dom4j.DocumentException: www.hibernate.org Nested exception: www.hibernate.org
at org.dom4j.io.SAXReader.read(SAXReader.java:)
at org.hibernate.internal.util.xml.MappingReader.readMappingDocument(MappingReader.java:)
... more
-- :: org.apache.catalina.core.StandardContext start
严重: Error listenerStart
-- :: org.apache.catalina.core.StandardContext start
严重: Context [/News] startup failed due to previous errors
查看hib相关的文件，生成实体类映射文件的头文件存在空格，如Topic.hbm.xml中“mapping-3.0.dtd ">”中dtd与“之间有空格，去掉此空格后，再次运行后就不再报此错了。
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd ">