struts2更新版本操作有关事项备注，
更新主要jar包：struts2-convention-plugin-version，struts2-core-version, struts2-spring-plugin-version
依赖jar包:xwork-core-version
报错应更新有关jar包: freemarker-verson，log4j-version
mevan实例：
<!-- struts2 所有jar包 -->
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-core</artifactId>
<!--<version>2.2.1</version>-->
<version>2.3.24.1</version>
<exclusions>
<exclusion>
<groupId>com.sun</groupId>
<artifactId>tools</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-spring-plugin</artifactId>
<!--<version>2.2.1</version>-->
<version>2.3.24.1</version>
</dependency>
<dependency>
<groupId>org.apache.struts</groupId>
<artifactId>struts2-convention-plugin</artifactId>
<!--<version>2.2.1</version>-->
<version>2.3.24.1</version>
</dependency>
<dependency>
<groupId>org.freemarker</groupId>
<artifactId>freemarker</artifactId>
<version>2.3.23</version>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
xwork-core-version此包不更新涉及报错：
<filter>
<filter-name>StrutsPrepareFilter</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareFilter</filter-class>
</filter>
<filter>
<filter-name>StrutsExecuteFilter</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsExecuteFilter</filter-class>
</filter>
此配置文件 类丢失错误
freemarker-verson，log4j-version 包不更新涉及报错：
java.lang.NoSuchFieldError: VERSION_2_3_0
at org.apache.struts2.views.freemarker.FreemarkerManager.createConfiguration(FreemarkerManager.java:331)
at org.apache.struts2.views.freemarker.FreemarkerManager.init(FreemarkerManager.java:282)
at org.apache.struts2.views.freemarker.FreemarkerManager.getConfiguration(FreemarkerManager.java:269)
at org.apache.struts2.dispatcher.DefaultDispatcherErrorHandler.init(DefaultDispatcherErrorHandler.java:47)
at org.apache.struts2.dispatcher.Dispatcher.init(Dispatcher.java:488)
at org.apache.struts2.dispatcher.ng.InitOperations.initDispatcher(InitOperations.java:74)
at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.init(StrutsPrepareAndExecuteFilter.java:57)
at org.apache.catalina.core.ApplicationFilterConfig.initFilter(ApplicationFilterConfig.java:281)
at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:262)
at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:107)
at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4746)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5399)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1114)
at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1672)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)