DWR学习中遇到的问题请高人帮助

java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory
at org.directwebremoting.dwrp.PollHandler.<clinit>(PollHandler.java:443)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.directwebremoting.impl.ContainerUtil.class$(ContainerUtil.java:97)
at org.directwebremoting.impl.ContainerUtil.setupDefaults(ContainerUtil.java:150)
at org.directwebremoting.impl.ContainerUtil.setupDefaultContainer(ContainerUtil.java:125)
at org.directwebremoting.servlet.DwrServlet.init(DwrServlet.java:73)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1161)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:806)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:133)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445)
at java.lang.Thread.run(Unknown Source)
2008-10-28 9:24:46 org.apache.catalina.core.StandardWrapperValve invoke
严重: Allocate exception for servlet dwr
java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory
at org.directwebremoting.dwrp.PollHandler.<clinit>(PollHandler.java:443)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.directwebremoting.impl.ContainerUtil.class$(ContainerUtil.java:97)
at org.directwebremoting.impl.ContainerUtil.setupDefaults(ContainerUtil.java:150)
at org.directwebremoting.impl.ContainerUtil.setupDefaultContainer(ContainerUtil.java:125)
at org.directwebremoting.servlet.DwrServlet.init(DwrServlet.java:73)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1161)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:806)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:133)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445)
at java.lang.Thread.run(Unknown Source)
2008-10-28 9:24:46 org.apache.catalina.core.ApplicationContext log
严重: StandardWrapper.Throwable
java.lang.NoClassDefFoundError: Could not initialize class org.directwebremoting.servlet.PlainPollHandler
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.directwebremoting.impl.ContainerUtil.class$(ContainerUtil.java:97)
at org.directwebremoting.impl.ContainerUtil.setupDefaults(ContainerUtil.java:150)
at org.directwebremoting.impl.ContainerUtil.setupDefaultContainer(ContainerUtil.java:125)
at org.directwebremoting.servlet.DwrServlet.init(DwrServlet.java:73)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1161)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:806)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:133)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445)
at java.lang.Thread.run(Unknown Source)
2008-10-28 9:24:46 org.apache.catalina.core.StandardWrapperValve invoke
严重: Allocate exception for servlet dwr
java.lang.NoClassDefFoundError: Could not initialize class org.directwebremoting.servlet.PlainPollHandler
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.directwebremoting.impl.ContainerUtil.class$(ContainerUtil.java:97)
at org.directwebremoting.impl.ContainerUtil.setupDefaults(ContainerUtil.java:150)
at org.directwebremoting.impl.ContainerUtil.setupDefaultContainer(ContainerUtil.java:125)
at org.directwebremoting.servlet.DwrServlet.init(DwrServlet.java:73)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1161)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:806)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:133)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445)
at java.lang.Thread.run(Unknown Source)
2008-10-28 9:24:46 org.apache.catalina.core.ApplicationContext log
严重: StandardWrapper.Throwable
java.lang.NoClassDefFoundError: Could not initialize class org.directwebremoting.servlet.PlainPollHandler
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.directwebremoting.impl.ContainerUtil.class$(ContainerUtil.java:97)
at org.directwebremoting.impl.ContainerUtil.setupDefaults(ContainerUtil.java:150)
at org.directwebremoting.impl.ContainerUtil.setupDefaultContainer(ContainerUtil.java:125)
at org.directwebremoting.servlet.DwrServlet.init(DwrServlet.java:73)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1161)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:806)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:133)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445)
at java.lang.Thread.run(Unknown Source)
2008-10-28 9:24:46 org.apache.catalina.core.StandardWrapperValve invoke
严重: Allocate exception for servlet dwr
java.lang.NoClassDefFoundError: Could not initialize class org.directwebremoting.servlet.PlainPollHandler
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.directwebremoting.impl.ContainerUtil.class$(ContainerUtil.java:97)
at org.directwebremoting.impl.ContainerUtil.setupDefaults(ContainerUtil.java:150)
at org.directwebremoting.impl.ContainerUtil.setupDefaultContainer(ContainerUtil.java:125)
at org.directwebremoting.servlet.DwrServlet.init(DwrServlet.java:73)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1161)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:806)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:133)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:216)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:634)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:445)
at java.lang.Thread.run(Unknown Source)

 

问题补充：
zhjb2000 commons-logging.jar 缺了这个包



在看DWR文档的时候 并没有说要引入这个包啊
问题补充：
zhjb2000 谢谢你的回答 但是你的回答还不能解决我的疑问。如果实在没有更好答案就给分给你了
问题补充：
疑问。。我第一次写DWR程序的时候是直接再我以前写的Struts项目下面写的DWR程序。当时并没有报缺少commons-logging.jar 错误（因为有这个包）。后来自己建了个工程写了个最简单的例子。就报了 我上面发的错误。实在不解，于是我导入了Struts jar包（包含commons-logging.jar ），新写的例子就可以用了。最后我又删除了Struts jar包（commons-logging.jar 也删除了）工程照样可以运行。。

commons-logging.jar 缺了这个包

java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory 报错很明显了，找不到这个类，而这个类是在commons-logging.jar 这个包里面，安装文档有没有写我就不太清楚了

你的疑问是什么？为什么会报错？报错是因为缺少了jar，I还是其他的问题？

其实呢我自思根据你提供的报错信息进行分析，报错显示，找不到org/apache/commons/logging/LogFactory 这个类，我就查了一下，这个嘎类一般应该在commons-logging.jar这个包下面，所以给出你答案，也有可能在其他包里面有有这个类，所以你把commons-logging.jar删除也不会报错

缺了commons-logging.jar，用于打印日志的。一般的程序都配置了，所以没有特别说明吧