java.lang.NoClassDefFoundError:
严重:   Servlet.service()   for   servlet   BackGroundService   threw   exception
java.lang.NoClassDefFoundError:   org/apache/commons/io/output/DeferredFileOutputStream
at   org.apache.commons.fileupload.disk.DiskFileItemFactory.createItem(DiskFileItemFactory.java:191)
at   org.apache.commons.fileupload.FileUploadBase.parseRequest(FileUploadBase.java:350)
at   org.apache.commons.fileupload.servlet.ServletFileUpload.parseRequest(ServletFileUpload.java:126)
at   liuzuochen.sample.upload.BackGroundService.processFileUpload(BackGroundService.java:130)
at   liuzuochen.sample.upload.BackGroundService.doPost(BackGroundService.java:202)
at   javax.servlet.http.HttpServlet.service(HttpServlet.java:709)
at   javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at   org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:252)
at   org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:173)
at   org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:213)
at   org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:178)
at   org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:126)
at   org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:105)
at   org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:107)
at   org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:148)
at   org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:869)
at   org.apache.coyote.http11.Http11BaseProtocol$Http11ConnectionHandler.processConnection(Http11BaseProtocol.java:664)
at   org.apache.tomcat.util.net.PoolTcpEndpoint.processSocket(PoolTcpEndpoint.java:527)
at   org.apache.tomcat.util.net.LeaderFollowerWorkerThread.runIt(LeaderFollowerWorkerThread.java:80)
at   org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:684)
at   java.lang.Thread.run(Thread.java:619)
请高手帮忙!!!!!


------解决方案--------------------
没定义类？
------解决方案--------------------
apache的IO包没有 需要在你工程的lib下放common-io.jar
------解决方案--------------------
commons-io.jar没有找到，检查一下lib是否完整，正确