Could not create JarEntryRevision for......

错误：

Could not create JarEntryRevision for [jar:file:/D:/tools/apache-tomcat-6.0.32/webapps/ch02/WEB-INF/lib/struts2-core-2.2.3.jar]!
java.lang.NoClassDefFoundError: org/apache/commons/io/FileUtils......

?

?

可能是缺少commons-io-x.x.x.jar

?

?