java.lang.NoClassDefFoundError: org/jaxen/JaxenException
dom4j解析XML时，导入了jaxen-1.1-beta-6.jar包和dom4j包。在调用
List<Element> data = server.selectNodes("Stat/Stat")时报如下错误，
其中server是一个Element;
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.sinodata.bsm.cicp.message.SyncMessageListener.onMessage(SyncMessageListener.java:110)
at org.apache.activemq.ActiveMQMessageConsumer.dispatch(ActiveMQMessageConsumer.java:1229)
at org.apache.activemq.ActiveMQSessionExecutor.dispatch(ActiveMQSessionExecutor.java:134)
at org.apache.activemq.ActiveMQSessionExecutor.iterate(ActiveMQSessionExecutor.java:205)
at org.apache.activemq.thread.PooledTaskRunner.runTask(PooledTaskRunner.java:122)
at org.apache.activemq.thread.PooledTaskRunner$1.run(PooledTaskRunner.java:43)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)
Caused by: java.lang.NoClassDefFoundError: org/jaxen/JaxenException
at org.dom4j.DocumentFactory.createXPath(DocumentFactory.java:230)
at org.dom4j.tree.AbstractNode.createXPath(AbstractNode.java:207)
at org.dom4j.tree.AbstractNode.selectNodes(AbstractNode.java:164)
at com.sinodata.bsm.cicp.finder.was6.WebAppFinder.find(WebAppFinder.java:81)
at com.sinodata.bsm.cicp.service.ResFindService.find(ResFindService.java:52)
... 13 more
Caused by: java.lang.ClassNotFoundException: org.jaxen.JaxenException
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
... 18 more

------解决方案--------------------
你的Jar文件没有在你的Class path里面所以导致JVM ClassLoader无法找到
并加载该Class