org.dom4j.InvalidXPathException: Invalid XPath expression: '//head'. Caused by

org.dom4j.InvalidXPathException: Invalid XPath expression: '//head'. Caused by:
org.dom4j.InvalidXPathException: Invalid XPath expression: '//head'. Caused by: org/jaxen/dom4j/Dom4jXPath


主要是jaxen版本的问题，换成1.1.1就OK 不要使用FULL的版本