JSP操作XML，删除节点问题
程序：
DocumentBuilderFactory   dbf   =   DocumentBuilderFactory.newInstance();
DocumentBuilder   db   =   dbf.newDocumentBuilder();

path   =   application.getRealPath( "/ ");

Document   doc   =   db.parse(path+ "left\\XML\\top.xml ");
NodeList   nl   =   doc.getElementsByTagName( "Tree ");  
nl.item(0).removeChild(doc.getElementById( "msdn "));


报错：
HTTP   Status   500   -  

--------------------------------------------

type   Exception   report

message  

description   The   server   encountered   an   internal   error   ()   that   prevented   it   from   fulfilling   this   request.

exception  

org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:373)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)


root   cause  

java.lang.NullPointerException
org.apache.xerces.dom.ParentNode.internalInsertBefore(ParentNode.java:339)
org.apache.xerces.dom.ParentNode.insertBefore(ParentNode.java:326)
org.apache.xerces.dom.NodeImpl.appendChild(NodeImpl.java:224)
org.apache.jsp.left.XML.deeptree_jsp._jspService(org.apache.jsp.left.XML.deeptree_jsp:99)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:99)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:325)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:291)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:241)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)


------解决方案--------------------
空指针错误,你得到的节点数据不存在吧?
------解决方案--------------------
空指针:你这句话能定位到top.xml上吗:Document doc = db.parse(path+ "left\\XML\\top.xml ");
看看path+ "left\\XML\\top.xml这个路径是不是你的top.xml的相对路径.
我的异常网推荐解决方案：The server encountered an internal error () that prevented it from fulfilling this request.,http://www.aiyiweb.com/java-web/317.html