Web.xml错误解决方法

1.servlet书写顺序错误
现象：
       The content of element type "servlet" must match "(icon?,servlet-name,display-name?,description?,(servlet-class|jsp-file),init-param*,load-on-startup?,run-as?,security-role-ref*)".
原因：
       <!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd">
    要求Servlet的书写顺序必须是
        <servlet>
             <servlet-name>FilenameListServlet</servlet-name>
             <display-name>FilenameListServlet</display-name>
             <description>FilenameListServlet</description>
             <servlet-class>exam.FilenameListServlet</servlet-class>
       </servlet>
     而myeclipse自动生成的书写顺序是
        <servlet>
             <display-name>FilenameListServlet</display-name>
             <description>FilenameListServlet</description>
             <servlet-name>FilenameListServlet</servlet-name>
             <servlet-class>exam.FilenameListServlet</servlet-class>
       </servlet>
解决方法：
     按web-app_2_3.dtd要求的书写顺序即可。