web.xml 大红叉
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/j2ee" 
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_5.xsd"
 version="2.5">
 <servlet>
        <servlet-name>MaServlet</servlet-name>
        <servlet-class>Lin.MyServlet</servlet-class>
</servlet>
    
<servlet-mapping>
        <servlet-name>MaServlet</servlet-name>
        <url-pattern>/MyServlet</url-pattern>
</servlet-mapping>
</web-app>
一些马上就是大红叉，怎么解决？
------解决方案--------------------
http://java.sun.com/xml/ns/j2ee
改成
http://java.sun.com/xml/ns/javaee
两处