抓住自己最有兴趣的东西，由浅入深，循序渐进地学……
<host id="www.xxx.com" root-directory=".">
<web-app id="/" root-directory="c:\WEB4javaApp">
<security-constraint>
<web-resource-collection>
<url-pattern>/*</url-pattern>
</web-resource-collection>
<ip-constraint>
<deny>116.211.0.xx</deny>
</ip-constraint>
</security-constraint>
</web-app>
</host>
