步驟一，tomcat的conf目錄下tomcat-users.xml內容如下：
<?xml version='1.0' encoding='utf-8'?>

<tomcat-users>

  <role rolename="manager"/>

  <role rolename="admin"/>

  <user username="xiaolu" password="xiaolu" roles="admin,manager"/>

</tomcat-users>
步驟二，在web.xml中增加如下內容：
<

       <web-resource-collection>

           <web-resource-name>xiaolu</web-resource-name>

           <url-pattern>/xiaolu/*</

           <http-method>POST</http-method>

           <http-method>GET</http-method>

       </web-resource-collection>

       <

           <role-name>admin</role-name>

       </auth-constraint>

    </security-constraint>

    <security-role>

       <role-name>admin</role-name>

    </security-role>

    <login-config>

       <auth-method>BASIC</auth-method>

       <realm-name>input authentication message</realm-name>

    </login-config>