例:
<servlet>
<servlet-name>welcome</servlet-name>
<servlet-class>WelcomeYou</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>welcome</servlet-name>
<url-pattern>/two</url-pattern>
</servlet-mapping>
<form action="two" method="get">
请输入用户名:<input type="text" name="user">
<input type="submit" value="提交">
</form>