http://blog.csdn.net/joywy/article/details/8006645

ps1：最初的版本只有response.setContentType，後來被request.setCharacterEncoding替代了。

ps2：request只對post有效果。

ps3：request.setCharacterEncoding和response.setCharacterEncoding等同於spring的

<filter>
        <filter-name>encodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <async-supported>true</async-supported>
        

1. <init-param>
2.            <param-name>encoding</param-name>
3.            <param-value>UTF-8</param-value>
4.        </init-param>
5.        <init-param>
6.            <param-name>forceEncoding</param-name>
7.            <param-value>true</param-value>
8.        </
   init-param>

    </filter>

encoding只是設定了request的編碼格式，即在Servlet中：

        request.setCharacterEncoding("XXXX"); 

       如果設定forceEncoding的值為true時，相當於Servlet中：

       request.setCharacterEncoding("XXXX");

       response.setCharacterEncoding(“XXXX”); 

forceencoding預設值為false