Tomcat+MySql+Struts的中文有关问题 [过滤器]

Tomcat+MySql+Struts的中文问题 [过滤器]

开发Web应用程序时，无论是用什么样的框架技术来开发，一碰从数据库存取涉及到中文的数据，就要面对中文乱码或者是各种编码方式不匹配的异常，今天晚上终于搞定了Tomcat+MySql+Struts的中文问题，用到了很简单的方法，很快就能搞定。

在做以下工作之前，所有的HTML/JSP的charset都设为charset=gb2312。

第一个要解决的是表单提交乱码问题。在使用Struts提供的ActionForm过程中，无论表单采用的是Struts标签还是Html标签，都可以用ActionForm的Get/Set来获取和设置表单的元素值（它们的作用效果与request.getParameter()方法一样），但提取出来的数据不经过处理的话就是乱码，主要的原因是1.Tomcat的J2EE实现对表单提交即Post方法提交时，处理参数采用默认的ISO8859_1来处理2.Tomcat对Get方法提交的请求在query-string处理时采用了和Post方法不一样的处理方式。所以如果要正确地显示和获取中文数据采用的解决方案：（1）对于Post方法提交的表单通过编写一个过滤器（filer）的方法解决，过滤器在用户提交的数据被处理之前被调用，可以通过这个Java代码改变参数的编码方式（目标编码方式可以通过Web.xml文件里面的参数指定）。过滤器的代码如下：

import java.io.IOException;

import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;

import javax.servlet.UnavailableException;

/**

* Example filter that sets the character encoding to be used in parsing the

* incoming request, either unconditionally or only if the client did not

* specify a character encoding. Configuration of this filter is based on

* the following initialization parameters:

* <ul>

* <li>encoding – The character encoding to be configured

* for this request, either conditionally or unconditionally based on

* the <code>ignore</code> initialization parameter. This parameter

* is required, so there is no default.</li>

* <li>ignore – If set to “true”, any character encoding

* specified by the client is ignored, and the value returned by the

* <code>selectEncoding()</code> method is set. If set to “false,

* <code>selectEncoding()</code> is called only if the

* client has not already specified an encoding. By default, this

* parameter is set to “true”.</li>

* </ul>

*

* Although this filter can be used unchanged, it is also easy to

* subclass it and make the <code>selectEncoding()</code> method more

* intelligent about what encoding to choose, based on characteristics of

* the incoming request (such as the values of the <code>Accept-Language</code>

* and <code>User-Agent</code> headers, or a value stashed in the current

* user’s session.

*

* @author Craig McClanahan

* @version $Revision: 1.2 $ $Date: 2004/03/18 16:40:33 $

*/

public class SetCharacterEncodingFilter implements Filter {

// —————————————————– Instance Variables

    /**

     * The default character encoding to set for requests that pass through

     * this filter.

     */

    protected String encoding = null;

    /**

     * The filter configuration object we are associated with. If this value

     * is null, this filter instance is not currently configured.

     */

    protected FilterConfig filterConfig = null;

    /**

     * Should a character encoding specified by the client be ignored?

     */

&n

相关文章：

你感兴趣的文章：

标签云：