解决跨应用服务器WEBLOGIC、TOMCAT编码问题

一、  描述
项目编码一向做为系统设计级别难题，servlet2.4还未实现跨应用服务器编码支持，个应用服务器之间编码存在很大差异，因此导致部署不同应用服务器上会出现不同乱码问题。为了实现开发环境(tomcat)和生产环境(weblogic9.2)编码统一，特此实现WEB.XML配置FILTER过滤编码，经过多次测试，基本实现跨应用服务器编码统一。
二、  配置（工程编码：UTF-8）
1．  个人编码规范
由于一些模块存在GET请求，在处理request.getParameter后出现乱码问题，一般个人实现方式为dwmc = new String(dwmc.getBytes("iso-8859-1"), "gb2312"); 此转码形式只适合一种应用服务器tomcat，为保证生产环境下weblogic能正常编码，需要：完全清理因个人书写而改变编码设置代码。并使用系统编码设置。
2．  系统配置TOMCAT
POST：系统web.xml中使用filter进行过滤POST请求，并其自动对其编码转换为utf-8。实现代码为 
request.setCharacterEncoding(encod);
GET：filter过滤无法为TOMCAT进行GET编码转换，因此需要修改TOMCAT/CONF/ server.xml文件，在项目Connector标签下增加URIEncoding="GB2312"属性。
3．  系统配置WEBLOGIC9.2
POST与GET统一处理方式，使用FILTER进行处理。判断request.getContentType()空的时候则为GET 请求，处理如下：
request.setCharacterEncoding(encod_wlc);
response.setContentType("application/x-www-form-urlencoded;charset="+ encod_wlc);
response.setCharacterEncoding(encod_wlc);
encod_wlc：为配置参数，此处：GB2312
POST请求则正常转换成utf-8即可，
request.setCharacterEncoding(encod);
三、  web.xml配置
    <filter>
        <filter-name>encodingFilter</filter-name>
        <filter-class>com.vstsoft.csi.util.SetCharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>//默认POST编码规则 
        </init-param>
        <init-param>
            <param-name>encoding_wlc</param-name>
            <param-value>GB2312</param-value>//默认WEBLOGIC下GET编码规则 
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>encodingFilter</filter-name>
        <url-pattern>*.do</url-pattern>
    </filter-mapping>
    <filter-mapping>
        <filter-name>encodingFilter</filter-name>
        <url-pattern>*.jsp</url-pattern>
</filter-mapping> 
四、  JAVA文件


package com.vstsoft.csi.util;

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;

public class SetCharacterEncodingFilter implements Filter {

    protected String encoding = null;

    protected String encoding_wlc = null;

    protected FilterConfig filterConfig = null;

    protected boolean ignore = true;

    public void destroy() {
        this.encoding = null;
        this.encoding_wlc=null;
        this.filterConfig = null;
    }

    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException {
        if (ignore || (request.getCharacterEncoding() == null)) {
            String encod = selectEncoding(request);
            String encod_wlc = selectEncoding_wlc(request);
            if (request.getContentType() == null) {
                request.setCharacterEncoding(encod_wlc);
                response.setContentType("application/x-www-form-urlencoded; charset="+ encod_wlc);
                response.setCharacterEncoding(encod_wlc);
            } else {
                request.setCharacterEncoding(encod);
            }
            encod=null;
            encod_wlc=null;
        }
        chain.doFilter(request, response);
    }

    public void init(FilterConfig filterConfig) throws ServletException {
        this.filterConfig = filterConfig;
        this.encoding = filterConfig.getInitParameter("encoding");
        this.encoding_wlc = filterConfig.getInitParameter("encoding_wlc");
        String value = filterConfig.getInitParameter("ignore");
        System.out.println("======>编码过滤初始化, 默认POST请求编码: "+this.encoding+", WBL下GET请求编码: "+this.encoding_wlc+"<=====");
        if (value == null)
            this.ignore = true;
        else if (value.equalsIgnoreCase("true"))
            this.ignore = true;
        else if (value.equalsIgnoreCase("yes"))
            this.ignore = true;
        else
            this.ignore = false;
    }

    protected String selectEncoding(ServletRequest request) {
        return (this.encoding);
    }
    
    protected String selectEncoding_wlc(ServletRequest request) {
        return (this.encoding_wlc);
    }
}