java web编程中解决字符的另一招（RequestProcessor）

以前我都是用Filter （servlet）过滤器去 解决中文乱码（字符集）的问题 ，需要在web.xml配置2处。
但是今天 发现 RequestProcessor也可以解决字符集问题。 只需在web.xml种 配置一处 即可。
在此做个备忘！

java 代码

MyRequestProcessor.java
package StudyNews;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.RequestProcessor;

import org.apache.struts.config.ForwardConfig;
import org.apache.commons.logging.Log;


public class MyRequestProcessor extends RequestProcessor {

public MyRequestProcessor() {}

protected boolean processPreprocess( HttpServletRequest request,
                                     HttpServletResponse response ){

try{
   request.setCharacterEncoding("latin1");//此处为自己用的数据库的字符集 <4>

}
catch(Exception ex){
System.out.println("字符集设置失败");

}

return true;
}

}

xml

xml 代码

<controller processorClass="StudyNews.MyRequestProcessor" />

---------------------------------

java 代码

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   {

/*
  *   （非   Javadoc）
  *
  *   @see   javax.servlet.Filter#destroy()
  */
public   void   destroy()   {

this.encoding   =   null;
this.filterConfig   =   null;

}

public   void   doFilter(ServletRequest   request,   ServletResponse   response,
FilterChain   chain)   throws   IOException,   ServletException   {
//   选择使用的字符编码
if   (ignore   ¦ ¦   (request.getCharacterEncoding()   ==   null))   {
String   encoding   =   selectEncoding(request);
if   (encoding   !=   null)   {
request.setCharacterEncoding(encoding);

}
//   将控制权交给下一个Filter
chain.doFilter(request,   response);
}

}

// 将这个filter放置在服务中

java 代码

/*
  *   （非   Javadoc）
  *
  *   @see   javax.servlet.Filter#init(javax.servlet.FilterConfig)
  */
public   void   init(FilterConfig   filterConfig)   throws   ServletException   {
this.encoding   =   filterConfig.getInitParameter( "encoding ");
String   value   =   filterConfig.getInitParameter( "ignore ");
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   encoding   =   null;

protected   FilterConfig   filterConfig   =   null;

protected   boolean   ignore   =   true;

}

在web.xml文件中加入以下代码

xml 代码

xml 代码

<filter>  <filter-name> SetCharacterEncodingFilter </filter-name>  <filter-class> SetCharacterEncodingFilter </filter-class>  <init-param>  <param_name> encoding </param_name>  <param-value> GBK </param-value>  </init-param>  </filter>  <filter-mapping>  <filter-name> SetCharacterEncodingFilter </filter-name>  <url_pattern> /* </url_pattern>  </filter-mapping>