处理jsp中文乱码问题（过滤器处理）

其实写个过滤器是很方便的，可以起到“一招封喉”的作用，写了过滤器就不用在jsp的代码中，再考虑各种编码的问题了！请求和回应都会经过这个过滤器，转换成统一的编码格式。下面是过滤器的代码：

package com.suo;

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 CharacterEncodingFilter implements Filter
{
	protected String encoding=null;
	protected FilterConfig filterConfig=null;
	protected boolean ignore=true;
	
	public CharacterEncodingFilter(){}
	
	public void destroy()
	{
		this.encoding=null;
		this.filterConfig=null;
	}

	@Override
	public void doFilter(ServletRequest request, ServletResponse response,
			FilterChain chain) throws IOException, ServletException {
		// TODO Auto-generated method stub
		if(ignore || request.getCharacterEncoding()==null)
		{
			if(encoding!=null)
				request.setCharacterEncoding(encoding);
		}
		chain.doFilter(request, response);
	}

	@Override
	public void init(FilterConfig filterConfig) throws ServletException {
		// TODO Auto-generated method stub
		this.filterConfig=filterConfig;//从web.xml中取得参数。
		this.encoding=filterConfig.getInitParameter("encoding");
		String value=filterConfig.getInitParameter("ignore");
		if(value==null)
		{
			ignore=true;
		}
		else if(value.equalsIgnoreCase("true"))
		{
			ignore=true;
		}
		else if(value.equalsIgnoreCase("yes"))
		{
			ignore=true;
		}
		else
		{
			ignore=false;
		}
	}
	
}

然后在web.xml 中进行一下配置，关键是传递过去参数，即编码格式：

<filter>
  	<filter-name>CharacterEncoding</filter-name>
  	<filter-class>com.suo.CharacterEncodingFilter</filter-class>
  	<init-param>
  		<param-name>encoding</param-name>
  		<param-value>utf-8</param-value>
  	</init-param>
  </filter>
  <filter-mapping>
  	<filter-name>CharacterEncoding</filter-name>
  	<url-pattern>/*</url-pattern>
  </filter-mapping>