解决 STRUTS2 GET 参数中文乱码问题

STRUTS2中使用GET中文参数乱码问题,网上讨论这个问题的人很多却没有一个好的办法,于是唯有自己动脑了.

思路很简单,写一个filter放到filterchain最顶,将get参数值转为utf-8编码.

Filter:

package filter;

import java.io.IOException;
import java.util.Map;
import java.util.Set;

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.http.HttpServletRequest;




public class SetCharacterEncodingFilter implements Filter {


    // ----------------------------------------------------- Instance Variables


   
    protected String encoding = null;


   
    protected FilterConfig filterConfig = null;


   
    protected boolean ignore = true;


    // --------------------------------------------------------- Public Methods


   
    public void destroy() {

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

    }


   
    public void doFilter(ServletRequest request, ServletResponse response,
                         FilterChain chain)
 throws IOException, ServletException {

    	
    	//debug
    	//System.out.println("OH YEYEYE");
    	
        // Conditionally select and set the character encoding to be used
        if (ignore || (request.getCharacterEncoding() == null)) {
            String encoding = selectEncoding(request);
            if (encoding != null)
                request.setCharacterEncoding(encoding);
        }

        //process get parameters
        HttpServletRequest httpRequest = (HttpServletRequest)request;
        Map paramMap = request.getParameterMap();
        String[] queryStringArray = {""};
        if (httpRequest.getQueryString()!=null) {
        	queryStringArray = httpRequest.getQueryString().split("&");
		}
        for (int i = 0; i < queryStringArray.length; i++) {
        	queryStringArray[i] = queryStringArray[i].replaceAll("(.*)=(.*)", "$1");
		}
        Set<String> keySet = paramMap.keySet();
        for(String key : keySet){
        	//check where param from
        	boolean isFromGet = false;
        	for(String paramFromGet:queryStringArray){
        		if(key.equals(paramFromGet))
        		{
        			isFromGet = true;
        		}
        	}
        	if (!isFromGet) {
				continue;
			}
        	String[] paramArray = (String[])paramMap.get(key);
        	for(int i=0;i<paramArray.length;i++){
        			paramArray[i] = new String(paramArray[i].getBytes("iso-8859-1"),encoding);
        	}
        }
        
        
 // Pass control on to the next filter
        chain.doFilter(request, response);

    }


   
    public void init(FilterConfig filterConfig) throws ServletException {

 this.filterConfig = filterConfig;
        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 Methods


   
    protected String selectEncoding(ServletRequest request) {

        return (this.encoding);

    }

}

web.xml:

  <!-- encoding filter -->
	<filter>
		<filter-name>CharacterEncoding</filter-name>
		<filter-class>filter.SetCharacterEncodingFilter</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>

如果get和post中有参数同名结果可能不准确