写了个过滤器怎么没用呢。还是出现乱码

Question

package filter;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 CharEncoding implements Filter { public void destroy() {
// TODO Auto-generated method stub } public void doFilter(ServletRequest arg0, ServletResponse arg1,
FilterChain arg2) throws IOException, ServletException {
arg0.setCharacterEncoding("GBK");
arg1.setCharacterEncoding("GBK");
arg2.doFilter(arg0, arg1);

} public void init(FilterConfig arg0) throws ServletException {
// TODO Auto-generated method stub }}

Answer 1

貌似没错，你在web.xml配置文件配置了没呢。
我觉得应该是那个问题

Answer 2

package creator.common.filter;import javax.servlet.http.*;public class CharacterEncodingHttpServletRequestWrapper extends HttpServletRequestWrapper {    private String ecoding = null;
    private String oldEncoding = null;    public CharacterEncodingHttpServletRequestWrapper(HttpServletRequest request,String encoding) {
        super(request);
        this.ecoding = encoding;
        this.oldEncoding = request.getCharacterEncoding();
    }    public String getParameter(String value) {
        try{
            if((oldEncoding == null || isIOS88591(oldEncoding)) && super.getParameter(value)!=null){
                return new String(super.getParameter(value).getBytes("iso-8859-1"),ecoding);
            }
            else{
                return super.getParameter(value);
            }
         }
        catch(Exception e){
            e.printStackTrace();
            return null;
        }
    }    private boolean isIOS88591(String endcoding){
        endcoding = endcoding.toLowerCase();
        return endcoding.startsWith("iso")&& (endcoding.indexOf("8859") != -1) && endcoding.endsWith("1");
    }
}
〔CharacterEncodingHttpServletResponseWrapper.java〕package creator.common.filter;import javax.servlet.http.*;public class CharacterEncodingHttpServletResponseWrapper extends HttpServletResponseWrapper {    private String ecoding = null;    public CharacterEncodingHttpServletResponseWrapper(HttpServletResponse response,String encoding) {
        super(response);
        this.ecoding = encoding;
    }    /* (non-Javadoc)
     * @see javax.servlet.ServletResponse#setContentType(java.lang.String)
     */
    public void setContentType(String value) {
        super.setContentType("text/html;charset="+ecoding);
    }}
〔CharsetEncodingFilter.java〕package creator.common.filter;import java.io.IOException;
import javax.servlet.*;
import javax.servlet.http.*;
public class CharsetEncodingFilter implements Filter {
    private FilterConfig config = null;
    private String RequestEncoding = null;
    private String ResponseEncoding = null;    public void init(FilterConfig arg0) throws ServletException {
        this.config = arg0;
        this.RequestEncoding = config.getInitParameter("RequestEncoding");
        this.ResponseEncoding = config.getInitParameter("ResponseEncoding");
    }    /* (non-Javadoc)
     * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest, javax.servlet.ServletResponse, javax.servlet.FilterChain)
     */
    public void doFilter(ServletRequest req, ServletResponse res, FilterChain fc)
        throws IOException, ServletException {
        if(this.config == null){
            return;
        }
        HttpServletRequest request = (HttpServletRequest)req;
        HttpServletResponse response = (HttpServletResponse)res;        CharacterEncodingHttpServletRequestWrapper  mrequestw  = new CharacterEncodingHttpServletRequestWrapper(request,ResponseEncoding);
        CharacterEncodingHttpServletResponseWrapper wresponsew = new CharacterEncodingHttpServletResponseWrapper(response,ResponseEncoding);
        fc.doFilter(mrequestw,wresponsew);
    }    public void destroy() {
    }}
〔web.xml〕  <filter>
    <filter-name>CharsetEncoding</filter-name>
    <filter-class>javabean.com.CharsetEncodingFilter</filter-class>
    <init-param>
      <param-name>RequestEncoding</param-name>
      <param-value>iso-8859-1</param-value>
    </init-param>
    <init-param>
      <param-name>ResponseEncoding</param-name>
      <param-value>gb2312</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>CharsetEncoding</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>