JSP中文乱码处理（过滤器）

SetEncodingFilter．java

 package cn.cmpy.publicinfo;

/**
* @author Administrator
*  过滤器，转码
*/
import javax.servlet.Filter;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.FilterChain;
import java.io.IOException;

public class SetEncodingFilter implements Filter {
 protected String encoding = null;
  /**
 * The filter configuration object we are associated with.  If this value
 * is null, this filter instance is not currently configured.
 */
  protected FilterConfig filterConfig = null;

  /**
 * Should a character encoding specified by the client be ignored?
 */
  protected boolean ignore = true;

  /**
 * Take this filter out of service.
 */
  public void destroy() {
  this.encoding = null;
  this.filterConfig = null;
  }

  /**
 * Select and set (if specified) the character encoding to be used to
 * interpret request parameters for this request.
 *
 * @param request The servlet request we are processing
 * @param result The servlet response we are creating
 * @param chain The filter chain we are processing
 *
 * @exception IOException if an input/output error occurs
 * @exception ServletException if a servlet error occurs
 */
  public void doFilter(
    ServletRequest request,
    ServletResponse response,
    FilterChain chain) throws IOException, ServletException {
  if(ignore || (request.getCharacterEncoding() == null)) {
            request.setCharacterEncoding(selectEncoding(request));
  }
  chain.doFilter(request, response);
  }

  /**
 * Place this filter into service.
 * @param filterConfig The filter configuration object
 */
  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") || value.equalsIgnoreCase("yes"))
    this.ignore = true;
  else
    this.ignore = false;
  }

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

  /**
 * Returns the filterConfig.
 * @return FilterConfig
 */
  public FilterConfig getFilterConfig() {
  return filterConfig;
  }

  /**
 * Sets the filterConfig.
 * @param filterConfig The filterConfig to set
 */
  public void setFilterConfig(FilterConfig filterConfig) {
  this.filterConfig = filterConfig;
  }

}
web.xml配置:

   <filter>
    <filter-name>EncodingFilter</filter-name>
    <filter-class>cn.cmpy.publicinfo.SetEncodingFilter</filter-class>
    <init-param>
      <param-name>encoding</param-name>
      <param-value>GBK</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>EncodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>