编码过滤器

/** 编码过滤器 */
public class CharacterEncodingFilter implements Filter {

 String encoding = null;
 FilterConfig filterConfig = null;
 
 /** 初始化方法 */
 public void init(FilterConfig filterConfig) throws ServletException {
  this.filterConfig = filterConfig;
  this.encoding = filterConfig.getInitParameter("encoding");
 }

 /** 过滤处理方法 */
 public void doFilter(ServletRequest request, ServletResponse response,
   FilterChain chain) throws IOException, ServletException {
  if (encoding!=null){
   //对请求进行编码设置
   request.setCharacterEncoding(encoding);
  }
  //将处理权转交给下一个处理器
  chain.doFilter(request,response);
 }

 /** 销毁方法 */
 public void destroy() {
  this.encoding = null;
  this.filterConfig = null;