过滤器使用之全站乱码处理

public class EncodeFilter implements Filter {
    private String encode;
    public void init(FilterConfig config) throws ServletException {
        encode = config.getInitParameter("encode");
    }
    class MyHSR extends HttpServletRequestWrapper{
        private HttpServletRequest request;
        private boolean hasEncode = false;
        public MyHSR(HttpServletRequest request) {
            super(request);
            this.request = request;
        }
        @Override
        public Map<String,String[]> getParameterMap() {
            //获取提交的方式post/get
            if("POST".equals(request.getMethod())){
                try {
                    request.setCharacterEncoding(encode);
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                }
                return request.getParameterMap();
            }else if("GET".equals(request.getMethod())){
                //定义一个Map集合对象
                Map<String,String[]> map = request.getParameterMap();
                if(!hasEncode){
                    //遍历map
                    for(Map.Entry<String, String[]> entry:map.entrySet()){
                        //获取原来的vals
                        String[] vals = entry.getValue();
                        //遍历数组处理乱码
                        for (int i = 0;i<vals.length;i++) {
                            try {
                                vals[i] = new String(vals[i].getBytes("ISO8859-1"),encode);
                            } catch (UnsupportedEncodingException e) {
                                e.printStackTrace();
                            }
                        }
                    }
                    hasEncode = true;
                }
                return map;
            }else{//既不是get方式也不是post方式
                return super.getParameterMap();
            }
        }
        @Override
        public String[] getParameterValues(String name) {
            return getParameterMap().get(name);
        }
        @Override
        public String getParameter(String name) {
            return getParameterValues(name)==null?"":getParameterValues(name)[0];
        }
    }
    public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) throws IOException, ServletException {
        response.setContentType("text/html;charset=utf-8");
        chain.doFilter(new MyHSR((HttpServletRequest)request), response);

    }
    public void destroy() {
    }
}

 web.xml配置别忘了写啊！