SpringMVC 過濾非法字符

public class StringFilter extends  OncePerRequestFilter  {

    protected void doFilterInternal(HttpServletRequest request,
            HttpServletResponse response, FilterChain chain)
            throws ServletException, IOException {
        chain.doFilter(new StringFilterRequest((HttpServletRequest)request), response);
    }

    
        


}
class StringFilterRequest extends HttpServletRequestWrapper {
    public StringFilterRequest(HttpServletRequest request) {
        super(request);
    }

    @Override
    public String getParameter(String name) {
        // 返回值以前 先進行過濾
        return filterDangerString(super.getParameter(name));
    }

    @Override
    public String[] getParameterValues(String name) {
        // 返回值以前 先進行過濾
        String[] values = super.getParameterValues(name);
        if(values==null){
            return null;
        }
        for (int i = 0; i < values.length; i++) {
            values[i] = filterDangerString(values[i]);
        }

        return values;
    }

    @Override
    public Map getParameterMap() {
        Map keys = super.getParameterMap();
        Set set = keys.entrySet();
        Iterator iters = set.iterator();
        while (iters.hasNext()) {
            Object key = iters.next();
            Object value = keys.get(key);
            keys.put(key, filterDangerString((String[]) value));
        }
        return keys;
    }

    /*@Override
    public Object getAttribute(String name) {
        // TODO Auto-generated method stub
        Object object = super.getAttribute(name);
        if (object instanceof String) {
            return filterDangerString((String) super.getAttribute(name));
        } else
            return object;
    }*/

    public String filterDangerString(String value) {
        if (value == null) {
            return null;
        }
        value = value.replaceAll("\\{", "｛");
        // content = content.replaceAll("&", "&amp;");
        value = value.replaceAll("<", "&lt;");
        value = value.replaceAll(">", "&gt;");
        value = value.replaceAll("\t", "    ");
        value = value.replaceAll("\r\n", "\n");
        value = value.replaceAll("\n", "<br/>");
        value = value.replaceAll("'", "&#39;");
        value = value.replaceAll("\\\\", "&#92;");
        value = value.replaceAll("\"", "&quot;");
        value = value.replaceAll("\\}", "﹜").trim();
        return value;
    }
   
    public String[] filterDangerString(String[] value) {
        if (value == null) {
            return null;
        }
        for (int i = 0; i < value.length; i++) {
            String val = filterDangerString(value[i]);
            value[i] = val;
        }

        return value;
    }

}

使用ajax請求的時候返回一個Map對象到前端，出現特殊字符，能夠先轉義之後再傳。