public String getRequestSign(Map<String, String> map) {
        ArrayList<Map.Entry<String, String>> list = new ArrayList<Map.Entry<String, String>>(map.entrySet());
        Collections.sort(list, new Comparator<Map.Entry<String, String>>() {
            @Override
            public int compare(Map.Entry<String, String> lhs, Map.Entry<String, String> rhs) {
                return lhs.getKey().compareTo(rhs.getKey());
            }
        });
        StringBuilder builder = new StringBuilder();
        for (int i = 0; i < list.size(); i = i + 1) {
            Map.Entry<String, String> map1 = list.get(i);
            builder.append(map1.getKey()).append(map1.getValue());
        }
        builder.append("3542e676b4c80983f6131cdfe577ac9b");
        logger.debug("builder:" + builder.toString());
        return securityHelper.getMD5(builder.toString());
    }

public void getGroupThreadsList(String groupId, String lastId, String type, List<String> list, Callback<ThreadsResult> callback) {
        Map<String, String> params = requestHelper.getHttpRequestMap();
        params.put("groupId", groupId);
        params.put("lastId", lastId);
        params.put("limit", "20");
        if (list == null) {
            params.put("special", "0");
            params.put("type", type);
        } else {
            JSONArray jSONArray = new JSONArray();
            for (String str : list) {
                jSONArray.put(str);
            }
            params.put("gids", jSONArray.toString());
        }
        String sign = requestHelper.getRequestSign(params);
        huPuService.getGroupThreadsList(sign, params, callback);
    }