将请求参数组装成待验签的字符串
private static String sortJsonAsString(JSONObject obj){ JSONObject json = new JSONObject(); json.putAll(obj); Set<String> keySet = json.keySet(); keySet.remove(IGNORE_KEY_TOKEN); keySet.remove(IGNORE_KEY_SIGN); if(keySet.isEmpty()){ return null; } String[] keys = new String[keySet.size()]; keySet.toArray(keys); Arrays.sort(keys); StringBuffer sb = new StringBuffer(); for(String key : keys){ sb.append(key +"="+ json.getString(key)); if(!key.equals(keys[keys.length-1])){ sb.append("&"); } } return sb.toString(); }