code: public AVIMConversation getConversation(String conversationId, int convType) {
      AVIMConversation result = null;
      switch (convType) {
        case Conversation.CONV_TYPE_SYSTEM:
          result = getServiceConversation(conversationId);
          break;
        case Conversation.CONV_TYPE_TEMPORARY:
          result = getTemporaryConversation(conversationId);
          break;
        case Conversation.CONV_TYPE_TRANSIENT:
          result = getChatRoom(conversationId);
          break;
        default:
          result = getConversation(conversationId);
          break;
      }
      return result;
    }
docs: get conversation by id and type
  
  @param conversationId
  @param convType
  @return