docs: public MessageDataDesc getMessageDataDesc(String strParam)
      {
          if (strParam == null)
              return this;
          if (strParam.equals(this.getKey()))
              return this;
          if (m_messageDataDescChildren == null)
          {
              m_messageDataDescChildren = new HashMap<String,MessageDataDesc>();
              this.setupMessageDataDesc();
          }
          return (MessageDataDesc)m_messageDataDescChildren.get(strParam);
      }