code: void updateDataFields(int why) {
      if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) SibTr.entry(this, tc, "updateDataFields");
      super.updateDataFields(why);
      if (bodyMap != null && bodyMap.isChanged()) {
        getPayload().setField(JmsMapBodyAccess.BODY_DATA_ENTRY_NAME, bodyMap.getKeyList());
        getPayload().setField(JmsMapBodyAccess.BODY_DATA_ENTRY_VALUE, bodyMap.getValueList());
        bodyMap.setUnChanged();                                                   // d317373.1
      }
      if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) SibTr.exit(this, tc, "updateDataFields");
    }
docs: Helper method used by the JMO to rewrite any transient data back into the
  underlying JMF message.
  
  @param why The reason for the update
  @see com.ibm.ws.sib.mfp.MfpConstants