code: @Override
      public int getInMemoryDataSize()
      {
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.entry(this, tc, "getInMemoryDataSize");
  
          JsMessage localMsg = getJSMessage(true);
          int msgSize = localMsg.getInMemorySize();
  
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.exit(this, tc, "getInMemoryDataSize", Integer.valueOf(msgSize));
  
          return msgSize;
      }
docs: Returns an estimated in memory size for the Message that we have.