code: public final int getPersistableInMemorySizeApproximation(TransactionState tranState)
      {
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) SibTr.entry(this, tc, "getPersistableInMemorySizeApproximation", tranState);
  
          int size;
  
          if ((tranState == TransactionState.STATE_COMMITTED) || (tranState == TransactionState.STATE_COMMITTING_1PC))
          {
              size = DEFAULT_TASK_PERSISTABLE_SIZE_APPROXIMATION;
          }
          else
          {
              throw new IllegalStateException(nls.getFormattedMessage("INVALID_TASK_OPERATION_SIMS1520", new Object[] {tranState}, null));
          }
  
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled()) SibTr.exit(this, tc, "getPersistableInMemorySizeApproximation", Integer.valueOf(size));
          return size;
      }
docs: /*
  (non-Javadoc)
  @see com.ibm.ws.sib.msgstore.persistence.Operation#getPersistableInMemorySizeApproximation(int)