code: @Override
  	public void setTransactionIsolation(int level) throws RemoteException {
  		if (getAutoCommit() != false)
  			throw new RemoteException(
  					"the auto-commit mode need to be set to false before changing the isolation level");
  		if (this.isolationLevel == level)
  			return;
  		tx.commit();
  		this.isolationLevel = level;
  		try {
  			tx = VanillaDb.txMgr().newTransaction(isolationLevel, readOnly);
  		} catch (Exception e) {
  			throw new RemoteException("error creating transaction ", e);
  		}
  	}
docs: Attempts to change the transaction isolation level for this connection.
  This method will commit current transaction and start a new transaction.
  Currently, the only supported isolation levels are
  {@link Connection#TRANSACTION_SERIALIZABLE} and
  {@link Connection#TRANSACTION_REPEATABLE_READ}. The auto-commit mode must
  be set to false before calling this method.