/**
Copyright (C) SYSTAP, LLC DBA Blazegraph 2006-2016. All rights reserved.
Contact:
SYSTAP, LLC DBA Blazegraph
2501 Calvert ST NW #106
Washington, DC 20008
licenses@blazegraph.com
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
/*
* Created on Aug 6, 2011
*/
package com.bigdata.bop;
import java.util.UUID;
import com.bigdata.htree.HTree;
import com.bigdata.rwstore.sector.IMemoryManager;
/**
* Context for the evaluation of a query pipeline.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
*/
public interface IQueryContext {
/**
* The unique identifier for the query.
*/
UUID getQueryId();
/**
* Return the {@link IMemoryManager} which may be used to buffer data on
* high level data structures, such as the {@link HTree}, for this query.
* Each operator in the query should in general create its own child
* {@link IMemoryManager}. While the overall {@link IMemoryManager} context
* associated with a query will be released when the query terminates,
* operators which create child {@link IMemoryManager} contexts are
* responsible for releasing their {@link IMemoryManager} in a timely
* fashion when the operator has finished its evaluation.
*/
IMemoryManager getMemoryManager();
/**
* Return an interface which allows attribute values to be associated with
* an {@link IQueryContext}.
*/
IQueryAttributes getAttributes();
}