/**
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 Feb 16, 2012
*/
package com.bigdata.rdf.internal.encoder;
import com.bigdata.bop.IBindingSet;
import com.bigdata.rdf.internal.IV;
import com.bigdata.rdf.internal.IVCache;
import com.bigdata.rdf.model.BigdataValue;
/**
* Interface for decoding {@link IBindingSet}s comprised of {@link IV}s.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
* @see IBindingSetEncoder
*/
public interface IBindingSetDecoder {
/**
* Return <code>true</code> iff the {@link IVCache} associations are
* preserved by the encoder.
*/
boolean isValueCache();
/**
* Decode an {@link IBindingSet}.
* <p>
* The resolution step can be deferred when the decoded {@link IBindingSet}
* does not require the resolved {@link IVCache} associations. For example,
* we do not need the {@link IVCache} association in order to decide if two
* {@link IBindingSet}s can join. However, once we have a solution from a
* join, we may need to resolve the {@link IVCache} metadata for the joined
* solution.
*
* @param val
* The encoded IV[].
* @param off
* The starting offset.
* @param len
* The #of bytes of data to be decoded.
* @param resolveCachedValues
* When <code>true</code>, any decoded {@link IV}s will have
* their {@link IVCache} association resolved before the
* {@link IBindingSet} is returned to the caller. When
* <code>false</code>, the resolution step is not performed.
*
* @return The decoded {@link IBindingSet}.
*
* @see #resolveCachedValues(IBindingSet)
*/
IBindingSet decodeSolution(final byte[] val, final int off, final int len,
final boolean resolveCachedValues);
/**
* Resolve any {@link IV}s in the solution for which there are cached
* {@link BigdataValue}s to those values. This method may be used to resolve
* {@link IVCache} associations for {@link IBindingSet}s NOT produced by
* {@link #decodeSolution(byte[], int, int, boolean)}. For example, when
* joining a decoded solution with another solution, the resolution step may
* be deferred until we know whether or not the join was successful.
*
* @param bset
* A solution having {@link IV}s which need to be reunited with
* their cached {@link BigdataValue}s.
*/
void resolveCachedValues(final IBindingSet bset);
/**
* Release the state associated with the {@link IVBindingSetDecoder}.
*/
void release();
}