/**
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 Jun 13, 2010
*/
package com.bigdata.ha;
import java.io.IOException;
import java.rmi.Remote;
import java.util.UUID;
import java.util.concurrent.Future;
import com.bigdata.ha.msg.IHAReadRequest;
import com.bigdata.ha.msg.IHAReadResponse;
import com.bigdata.rawstore.IRawStore;
/**
* A {@link Remote} interface supporting low-level reads against persistent data
* from a quorum member. This interface is used to handle bad reads, which are
* identified by a checksum error when reading on the local disk. To handle a
* bad read, the quorum member reads on a different member of the same quorum.
*
* @see QuorumRead
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
public interface HAReadGlue extends Remote {
/**
* Read a record an {@link IRawStore} managed by the service. Services MUST
* NOT refer this message to another service. If the read can not be
* satisfied, for example because the {@link IRawStore} has been released or
* because there is a checksum error when reading on the {@link IRawStore},
* then that exception should be thrown back to the caller.
*
* @param readMessage
* The {@link IHAReadRequest}.
*
* @return The {@link Future} of an operation which evaluated to the desired
* record.
*
* @see QuorumRead#readFromQuorum(UUID, long)
*/
public Future<IHAReadResponse> readFromDisk(IHAReadRequest readMessage)
throws IOException;
}