/*
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 Mar 12, 2008
*/
package com.bigdata.resources;
import org.apache.log4j.Logger;
import com.bigdata.journal.AbstractTask;
import com.bigdata.journal.ITx;
import com.bigdata.service.IDataService;
import com.bigdata.service.IMetadataService;
/**
* Abstract base class for tasks run during post-processing of a journal by the
* {@link ResourceManager}. These tasks are designed with a historical read
* that handles history up to some specified commitTime and the submits an
* {@link ITx#UNISOLATED} task that brings things up to date and coordinates an
* atomic update between the {@link IDataService}(s) and the
* {@link IMetadataService}. You SHOULD be able to run any task at any time as
* long as overflow is disabled while these tasks are running (this is a
* pre-condition for all of these tasks).
*
* FIXME There is a potential failure point once we notify the metadata service
* of the change in the index partitions since this is done before the task has
* actually committed its changes on the live journal. If the commit on the
* journal fails then the metadata index will now reference index partitions
* which do not exist (or do not have all their data) on the live journal. A
* full transaction might be one way to close this gap. The opportunity for
* failure could be significantly reduced by checkpointing all indices before we
* RMI the MDS.
*
* @author <a href="mailto:thompsonbry@users.sourceforge.net">Bryan Thompson</a>
* @version $Id$
*/
abstract public class AbstractResourceManagerTask<T> extends AbstractTask<T> {
/**
* Note: Logger shadows {@link AbstractTask#log}.
*/
static protected final Logger log = Logger.getLogger(AbstractResourceManagerTask.class);
/**
* True iff the {@link #log} level is INFO or less.
*/
static final protected boolean INFO = log.isInfoEnabled();
/**
* True iff the {@link #log} level is DEBUG or less.
*/
static final protected boolean DEBUG = log.isDebugEnabled();
protected final ResourceManager resourceManager;
/**
* @param resourceManager
* @param timestamp
* @param resource
*/
public AbstractResourceManagerTask(final ResourceManager resourceManager,
final long timestamp, final String resource) {
super(resourceManager.getConcurrencyManager(), timestamp, resource);
this.resourceManager = resourceManager;
}
/**
* @param resourceManager
* @param timestamp
* @param resource
*/
public AbstractResourceManagerTask(ResourceManager resourceManager,
long timestamp, String[] resource) {
super(resourceManager.getConcurrencyManager(), timestamp, resource);
this.resourceManager = resourceManager;
}
/**
* Pretty print a resource metadata array or other array of objects with
* long string representations by framing the output to have one line
* for each element of the array.
*
* @param label
* A label.
* @param a
* The array.
*
* @return The pretty printed string.
*/
static public String toString(final String label, final Object[] a) {
StringBuilder sb = new StringBuilder();
sb.append("\n");
sb.append(label);
sb.append("(" + a.length + ")=[");
for (Object t : a) {
sb.append("\n");
sb.append(t.toString());
sb.append(",");
}
sb.append("]");
return sb.toString();
}
}