mirror of
https://github.com/yacy/yacy_search_server.git
synced 2024-09-21 00:00:13 +02:00
83792d9233
git-svn-id: https://svn.berlios.de/svnroot/repos/yacy/trunk@5722 6c8d7289-2bf4-0310-a012-ef5d649a1542
62 lines
2.8 KiB
Java
62 lines
2.8 KiB
Java
// AbstractBufferedIndex.java
|
|
// -----------------------------
|
|
// (C) 2009 by Michael Peter Christen; mc@yacy.net, Frankfurt a. M., Germany
|
|
// first published 16.3.2009 on http://yacy.net
|
|
//
|
|
// This is a part of YaCy, a peer-to-peer based web search engine
|
|
//
|
|
// $LastChangedDate: 2006-04-02 22:40:07 +0200 (So, 02 Apr 2006) $
|
|
// $LastChangedRevision: 1986 $
|
|
// $LastChangedBy: orbiter $
|
|
//
|
|
// LICENSE
|
|
//
|
|
// 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; either version 2 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// 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
|
|
|
|
package de.anomic.kelondro.text;
|
|
|
|
import java.io.IOException;
|
|
import java.util.Iterator;
|
|
import java.util.TreeSet;
|
|
|
|
import de.anomic.kelondro.order.Order;
|
|
|
|
public abstract class AbstractBufferedIndex extends AbstractIndex implements BufferedIndex {
|
|
|
|
public synchronized TreeSet<ReferenceContainer> references(final String startHash, final boolean rot, int count, boolean ram) throws IOException {
|
|
// creates a set of indexContainers
|
|
// this does not use the cache
|
|
final Order<ReferenceContainer> containerOrder = new ReferenceContainerOrder(this.ordering().clone());
|
|
containerOrder.rotate(ReferenceContainer.emptyContainer(startHash, 0));
|
|
final TreeSet<ReferenceContainer> containers = new TreeSet<ReferenceContainer>(containerOrder);
|
|
final Iterator<ReferenceContainer> i = references(startHash, rot, ram);
|
|
if (ram) count = Math.min(size(), count);
|
|
ReferenceContainer container;
|
|
// this loop does not terminate using the i.hasNex() predicate when rot == true
|
|
// because then the underlying iterator is a rotating iterator without termination
|
|
// in this case a termination must be ensured with a counter
|
|
// It must also be ensured that the counter is in/decreased every loop
|
|
while ((count > 0) && (i.hasNext())) {
|
|
container = i.next();
|
|
if ((container != null) && (container.size() > 0)) {
|
|
containers.add(container);
|
|
}
|
|
count--; // decrease counter even if the container was null or empty to ensure termination
|
|
}
|
|
return containers; // this may return less containers as demanded
|
|
}
|
|
|
|
}
|