Java tutorial
/******************************************************************************* * Copyright (g) 2004, 2007 IBM Corporation and Cambridge Semantics Incorporated. * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * which accompanies this distribution, and is available at * http://www.eclipse.org/legal/epl-v10.html * * File: $Source: /cvsroot/slrp/boca/com.ibm.adtech.boca.client/src/com/ibm/adtech/boca/client/Attic/TrackerManager.java,v $ * Created by: Matthew Roy ( <a href="mailto:mroy@us.ibm.com">mroy@us.ibm.com </a>) * Created on: Apr 16, 2007 * Revision: $Id: TrackerManager.java 179 2007-07-31 14:22:34Z mroy $ * * Contributors: * IBM Corporation - initial API and implementation * Cambridge Semantics Incorporated - Fork to Anzo *******************************************************************************/ package org.openanzo.combus.realtime; import java.util.Collection; import java.util.Comparator; import java.util.List; import java.util.Set; import java.util.concurrent.CopyOnWriteArrayList; import org.apache.commons.collections15.MultiMap; import org.openanzo.rdf.Resource; import org.openanzo.rdf.URI; import org.openanzo.rdf.Value; import org.openanzo.rdf.utils.CopyOnWriteMultiHashMap; import org.openanzo.services.impl.SelectorTracker; /** * The trackerManager keeps track of trackers, and provides indexer matching to find trackers that match statements. * * @param <T> * Type of tracker * @author Matthew Roy ( <a href="mailto:mroy@cambridgesemantics.com">mroy@cambridgesemantics.com </a>) * */ public class TrackerManager<T extends SelectorTracker> { protected final List<T> trackers; protected final MultiMap<URI, T> namedGraphMap; protected final MultiMap<Resource, T> subjectMap; protected final MultiMap<URI, T> propMap; protected final MultiMap<Value, T> objMap; protected final List<T> allWildTrackers; /** * Create a new TrackerManager */ public TrackerManager() { trackers = new CopyOnWriteArrayList<T>(); subjectMap = new CopyOnWriteMultiHashMap<Resource, T>(); propMap = new CopyOnWriteMultiHashMap<URI, T>(); objMap = new CopyOnWriteMultiHashMap<Value, T>(); namedGraphMap = new CopyOnWriteMultiHashMap<URI, T>(); allWildTrackers = new CopyOnWriteArrayList<T>(); } /** * Clear the contents of trackers and all indexes. */ public void clear() { trackers.clear(); namedGraphMap.clear(); subjectMap.clear(); propMap.clear(); objMap.clear(); allWildTrackers.clear(); } /** * Get the size of the trackers * * @return the size of the trackers */ public int size() { return trackers.size(); } /** * @return true if empty */ public boolean isEmpty() { return trackers.isEmpty(); } /** * Add a new tracker and index it * * @param tracker * to add */ public void addTracker(T tracker) { trackers.add(tracker); addMaps(tracker); } /** * Remove a tracker and remove it from the indexes * * @param tracker * tracker to remove */ public void removeTracker(T tracker) { trackers.remove(tracker); removeMaps(tracker); } protected void addMaps(T tracker) { Set<URI> g = tracker.getNamedGraphUri(); Set<Resource> s = tracker.getSubject(); Set<URI> p = tracker.getPredicate(); Set<Value> o = tracker.getObject(); if (s != null && !s.isEmpty()) { for (Resource _s : s) { subjectMap.put(_s, tracker); } } if (p != null && !p.isEmpty()) { for (URI _p : p) { propMap.put(_p, tracker); } } if (o != null && !o.isEmpty()) { for (Value _o : o) { objMap.put(_o, tracker); } } if (g != null && !g.isEmpty()) { for (URI ng : g) { namedGraphMap.put(ng, tracker); } } if ((s == null || s.isEmpty()) && (p == null || p.isEmpty()) && (o == null || o.isEmpty()) && (g == null || g.isEmpty())) { allWildTrackers.add(tracker); } } protected void removeMaps(T tracker) { Set<URI> g = tracker.getNamedGraphUri(); Set<Resource> s = tracker.getSubject(); Set<URI> p = tracker.getPredicate(); Set<Value> o = tracker.getObject(); if (s != null && !s.isEmpty()) { for (Resource _s : s) { subjectMap.remove(_s, tracker); } } if (p != null && !p.isEmpty()) { for (URI _p : p) { propMap.remove(_p, tracker); } } if (o != null && !o.isEmpty()) { for (Value _o : o) { objMap.remove(_o, tracker); } } if (g != null && !g.isEmpty()) { for (URI ng : g) { namedGraphMap.remove(ng, tracker); } } if ((s == null || s.isEmpty()) && (p == null || p.isEmpty()) && (o == null || o.isEmpty()) && (g == null || g.isEmpty())) { allWildTrackers.remove(tracker); } } static class StmtSetComp implements Comparator<Collection<?>> { public int compare(Collection<?> o1, Collection<?> o2) { int result = 0; if (o1.size() == o2.size()) return result; return (o1.size() < o2.size()) ? -1 : 1; } } }