Added cache based decision

src/de/tud/kom/p2psim/impl/vehicular/caching/DefaultCachingComponent.java

@@ -30,8 +30,10 @@ import de.tudarmstadt.maki.simonstrator.api.component.network.NetInterface;
 import de.tudarmstadt.maki.simonstrator.api.component.network.NetworkComponent.NetInterfaceName;
 import de.tudarmstadt.maki.simonstrator.api.component.transport.ConnectivityListener;
 import de.tudarmstadt.maki.simonstrator.api.component.vehicular.caching.CachingComponent;
+import de.tudarmstadt.maki.simonstrator.api.component.vehicular.caching.decision.CacheDecisionStrategy;
 import de.tudarmstadt.maki.simonstrator.api.component.vehicular.caching.invalidation.CacheInvalidationStrategy;
 import de.tudarmstadt.maki.simonstrator.api.component.vehicular.caching.replacement.CacheReplacementStrategy;
+import de.tudarmstadt.maki.simonstrator.api.component.vehicular.information.AvailableInformationAttributes;
 import de.tudarmstadt.maki.simonstrator.api.component.vehicular.information.PointInformation;
 
 public class DefaultCachingComponent implements CachingComponent, ConnectivityListener {
@@ -40,14 +42,50 @@ public class DefaultCachingComponent implements CachingComponent, ConnectivityLi
 
 	private CacheInvalidationStrategy _invalidationStrategy;
 	private CacheReplacementStrategy _replacementStrategy;
+	private CacheDecisionStrategy _decisionStrategy;
 
-	public DefaultCachingComponent(Host pHost, CacheInvalidationStrategy pInvalidationStrategy, CacheReplacementStrategy pReplacementStrategy) {
+	public DefaultCachingComponent(Host pHost, CacheInvalidationStrategy pInvalidationStrategy, CacheReplacementStrategy pReplacementStrategy, CacheDecisionStrategy pDecisionStrategy) {
 		_host = pHost;
 
+		if (_host != null) {
 			_host.getNetworkComponent().getByName(NetInterfaceName.WIFI).addConnectivityListener(this);
+		}
 
 		_invalidationStrategy = pInvalidationStrategy;
 		_replacementStrategy = pReplacementStrategy;
+		_decisionStrategy = pDecisionStrategy;
+	}
+
+	@Override
+	public <T extends PointInformation> List<T> getDecidedCacheEntries(Class<T> pCacheEntryClass) {
+		List<T> cacheEntries = getCacheEntries(pCacheEntryClass);
+
+		if (cacheEntries == null) {
+			return null;
+		}
+
+		Map<Object, List<PointInformation>> similarCacheEntries = new HashMap<>();
+
+		for (T t : cacheEntries) {
+			Object position = getEdgeOrPosition(t);
+			if (!similarCacheEntries.containsKey(position)) {
+				similarCacheEntries.put(position, new ArrayList<>());
+			}
+			similarCacheEntries.get(position).add(t);
+		}
+
+		List<T> decidedInformation = new ArrayList<>();
+		for (List<PointInformation> similarEntries : similarCacheEntries.values()) {
+			PointInformation correctInformation = _decisionStrategy.decideOnCorrectInformation(similarEntries);
+
+			if (correctInformation == null) {
+				System.out.println();
+			}
+
+			decidedInformation.add((T) correctInformation);
+		}
+
+		return decidedInformation;
 	}
 
 	@Override
@@ -85,17 +123,7 @@ public class DefaultCachingComponent implements CachingComponent, ConnectivityLi
 			_cache.put(pCacheEntry.getClass(), new ArrayList<>());
 		}
 		List<PointInformation> entries = _cache.get(pCacheEntry.getClass());
-		int index;
-		if ((index = entries.indexOf(pCacheEntry)) != -1) {
-			if (_replacementStrategy.replaceInformation(entries.get(index), pCacheEntry)) {
-				entries.remove(index);
 		entries.add(pCacheEntry);
-			} else {
-				// Nothing to do
-			}
-		} else {
-			entries.add(pCacheEntry);
-		}
 	}
 
 	@Override
@@ -127,4 +155,12 @@ public class DefaultCachingComponent implements CachingComponent, ConnectivityLi
 		_cache.clear();
 	}
 
+	public Object getEdgeOrPosition(PointInformation information) {
+		if (information.hasAttribute(AvailableInformationAttributes.EDGE)) {
+			return information.getAttribute(AvailableInformationAttributes.EDGE);
+		} else {
+			return information.getLocation();
+		}
+	}
+
 }

src/de/tud/kom/p2psim/impl/vehicular/caching/decision/CacheDecisionStrategyType.java

+/*
+ * Copyright (c) 2005-2010 KOM – Multimedia Communications Lab
+ *
+ * This file is part of PeerfactSim.KOM.
+ *
+ * PeerfactSim.KOM 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 3 of the License, or
+ * any later version.
+ *
+ * PeerfactSim.KOM 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 PeerfactSim.KOM.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package de.tud.kom.p2psim.impl.vehicular.caching.decision;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.util.HashMap;
+import java.util.Map;
+
+import de.tudarmstadt.maki.simonstrator.api.component.vehicular.caching.decision.CacheDecisionStrategy;
+
+public enum CacheDecisionStrategyType {
+	DEFAULT(NewestCacheDecisionStrategy.class), NEWEST(NewestCacheDecisionStrategy.class), TTL(TTLbasedCacheDecisionStrategy.class), MAJORITY(MajorityVotingCacheDecisionStrategy.class);
+
+	private final Class<? extends CacheDecisionStrategy> decisionStrategy;
+	private final Map<String, String> params = new HashMap<>();
+
+	private CacheDecisionStrategyType(final Class<? extends CacheDecisionStrategy> decisionStrategy) {
+		this.decisionStrategy = decisionStrategy;
+	}
+
+	public CacheDecisionStrategy getDecisionStrategy() {
+		try {
+			try {
+				Constructor<? extends CacheDecisionStrategy> constructor = decisionStrategy.getConstructor(Map.class);
+				return constructor.newInstance(params);
+			} catch (NoSuchMethodException | SecurityException | IllegalArgumentException | InvocationTargetException e) {
+				return decisionStrategy.newInstance();
+			}
+		} catch (InstantiationException | IllegalAccessException e) {
+			throw new AssertionError(e);
+		}
+	}
+
+	public void addAttribute(String pKey, String pValue) {
+		params.put(pKey, pValue);
+	}
+}

src/de/tud/kom/p2psim/impl/vehicular/caching/decision/MajorityVotingCacheDecisionStrategy.java

+/*
+ * Copyright (c) 2005-2010 KOM – Multimedia Communications Lab
+ *
+ * This file is part of PeerfactSim.KOM.
+ *
+ * PeerfactSim.KOM 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 3 of the License, or
+ * any later version.
+ *
+ * PeerfactSim.KOM 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 PeerfactSim.KOM.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package de.tud.kom.p2psim.impl.vehicular.caching.decision;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import de.tudarmstadt.maki.simonstrator.api.component.vehicular.caching.decision.CacheDecisionStrategy;
+import de.tudarmstadt.maki.simonstrator.api.component.vehicular.information.PointInformation;
+
+public class MajorityVotingCacheDecisionStrategy implements CacheDecisionStrategy {
+
+	@Override
+	public <T extends PointInformation> T decideOnCorrectInformation(
+			List<T> pSimilarPointInformation) {
+
+		Map<Object, Integer> voting = new HashMap<>();
+		for (T t : pSimilarPointInformation) {
+			if (!voting.containsKey(t.getValue())) {
+				voting.put(t.getValue(), 0);
+			}
+
+			voting.put(t.getValue(), voting.get(t.getValue()) + 1);
+		}
+
+		Entry<Object, Integer> maxEntry = null;
+		for (Entry<Object, Integer> entry : voting.entrySet()) {
+			if (maxEntry == null) {
+				maxEntry = entry;
+			}
+
+			if (maxEntry.getValue() < entry.getValue()) {
+				maxEntry = entry;
+			}
+		}
+
+		long maxTimestamp = 0;
+		T maxFitting = null;
+		for (T t : pSimilarPointInformation) {
+			long timestamp = t.getDetectionDate();
+
+			if (t.getValue().equals(maxEntry.getValue()) && timestamp > maxTimestamp) {
+				maxTimestamp = timestamp;
+				maxFitting = t;
+			}
+		}
+
+		return maxFitting;
+	}
+
+}

src/de/tud/kom/p2psim/impl/vehicular/caching/decision/NewestCacheDecisionStrategy.java

+/*
+ * Copyright (c) 2005-2010 KOM – Multimedia Communications Lab
+ *
+ * This file is part of PeerfactSim.KOM.
+ *
+ * PeerfactSim.KOM 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 3 of the License, or
+ * any later version.
+ *
+ * PeerfactSim.KOM 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 PeerfactSim.KOM.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package de.tud.kom.p2psim.impl.vehicular.caching.decision;
+
+import java.util.List;
+
+import de.tudarmstadt.maki.simonstrator.api.component.vehicular.caching.decision.CacheDecisionStrategy;
+import de.tudarmstadt.maki.simonstrator.api.component.vehicular.information.PointInformation;
+
+public class NewestCacheDecisionStrategy implements CacheDecisionStrategy {
+
+	@Override
+	public <T extends PointInformation> T decideOnCorrectInformation(
+			List<T> pSimilarPointInformation) {
+		long newestDetectionTime = 0;
+		T chosenInformation = null;
+		for (T t : pSimilarPointInformation) {
+			if (t.getDetectionDate() > newestDetectionTime) {
+				newestDetectionTime = t.getDetectionDate();
+				chosenInformation = t;
+			}
+		}
+		return chosenInformation;
+	}
+
+}

src/de/tud/kom/p2psim/impl/vehicular/caching/decision/TTLbasedCacheDecisionStrategy.java

+/*
+ * Copyright (c) 2005-2010 KOM – Multimedia Communications Lab
+ *
+ * This file is part of PeerfactSim.KOM.
+ *
+ * PeerfactSim.KOM 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 3 of the License, or
+ * any later version.
+ *
+ * PeerfactSim.KOM 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 PeerfactSim.KOM.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package de.tud.kom.p2psim.impl.vehicular.caching.decision;
+
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+
+import de.tudarmstadt.maki.simonstrator.api.Time;
+import de.tudarmstadt.maki.simonstrator.api.component.vehicular.caching.decision.CacheDecisionStrategy;
+import de.tudarmstadt.maki.simonstrator.api.component.vehicular.information.AvailableInformationAttributes;
+import de.tudarmstadt.maki.simonstrator.api.component.vehicular.information.PointInformation;
+
+public class TTLbasedCacheDecisionStrategy implements CacheDecisionStrategy {
+	private static final long SCALING = Time.SECOND;
+
+	private long ttl = 300 * Time.SECOND / SCALING;
+	private double accuracy = 1;
+
+	private double costWrongKeep = 1;
+	private double costWrongChange = 1;
+
+	public TTLbasedCacheDecisionStrategy(Map<String, String> pParams) {
+		for (Entry<String, String> param : pParams.entrySet()) {
+			switch (param.getKey()) {
+			case "ACCURACY":
+				accuracy = Double.valueOf(param.getValue());
+				break;
+			default:
+				break;
+			}
+		}
+	}
+
+	@Override
+	public <T extends PointInformation> T decideOnCorrectInformation(
+			List<T> pSimilarPointInformation) {
+		if (pSimilarPointInformation.size() == 1) {
+			return pSimilarPointInformation.get(0);
+		} else if (pSimilarPointInformation.size() == 0) {
+			return null;
+		}
+
+		long minTimestamp = Long.MAX_VALUE;
+		long maxTimestamp = 0;
+		Object value = pSimilarPointInformation.get(0).getValue();
+		boolean differentValue = false;
+		for (T t : pSimilarPointInformation) {
+			if (!t.hasAttribute(AvailableInformationAttributes.TTL)) {
+				throw new AssertionError("Unable to perform TTL-based majority voting witout TTL");
+			}
+			long timestamp = t.getDetectionDate();
+
+			if (timestamp < minTimestamp) {
+				minTimestamp = timestamp;
+			}
+			if (timestamp > maxTimestamp) {
+				maxTimestamp = timestamp;
+			}
+
+			if (!value.equals(t.getValue())) {
+				differentValue = true;
+			}
+		}
+
+		if (differentValue) {
+			long difference = maxTimestamp - minTimestamp;
+
+			if (difference == 0) {
+				return pSimilarPointInformation.get(pSimilarPointInformation.size() - 1);
+			}
+
+			double rate = difference / ((double) (pSimilarPointInformation.size() - 1) * SCALING);
+
+			rate = Math.min(rate, ttl / 10);
+
+			double b = determineB(rate, 1 - accuracy, ttl, costWrongKeep, costWrongChange);
+
+			Map<Object, Double> weight = new HashMap<>();
+
+			for (T t : pSimilarPointInformation) {
+				double impact = calculateImpact(1 - accuracy, ttl, t.getDetectionDate() / SCALING, b, maxTimestamp / SCALING);
+
+				double sumImpact = 0;
+
+				if (weight.containsKey(t.getValue())) {
+					sumImpact = weight.get(t.getValue());
+				}
+				sumImpact += impact;
+
+				weight.put(t.getValue(), sumImpact);
+			}
+
+			double maxWeight = 0;
+			Object maxValue = null;
+
+			for (Object key : weight.keySet()) {
+				if (weight.get(key) > maxWeight) {
+					maxWeight = weight.get(key);
+					maxValue = key;
+				}
+			}
+
+			maxTimestamp = 0;
+			T maxFitting = null;
+			for (T t : pSimilarPointInformation) {
+				long timestamp = t.getDetectionDate();
+
+				if (t.getValue().equals(maxValue) && timestamp > maxTimestamp) {
+					maxTimestamp = timestamp;
+					maxFitting = t;
+				}
+			}
+
+			return maxFitting;
+		} else {
+			maxTimestamp = 0;
+			T maxFitting = null;
+			for (T t : pSimilarPointInformation) {
+				long timestamp = (long) t.getAttribute(AvailableInformationAttributes.TTL);
+
+				if (timestamp > maxTimestamp) {
+					maxTimestamp = timestamp;
+					maxFitting = t;
+				}
+			}
+
+			return maxFitting;
+		}
+	}
+
+	public double calculateImpact(double errorProbability, long ttl, long time, double b, long maxTimestamp) {
+		long currentTime = Time.getCurrentTime() / SCALING;
+		long age = currentTime - time;
+		if (errorProbability == 0) {
+			if (time == maxTimestamp) {
+				return 1;
+			} else {
+				return 0;
+			}
+		} else if (errorProbability == 1) {
+			return 1;
+		} else if (errorProbability == 0.5) {
+			return (errorProbability - 1) / ttl * age + errorProbability;
+		}
+
+		return (1 - errorProbability) * (Math.exp(b * age) - Math.exp(b * ttl)) / (1 - Math.exp(b * ttl));
+	}
+
+	public double getChangeProbability(long ttl) {
+		return 1 - Math.pow(0.5, 1 / (double) ttl);
+	}
+
+	public int getOptimalMessageAmountForSwitch(double changeProbability, double errorProbability, double costSlow, double costFast) {
+		return (int) Math.round(Math.log(-changeProbability / Math.log(errorProbability) * costSlow / costFast) / Math.log(errorProbability));
+	}
+
+	public double determineB(double rate, double errorProbability, long ttl, double costSlow, double costFast) {
+		return determineB(rate, errorProbability, ttl, costSlow, costFast, 1);
+	}
+
+	public double determineB(double rate, double errorProbability, long ttl, double costSlow, double costFast, int reversed) {
+		if (errorProbability == 0 || errorProbability == 1 || errorProbability == 0.5) {
+			return Double.NaN;
+		}
+
+		double b;
+		double p_c = getChangeProbability((long) (ttl / rate));
+
+		int optimalAmount = getOptimalMessageAmountForSwitch(p_c, errorProbability, costSlow, costFast);
+
+		boolean first = true;
+
+		double leftSide;
+		double rightSide;
+
+		double step = 0.5;
+
+		if (errorProbability < 0.5) {
+			b = -1 * reversed;
+		} else {
+			b = 1 * reversed;
+		}
+
+		do {
+			leftSide = calculateWeightingForOldState(optimalAmount, rate, errorProbability, ttl, b);
+			rightSide = calculateWeightingForNewState(optimalAmount, rate, errorProbability, ttl, b);
+
+			if (Double.isNaN(leftSide) || Double.isNaN(rightSide)) {
+				if (reversed != -1) {
+					return determineB(rate, errorProbability, ttl, costSlow, costFast, -1);
+				} else {
+					return Double.NaN;
+				}
+			}
+
+			leftSide = Math.round(leftSide * 100000);
+			rightSide = Math.round(rightSide * 100000);
+
+			if (leftSide > rightSide) {
+				if (b < 0) {
+					b -= step;
+					if (!first) {
+						step *= 0.5;
+					}
+				} else {
+					b -= step;
+					step *= 0.5;
+					first = false;
+				}
+			} else if (leftSide < rightSide) {
+				if (b > 0) {
+					b += step;
+					if (!first) {
+						step *= 0.5;
+					}
+				} else {
+					b += step;
+					step *= 0.5;
+					first = false;
+				}
+			} else {
+				break;
+			}
+		} while (true);
+
+		return b;
+	}
+
+	public double calculateWeightingForOldState(int optimalMessageAmount, double rate, double errorProbability, long ttl, double b) {
+		double impact = 0;
+		for (int a = optimalMessageAmount + 1; a < Math.max(Math.floor(ttl / rate), optimalMessageAmount + 2); a++) {
+			impact += calculateImpact(errorProbability, ttl, Time.getCurrentTime() / SCALING - (long)Math.floor(a * rate), b, 0);
+		}
+		return impact;
+	}
+
+	public double calculateWeightingForNewState(int optimalMessageAmount, double rate, double errorProbability, long ttl, double b) {
+		double impact = 0;
+		for (int a = 0; a <= optimalMessageAmount; a++) {
+			impact += calculateImpact(errorProbability, ttl, Time.getCurrentTime() / SCALING - (long)Math.floor(a * rate), b, 0);
+		}
+		return impact;
+	}
+}