Added percentile-based lifetime generator

src/de/tudarmstadt/maki/simonstrator/api/component/sensor/environment/generator/lifetime/DeterministicExponentialLifetimeDistribution.java

+/*
+ * Copyright (c) 2005-2010 KOM – Multimedia Communications Lab
+ *
+ * This file is part of Simonstrator.KOM.
+ * 
+ * Simonstrator.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.tudarmstadt.maki.simonstrator.api.component.sensor.environment.generator.lifetime;
+
+import de.tudarmstadt.maki.simonstrator.api.Time;
+import de.tudarmstadt.maki.simonstrator.api.util.XMLConfigurableConstructor;
+
+public class DeterministicExponentialLifetimeDistribution implements LifetimeDistribution {
+	private long _averageEventDuration;
+	private double _existProbability;
+
+	private double _percentile;
+
+	@XMLConfigurableConstructor({ "duration", "percentile" })
+	public DeterministicExponentialLifetimeDistribution(long pEventDuration, double pPercentile) {
+		_averageEventDuration = pEventDuration;
+
+		_existProbability = 1 - 1 / (double) (pEventDuration / Time.SECOND);
+
+		_percentile = pPercentile;
+	}
+
+	@Override
+	public long getLifetime() {
+		return (long) Math.ceil(Math.log(_percentile) / Math.log(_existProbability)) * Time.SECOND;
+	}
+
+	@Override
+	public long getAverageLifetime() {
+		return _averageEventDuration;
+	}
+}