+++ /dev/null
-/*
- * Copyright (c) 2003-2005 The BISON Project
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU Lesser General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * 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 Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
- *
- */
-
-package peersim.reports;
-
-import peersim.core.*;
-import peersim.config.Configuration;
-import peersim.graph.*;
-import peersim.util.IncrementalStats;
-import java.util.Map;
-import java.util.Iterator;
-
-/**
- * It tests the network for robustness to random node removal.
- * It does not actually remove
- * nodes, it is only an observer, so can be applied several times during the
- * simulation. A warning though: as a side effect it <em>may
- * shuffle the network</em> (see {@value #PAR_N}) so if this is an issue,
- * it should not be used,
- * or only after the simulation has finished.
- */
-public class RandRemoval extends GraphObserver
-{
-
-// ===================== fields =======================================
-// ====================================================================
-
-// XXX remove side effect
-/**
- * This parameter defines the number of runs of the iterative removal procedure
- * to get statistics. Look out: if set to a value larger than 1 then as a side
- * effect <em>the overlay will be shuffled</em>. Defaults to 1.
- * @config
- */
-private static final String PAR_N = "n";
-
-private final int n;
-
-// ===================== initialization ================================
-// =====================================================================
-
-/**
- * Standard constructor that reads the configuration parameters.
- * Invoked by the simulation engine.
- * @param name the configuration prefix for this class
- */
-public RandRemoval(String name)
-{
- super(name);
- n = Configuration.getInt(name + "." + PAR_N, 1);
-}
-
-// ====================== methods ======================================
-// =====================================================================
-
-/**
-* Prints results of node removal tests. The following experiment is
-* repeated {@value #PAR_N} times. From the graph 50%, 51%, ..., 99% of the nodes
-* are removed at random. For all percentages it is calculated what is
-* the maximal
-* clustersize (weakly connected clusters) and the number of
-* clusters in the remaining graph.
-* These values are averaged over the experiments, and for all 50 different
-* percentage values a line is printed that contains the respective averages,
-* first the average maximal cluster size, followed by the average number
-* of clusters.
-* @return always false
-*/
-public boolean execute()
-{
- if( n < 1 ) return false;
- updateGraph();
-
- System.out.println(name + ":");
-
- final int size = Network.size();
- final int steps = 50;
- IncrementalStats[] maxClust = new IncrementalStats[steps];
- IncrementalStats[] clustNum = new IncrementalStats[steps];
- for (int i = 0; i < steps; ++i) {
- maxClust[i] = new IncrementalStats();
- clustNum[i] = new IncrementalStats();
- }
- for (int j = 0; j < n; ++j) {
- PrefixSubGraph sg = new PrefixSubGraph(g);
- IncrementalStats stats = new IncrementalStats();
- for (int i = 0; i < steps; i++) {
- sg.setSize(size / 2 - i * (size / 100));
- Map clst = ga.weaklyConnectedClusters(sg);
- stats.reset();
- Iterator it = clst.values().iterator();
- while (it.hasNext()) {
- stats.add(((Integer) it.next()).intValue());
- }
- maxClust[i].add(stats.getMax());
- clustNum[i].add(clst.size());
- }
- if( j+1 < n ) Network.shuffle();
- }
- for (int i = 0; i < steps; ++i) {
- System.out.println(maxClust[i].getAverage() + " "
- + clustNum[i].getAverage());
- }
- return false;
-}
-
-}
