peersim.reports
Class GraphObserver

java.lang.Object
  peersim.reports.GraphObserver

All Implemented Interfaces:

Control

Direct Known Subclasses:

BallExpansion, Clustering, ConnectivityObserver, DegreeStats, GraphPrinter, GraphStats, InetObserver, RandRemoval

public abstract class GraphObserver
extends java.lang.Object
implements Control

Class that provides functionality for observing graphs. It can efficiently create an undirected version of the graph, making sure it is updated only when the simulation has advanced already, and provides some common parameters.

Parameter Summary

protocol
The protocol to operate on.

undir
If defined, the undirected version of the graph will be analyzed.

undirected
Alias for "undir".

graphobserver.fast
If defined, the undirected version of the graph will be stored using much more memory but observers will be in general a few times faster.

Field Summary

protected Graph	g
protected GraphAlgorithms	ga
protected java.lang.String	name The name of this observer in the configuration
protected int	pid
protected boolean	undir

Constructor Summary

protected

GraphObserver(java.lang.String name) Standard constructor that reads the configuration parameters.

Method Summary

protected void

updateGraph() Sets g.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface peersim.core.Control

execute

Parameter Detail

protocol

The protocol to operate on.

undir

If defined, the undirected version of the graph will be analyzed. Not defined by default.

undirected

Alias for "undir".

graphobserver.fast

If defined, the undirected version of the graph will be stored using much more memory but observers will be in general a few times faster. As a consequence, it will not work with large graphs. Not defined by default. It is a static property, that is, it affects all graph observers that are used in a simulation. That is, it is not a parameter of any observer, the name should be specified as a standalone property.

Field Detail

name

protected final java.lang.String name

The name of this observer in the configuration

pid

protected final int pid

undir

protected final boolean undir

ga

protected final GraphAlgorithms ga

g

protected Graph g

Constructor Detail

GraphObserver

protected GraphObserver(java.lang.String name)

Standard constructor that reads the configuration parameters. Invoked by the simulation engine.

Parameters:

name - the configuration prefix for this class

Method Detail

updateGraph

protected void updateGraph()

Sets g. It MUST be called by any implementation of Control.execute() before doing anything else. Attempts to initialize g from a pre-calculated graph stored in a static field, but first it checks whether it needs to be updated. If the simulation time has progressed or it was calculated for a different protocol, then updates this static graph as well. The purpose of this mechanism is to save the time of constructing the graph if many observers are run on the same graph. Time savings can be very significant if the undirected version of the same graph is observed by many observers.