simulator.java

peersim最新版1.0.4

/*
 * 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;

import java.io.*;

import peersim.cdsim.*;
import peersim.config.*;
import peersim.core.*;
import peersim.edsim.*;


/**
* This is the main entry point to peersim. This class loads configuration and
* detects the simulation type. According to this, it invokes the appropriate
* simulator. The known simulators at this moment, along with the way to
* detect them are the following:
* <ul>
* <li>{@link CDSimulator}:
* if {@link CDSimulator#isConfigurationCycleDriven} returns
* true</li>
* <li>{@link EDSimulator}:
* if {@link EDSimulator#isConfigurationEventDriven} returns
* true
* </li>
* </ul>
* This list represents the order in which these alternatives are checked.
* That is, if more than one return true, then the first will be taken.
* Note that this class checks only for these clues and does not check if the
* configuration is consistent or valid.
* @see #main
*/
public class Simulator {

// ========================== static constants ==========================
// ======================================================================

/** {@link CDSimulator} */
public static final int CDSIM = 0;

/** {@link EDSimulator} */
public static final int EDSIM = 1;

/** Unknown simulator */
public static final int UNKNOWN = -1;

/** the class names of simulators used */
protected static final String[] simName = {
	"peersim.cdsim.CDSimulator",
	"peersim.edsim.EDSimulator",
};

/**
 * Parameter representing the number of times the experiment is run.
 * Defaults to 1.
 * @config
 */
public static final String PAR_EXPS = "simulation.experiments";
	
/**
 * If present, this parameter activates the redirection of the standard
 * output to a given PrintStream.
 * This comes useful for processing the output of the simulation from
 * within the simulator.
 * @config
 */
public static final String PAR_REDIRECT = "simulation.stdout";

// ==================== static fields ===================================
// ======================================================================

/** */
private static int simID = UNKNOWN;

//========================== methods ===================================
//======================================================================

/**
* Returns the numeric id of the simulator to invoke. At the moment this can
* be {@link #CDSIM}, {@link #EDSIM} or {@link #UNKNOWN}.
*/
public static int getSimID() {
	
	if (simID == UNKNOWN) {
		if( CDSimulator.isConfigurationCycleDriven()){
			simID = CDSIM;
		}
		else if( EDSimulator.isConfigurationEventDriven() ) {	
			simID = EDSIM;
		}
	}
	return simID;
}

// ----------------------------------------------------------------------

/**
* Loads the configuration and executes the experiments.
* The number of independent experiments is given by config parameter
* {@value #PAR_EXPS}. In all experiments the configuration is the same,
* only the random seed is not re-initialized between experiments.
* <p>
* Loading the configuration is currently done with the help of constructing
* an instance of {@link ParsedProperties} using the constructor
* {@link ParsedProperties#ParsedProperties(String[])}.
* The parameter
* <code>args</code> is simply passed to this class. This class is then used
* to initialize the configuration.
* <p>
* After loading the configuration, the experiments are run by invoking the
* appropriate engine, which is identified as follows:
* <ul>
* <li>{@link CDSimulator}:
* if {@link CDSimulator#isConfigurationCycleDriven} returns
* true</li>
* <li>{@link EDSimulator}:
* if {@link EDSimulator#isConfigurationEventDriven} returns
* true
* </li>
* </ul>
* <p>
* This list represents the order in which these alternatives are checked.
* That is, if more than one return true, then the first will be taken.
* Note that this class checks only for these clues and does not check if the
* configuration is consistent or valid.
* @param args passed on to
* {@link ParsedProperties#ParsedProperties(String[])}
* @see ParsedProperties
* @see Configuration
* @see CDSimulator
* @see EDSimulator
*/
public static void main(String[] args)
{
	long time = System.currentTimeMillis();	
	
	System.err.println("Simulator: loading configuration");
	Configuration.setConfig( new ParsedProperties(args) );

	PrintStream newout =
		(PrintStream)Configuration.getInstance(PAR_REDIRECT,System.out);
	if(newout!=System.out) System.setOut(newout);
	
	int exps = Configuration.getInt(PAR_EXPS,1);

	final int SIMID = getSimID();
	if( SIMID == UNKNOWN )
	{
		System.err.println(
		    "Simulator: unable to identify configuration, exiting.");
		return;
	}
	
	try {

		for(int k=0; k<exps; ++k)
		{
			if( k>0 )
			{
				long seed = CommonState.r.nextLong();
				CommonState.initializeRandom(seed);
			}
			System.err.print("Simulator: starting experiment "+k);
			System.err.println(" invoking "+simName[SIMID]);
			System.err.println("Random seed: "+
				CommonState.r.getLastSeed());
			System.out.println("\n\n");
			
			// XXX could be done through reflection, but
			// this is easier to read.
			switch(SIMID)
			{
			case CDSIM:
				CDSimulator.nextExperiment();
				break;
			case EDSIM:
				EDSimulator.nextExperiment();
				break;
			}
		}
	
	} catch (MissingParameterException e) {
		System.err.println(e+"");
		System.exit(1);
	} catch (IllegalParameterException e) {
		System.err.println(e+"");
		System.exit(1);
	}

	// undocumented testing capabilities
	if(Configuration.contains("__t")) 
		System.out.println(System.currentTimeMillis()-time);
	if(Configuration.contains("__x")) Network.test();
	
	
	
}

}