netcontroller.java

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/**    
  * Copyright (C) 2006, Laboratorio di Valutazione delle Prestazioni - Politecnico di Milano

  * This program 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 2 of the License, or
  * (at your option) any later version.

  * 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 General Public License for more details.

  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  */
  
package jmt.engine.QueueNet;

//import eduni.simjava.*;

import jmt.engine.simEngine.SimSystem;

/**
 * Controls the state of the simulation and determines when to stop the simulation.
 *
 * @author Federico Granata, Stefano Omini
 */

class NetController {

    private final boolean DEBUG = false;

	private boolean running;

	private double startTime, stopTime;

	private int stopLevel, abortLevel;

    //NEW
    //@author Stefano Omini

    //number of system "ticks"
    private int n;
    //check measures every refreshPeriod system ticks
    private int refreshPeriod = 12000;

    //check if some measures have not receive any sample yet
    //WARNING: this samples number must be a multiple of refreshPeriod!!
    private int reachabilityTest = refreshPeriod * 10;

    //log object
    //private NetLog log;
    //end NEW


    //NEW
    //@author Stefano Omini
    private boolean blocked = false;
    //end NEW


    NetController() {

        running = false;
        //NEW
        //@author Stefano Omini
        //initializes tick counter
        n = 0;
        //end NEW
	}


	/** This is the run method of the NetController (thread). */
	public void run() {

		//Date dateTime;
		//dateTime = new Date();


        try {
			SimSystem.runStart();
			startTime = NetSystem.getElapsedTime();

			while (SimSystem.runTick()) {

                synchronized (this) {

                    //NEW
                    //@author Stefano Omini
                    //the presence of this "if" allows pause control
                    if (blocked) {
                        try {
                            wait();
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    }
                    //end NEW

                

                    n++;

                    if (n % refreshPeriod == 0) {

                        //User may have defined measures that will not receive any sample
                        if (n % reachabilityTest == 0) {
                            //stop measures which haven't collected samples yet
                            NetSystem.stopNoSamplesMeasures();
                        }
                        //refresh measures
                        NetSystem.checkMeasures();
                    }

                }

			}
            //sim is finished: get stop time
			stopTime = NetSystem.getElapsedTime();
            SimSystem.runStop();
			running = false;

		} catch (Exception Exc) {
			Exc.printStackTrace();
		}
	}

	public void start() {
		running = true;
	}

	/** Checks if the NetSystem Engine thread is running.
	 * @return True if NetSystem Engine thread is running.
	 */
	synchronized boolean isRunning() {
		return running;
	}

	/** Gets simulation time.
	 * @return Simulation time.
	 */
	synchronized double getSimulationTime() {
		return stopTime - startTime;
	}

	/** Imposes that NetController should be stopped if a specific getLog level is
	 * reached.
	 * @param StopLevel Level which NetSystem should be stopped.
	 */
	synchronized void stopOnLogLevel(int StopLevel) {
		this.stopLevel = StopLevel;
	}

	/** Imposes that NetController should be aborted if a specific getLog level is
	 * reached.
	 * @param AbortLevel Level which NetSystem should be aborted.
	 */
	synchronized void abortOnLogLevel(int AbortLevel) {
		this.abortLevel = AbortLevel;
	}


    /**
     * Blocks NetController for synchronized access to data.
     */
    public synchronized void block() {
		blocked = true;
	}

	/**
     * Unblocks the object.
     */
    public synchronized void unblock() {
		blocked = false;
		notifyAll();
	}

}