RepSim.java

/*
 * Class:        RepSim
 * Description:  simulation using independent runs or replications
 * Environment:  Java
 * Software:     SSJ 
 * Copyright (C) 2001  Pierre L'Ecuyer and Universite de Montreal
 * Organization: DIRO, Universite de Montreal
 * @author       Éric Buist
 * @since        2007
 
 * SSJ is free software: you can redistribute it and/or modify it under
 * the terms of the GNU General Public License (GPL) as published by the
 * Free Software Foundation, either version 3 of the License, or
 * any later version.
 
 * SSJ 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.
 
 * A copy of the GNU General Public License is available at
   <a href="http://www.gnu.org/licenses">GPL licence site</a>.
 */
package umontreal.ssj.simexp;
 
import umontreal.ssj.simevents.Simulator;

public abstract class RepSim extends SimExp {
   private int minReps;
   private int maxReps;
   private int targetReps;
   private int doneReps;

   public RepSim(int minReps) {
      this(minReps, Integer.MAX_VALUE);
   }

   public RepSim(int minReps, int maxReps) {
      this(Simulator.getDefaultSimulator(), minReps, maxReps);
   }

   public RepSim(Simulator sim, int minReps) {
      this(sim, minReps, Integer.MAX_VALUE);
   }

   public RepSim(Simulator sim, int minReps, int maxReps) {
      super(sim);
      if (minReps <= 0)
         throw new IllegalArgumentException("minReps <= 0");
      if (minReps > maxReps)
         throw new IllegalArgumentException("minReps > maxReps");
      this.minReps = minReps;
      this.maxReps = maxReps;
      targetReps = minReps;
   }

   public int getMinReplications() {
      return minReps;
   }

   public void setMinReplications(int minReps) {
      if (minReps <= 0)
         throw new IllegalArgumentException("minReps <= 0");
      this.minReps = minReps;
      if (maxReps < minReps)
         maxReps = minReps;
   }

   public int getMaxReplications() {
      return maxReps;
   }

   public void setMaxReplications(int maxReps) {
      if (maxReps < minReps)
         throw new IllegalArgumentException("maxReps < minReps");
      this.maxReps = maxReps;
   }

   public int getTargetReplications() {
      return targetReps;
   }

   public void setTargetReplications(int targetReps) {
      if (targetReps < minReps)
         throw new IllegalArgumentException("Target number of replications too small");
      if (targetReps > maxReps)
         throw new IllegalArgumentException("Target number of replications too large");
      this.targetReps = targetReps;
   }

   public int getCompletedReplications() {
      return doneReps;
   }

   public abstract void initReplicationProbes();

   public void performReplication(int r) {
      simulator().init();
      initReplication(r);
      simulator().start();
      replicationDone();
      addReplicationObs(r);
   }

   protected void replicationDone() {
      ++doneReps;
   }

   public abstract void initReplication(int r);

   public abstract void addReplicationObs(int r);

   public int getRequiredNewReplications() {
      return 0;
   }

   public void init() {
      if (simulating)
         throw new IllegalStateException("Already simulating");
      doneReps = 0;
      if (targetReps < minReps)
         // minReps has been increased, so increase targetReps too
         targetReps = minReps;
      initReplicationProbes();
   }

   public void adjustTargetReplications(int numNewReplications) {
      if (numNewReplications < 0)
         throw new IllegalArgumentException("numReplications < 0");
      if (numNewReplications == 0)
         return;
      targetReps = doneReps + numNewReplications;
      if (targetReps > maxReps)
         targetReps = maxReps;
   }

   public void simulate() {
      init();
      simulating = true;
      try {
         while (doneReps < targetReps) {
            for (int i = 0; i < targetReps; i++)
               performReplication(i);
            adjustTargetReplications(getRequiredNewReplications());
         }
      } finally {
         simulating = false;
      }
   }
 
   public String toString() {
      StringBuffer sb = new StringBuffer(getClass().getName());
      sb.append('[');
      sb.append("minimal number of replications: ").append(minReps);
      if (maxReps < Integer.MAX_VALUE)
         sb.append(", maximal number of replications: ").append(maxReps);
      sb.append(", target number of replications: ").append(targetReps);
      if (simulating)
         sb.append(", simulation in progress");
      else
         sb.append(", simulation stopped");
      sb.append(", number of completed replications: ").append(doneReps);
      sb.append(']');
      return sb.toString();
   }
}