package umontreal.iro.lecuyer.rng;

import umontreal.iro.lecuyer.rng.RandomStream;
import umontreal.iro.lecuyer.rng.MRG32k3a;


/**
 * Represents a random stream factory capable
 * of constructing instances of a given type of random stream
 * by invoking the {@link #newInstance(()) newInstance} method
 * each time a new random stream is needed, instead of invoking
 * directly the specific constructor of the desired type.
 * Hence, if several random streams of a given type (class) must be
 * constructed at different places in a large simulation program,
 * and if we decide to change the type of stream in the future,
 * there is no need to change the code at those different places.
 * With the random stream factory, the class-specific
 * code for constructing these streams appears at a single place,
 * where the factory is constructed.
 * 
 * 

 * The class {@link BasicRandomStreamFactory} provides an 
 * implementation of this interface.
 * 
 */
public interface RandomStreamFactory {


   /**
    * Constructs and returns a new random stream.
    *  If the instantiation of the random stream fails,
    *  this method throws a {@link RandomStreamInstantiationException}.
    * 
    * @return the newly-constructed random stream.
    *    @exception RandomStreamInstantiationException if the new
    *     random stream cannot be instantiated.
    * 
    */
   public RandomStream newInstance();

}