BasicRandomStreamFactory.java

/*
 * Class:        BasicRandomStreamFactory
 * Description:  basic random stream factory
 * Environment:  Java
 * Software:     SSJ 
 * Copyright (C) 2001  Pierre L'Ecuyer and Universite de Montreal
 * Organization: DIRO, Universite de Montreal
 * @author       
 * @since
 *
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 */
package umontreal.ssj.rng;
 
import umontreal.ssj.rng.RandomStream;
import umontreal.ssj.rng.MRG32k3a;

public class BasicRandomStreamFactory implements RandomStreamFactory {
   private Class rsClass;

   public BasicRandomStreamFactory(Class rsClass) {
      checkRandomStreamClass(rsClass);
      this.rsClass = rsClass;
   }

   public Class getRandomStreamClass() {
      return rsClass;
   }

   public void setRandomStreamClass(Class rsClass) {
      checkRandomStreamClass(rsClass);
      this.rsClass = rsClass;
   }
 
   private void checkRandomStreamClass(final Class rsClass) {
      if (!RandomStream.class.isAssignableFrom(rsClass))
         throw new IllegalArgumentException("The random class must implement the RandomStream interface");
      try {
         rsClass.getConstructor(new Class[0]);
      } catch (NoSuchMethodException nme) {
         throw new IllegalArgumentException(
               "The random stream class " + rsClass.getName() + " does not have a " + "nullary public constructor.");
      }
   }
 
   public RandomStream newInstance() {
      try {
         return (RandomStream) rsClass.newInstance();
      } catch (IllegalAccessException iae) {
         throw new RandomStreamInstantiationException(this,
               "Cannot access constructor for random stream class " + rsClass.getName(), iae);
      } catch (InstantiationException ie) {
         throw new RandomStreamInstantiationException(this,
               "Cannot instantiate random stream class " + rsClass.getName(), ie);
      } catch (Exception e) {
         throw new RandomStreamInstantiationException(this,
               "Exception while calling the nullary constructor for random stream class " + rsClass.getName(), e);
      }
   }
 
   public String toString() {
      return "Basic random stream factory constructing streams of class " + rsClass.getName();
   }
}