/*
* JBoss, Home of Professional Open Source.
* Copyright 2008, Red Hat Middleware LLC, and individual contributors
* as indicated by the @author tags. See the copyright.txt file in the
* distribution for a full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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 software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.ha.framework.interfaces;
import java.util.List;
import java.util.Random;
import org.jboss.invocation.Invocation;
/**
* LoadBalancingPolicy implementation that always fully randomly select its target
* (without basing its decision on any historic).
*
* @author <a href="mailto:sacha.labourey@cogito-info.ch">Sacha Labourey</a>.
* @version $Revision: 81001 $
* @see org.jboss.ha.framework.interfaces.LoadBalancePolicy
*/
public class RandomRobin implements LoadBalancePolicy
{
// Constants -----------------------------------------------------
/** @since 1.1.2.3 */
private static final long serialVersionUID = -3599638697906618428L;
/** This needs to be a class variable or else you end up with multiple
* Random numbers with the same seed when many clients lookup a proxy.
*/
public static final Random localRandomizer = new Random (System.currentTimeMillis ());
// Static --------------------------------------------------------
// Constructors --------------------------------------------------
// Public --------------------------------------------------------
// LoadBalancePolicy implementation ----------------------------------------------
public void init (HARMIClient father)
{
// do not use the HARMIClient in this policy
}
public Object chooseTarget (FamilyClusterInfo clusterFamily)
{
return chooseTarget(clusterFamily, null);
}
public Object chooseTarget (FamilyClusterInfo clusterFamily, Invocation routingDecision)
{
List targets = clusterFamily.getTargets ();
int max = targets.size();
if (max == 0)
return null;
int cursor = localRandomizer.nextInt (max);
return targets.get(cursor);
}
}