org/objectweb/proactive/calcium/Facade.java

/* 
 * ################################################################
 * 
 * ProActive: The Java(TM) library for Parallel, Distributed, 
 *            Concurrent computing with Security and Mobility
 * 
 * Copyright (C) 1997-2007 INRIA/University of Nice-Sophia Antipolis
 * Contact: proactive@objectweb.org
 * 
 * This library 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 any later version.
 *  
 * This library 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 library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
 * USA
 *  
 *  Initial developer(s):               The ProActive Team
 *                        http://www.inria.fr/oasis/ProActive/contacts.html
 *  Contributor(s): 
 * 
 * ################################################################
 */ 
package org.objectweb.proactive.calcium;

import java.io.Serializable;
import java.util.Hashtable;
import java.util.Vector;

import org.objectweb.proactive.ProActive;
import org.objectweb.proactive.calcium.Skernel;
import org.objectweb.proactive.calcium.exceptions.PanicException;

public class Facade {

        private Skernel skernel;
        private TaskStreamQueue results;
        
        public Facade(Skernel skernel){
                this.skernel=skernel;
                this.results = new TaskStreamQueue();
        }
        
        public synchronized void putTask(Task<?> task){ 
                skernel.putTask(task);
        }
        
        public void boot(Skernel skernel){
                this.skernel=skernel;
        }
        
        @SuppressWarnings("unchecked")
        public synchronized <T> Task<T> getResult(int streamId) throws PanicException{
                        
                //Get new tasks from the skernel
                try {
                        while(results.isEmpty(streamId)){
                                wait(1000);
                                loadResultsFromSkernel();
                        }
                } catch (InterruptedException e) {               
                        e.printStackTrace();
                        return null;
                }
                
                return (Task<T>)results.get(streamId);
        }
        
        private synchronized void loadResultsFromSkernel() throws PanicException{
                while(skernel.hasResults()){
                        Task<?> taskResult =  (Task<?>) skernel.getResult();

                        //TODO Temporary ProActive generics bug workaround 
                        //This is the supelec trick
                        taskResult=(Task<?>)ProActive.getFutureValue(taskResult);
                        results.put(taskResult);
                }
        }

        class TaskStreamQueue implements Serializable{
                
                Hashtable<Integer, Vector<Task<?>>> results;
                int size;
                
                public TaskStreamQueue(){
                        results = new Hashtable<Integer, Vector<Task<?>>>();
                        size=0;
                }
                
                public synchronized void put(Task<?> task){
                        int streamId=task.getStreamId();

                        if(!results.containsKey(streamId)){
                                results.put(streamId, new Vector<Task<?>>());
                        }
                        
                        Vector<Task<?>> vector=results.get(streamId);
                        
                        vector.add(task);
                        size++;
                }
                
                public synchronized Task<?> get(int streamId){
                        if(isEmpty(streamId)) return null;
                         
                        Vector<Task<?>> vector=results.get(streamId);
                        if(vector.size()==0) return null;
                        if(vector.size()==1) results.remove(streamId);
                        size--;
                        return vector.remove(0);
                }
                
                public synchronized boolean isEmpty(int streamId){
                        return !results.containsKey(streamId);
                }
                
                public synchronized int size(){
                        return size;
                }
                
                public synchronized int size(int streamId){
                        if(isEmpty(streamId)) return 0;
                        Vector<Task<?>> vector=results.get(streamId);
                        return vector.size();
                }
        }
}

---