Partitioner.java

/**
 *  Copyright 2007-2008 University Of Southern California
 *
 *  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 edu.isi.pegasus.planner.partitioner;


import edu.isi.pegasus.common.logging.LogManagerFactory;
import edu.isi.pegasus.planner.common.PegasusProperties;
import edu.isi.pegasus.common.logging.LogManager;

import edu.isi.pegasus.planner.partitioner.graph.GraphNode;

import java.util.Map;

/**
 * The abstract class that lays out the api to do the partitioning of the dax
 * into smaller daxes. It defines additional functions to get and set the name
 * of the partitions etc.
 *
 * @author Karan Vahi
 * @version $Revision$
 */

public abstract class Partitioner {

    /**
     * The package name where the implementing classes of this interface reside.
     */
    public static final String PACKAGE_NAME = "org.griphyn.cPlanner.partitioner";

    /**
     * The version number associated with this API of Code Generator.
     */
    public static final String VERSION = "1.2";


    /**
     * The root node of the graph from where to start the BFS.
     */
    protected GraphNode mRoot;

    /**
     * The map containing all the graph nodes. The key to the map are the logical
     * id's of the jobs as identified in the dax and the values are the
     * corresponding Graph Node objects.
     */
    protected Map mGraph;



    /**
     * The handle to the internal logging object.
     */
    protected LogManager mLogger;

    /**
     * The object holding all the properties pertaining to Pegasus.
     */
    protected PegasusProperties mProps;


    /**
     * The overloaded constructor.
     *
     * @param root       the dummy root node of the graph.
     * @param graph      the map containing all the nodes of the graph keyed by
     *                   the logical id of the nodes.
     * @param properties the properties passed out to the planner.
     */
    public Partitioner(GraphNode root, Map graph, PegasusProperties properties) {
        mRoot  = root;
        mGraph = graph;
        mLogger = LogManagerFactory.loadSingletonInstance( properties );
        mProps = properties;
        //set a default name to the partition dax
        //mPDAXWriter = null;

    }

    /**
     * The main function that ends up traversing the graph structure corrsponding
     * to the dax and creates the smaller dax files(one dax file per partition)
     * and the .pdax file that illustrates the partition graph. It is recommended
     * that the implementing classes use the already initialized handles to the
     * DAXWriter and PDAXWriter interfaces to write out the xml files. The
     * advantage of using these preinitialized handles is that they already
     * are correctly configured for the directories where Pegasus expects the
     * submit files and dax files to reside.
     *
     *
     * @param c  the callback object that the partitioner calls out to.
     */
    public abstract void determinePartitions( Callback c );



    /**
     * Returns a textual description of the transfer implementation.
     *
     * @return a short textual description
     */
    public abstract String description();



}