routingpolicy.java

High performance DB query

/*
 * @(#)$Id: RoutingPolicy.java,v 1.5 2004/07/02 23:59:21 huebsch Exp $
 *
 * Copyright (c) 2001-2004 Regents of the University of California.
 * All rights reserved.
 *
 * This file is distributed under the terms in the attached BERKELEY-LICENSE
 * file. If you do not find these files, copies can be found by writing to:
 * Computer Science Division, Database Group, Universite of California,
 * 617 Soda Hall #1776, Berkeley, CA 94720-1776. Attention: Berkeley License
 *
 * Copyright (c) 2003-2004 Intel Corporation. All rights reserved.
 *
 * This file is distributed under the terms in the attached INTEL-LICENSE file.
 * If you do not find these files, copies can be found by writing to:
 * Intel Research Berkeley, 2150 Shattuck Avenue, Suite 1300,
 * Berkeley, CA, 94704.  Attention:  Intel License Inquiry.
 */


package pier.helpers.routingpolicy;

import java.util.HashMap;
import pier.data.Tuple;

/**
 * Class RoutingPolicy
 *
 * To allow many different routing policies
 */
public abstract class RoutingPolicy {

    // not sure what each routing policy will need, so give em both
    protected HashMap doneReadyMap;
    protected HashMap sourceInitMap;

    /**
     * Constructor RoutingPolicy
     *
     *
     * @param sourceInitMap
     * @param doneReadyMap
     */
    public RoutingPolicy(HashMap sourceInitMap, HashMap doneReadyMap) {
        this.doneReadyMap = doneReadyMap;
        this.sourceInitMap = sourceInitMap;
    }

    /**
     * Method getNextOperator
     *
     *
     * Based on the metadata in the tuple (ready, done bits), find
     * the next operator (based on operator position) to route to
     * according to the routing policy
     *
     * @param item the tuple to determine the next op for
     * @return the operator position to route to
     */
    public abstract int getNextOperator(Tuple item);
}