actualtimerevent.java

High performance DB query

/*
 * @(#)$Id: ActualTimerEvent.java,v 1.3 2004/07/02 23:59:22 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 runtime.services.timer;

import services.timer.TimerClient;
import util.FreeList;
import util.FreeListFactory;

/**
 * Class ActualTimerEvent
 *
 */
public class ActualTimerEvent implements Comparable {

    private double executionTime;
    private Object data;
    private TimerClient client;
    private long id;
    private static long counter;
    private static FreeList freeList =
        new FreeList(new ActualTimerEventFactory());

    /**
     * Constructor ActualTimerEvent
     */
    protected ActualTimerEvent() {}

    /**
     * Method init
     *
     * @param executionTime
     * @param data
     * @param client
     */
    public void init(double executionTime, Object data, TimerClient client) {
        this.executionTime = executionTime;
        this.data = data;
        this.client = client;
        this.id = counter++;
    }

    /**
     * Method getExecutionTime
     * @return
     */
    public double getExecutionTime() {
        return executionTime;
    }

    /**
     * Method getData
     * @return
     */
    public Object getData() {
        return data;
    }

    /**
     * Method getClient
     * @return
     */
    public TimerClient getClient() {
        return client;
    }

    /**
     * Method compareTo
     *
     * @param other
     * @return
     */
    public int compareTo(Object other) {
        ActualTimerEvent otherEvent = (ActualTimerEvent) other;

        if (executionTime < otherEvent.executionTime) {
            return -1;
        }

        if (executionTime > otherEvent.executionTime) {
            return 1;
        }

        if (id < otherEvent.id) {
            return -1;
        }

        if (id > otherEvent.id) {
            return 1;
        }

        return 0;
    }

    /**
     * Method equals
     *
     * @param other
     * @return
     */
    public boolean equals(Object other) {
        ActualTimerEvent otherEvent = (ActualTimerEvent) other;

        return (id == otherEvent.id);
    }

    /**
     * Method toString
     * @return
     */
    public String toString() {
        return "<TIMEEVENT: TIME:" + executionTime + ", ID:" + id + ", Client:"
               + client + ", Data:" + data + ">";
    }

    /**
     * Method allocate
     *
     * @param executionTime
     * @param data
     * @param client
     * @return
     */
    public static ActualTimerEvent allocate(double executionTime, Object data,
                                            TimerClient client) {
        ActualTimerEvent event;

        synchronized (freeList) {
            event = (ActualTimerEvent) freeList.allocate();
        }

        event.init(executionTime, data, client);

        return event;
    }

    /**
     * Method free
     *
     * @param event
     */
    public static void free(ActualTimerEvent event) {
        synchronized (freeList) {
            freeList.free(event);
        }
    }
}


/**
 * Class ActualTimerEventFactory
 *
 */
class ActualTimerEventFactory implements FreeListFactory {

    /**
     * Method create
     * @return
     */
    public Object create() {
        return new ActualTimerEvent();
    }
}