getresponsemessage.java

High performance DB query

/*
 * @(#)$Id: GetResponseMessage.java,v 1.8 2004/07/02 23:59:20 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 overlay.provider.basic;

import services.network.Payload;
import util.BitID;
import util.FreeList;
import util.FreeListFactory;
import util.network.serialization.GenericByteBuffer;
import util.network.serialization.SerializationManager;
import util.network.serialization.SerializeBool;

/**
 * Class GetResponseMessage
 *
 */
public class GetResponseMessage extends ProviderMessage {

    public static long serialVersionUID =
        SerializationManager.getSerialUID(
            "overlay.provider.basic.GetResponseMessage");

    // the instance ID of the item
    private boolean result;

    // the actual item
    private Payload item;

    // free list of objects for better memory management
    private static FreeList freeList =
        new FreeList(new GetResponseMessageFactory());

    /**
     * DeSerialize the object from the provided GenericByteBuffer.
     *
     * @param inputBuffer
     */
    public GetResponseMessage(GenericByteBuffer inputBuffer) {
        super(inputBuffer);

        this.result = SerializeBool.deSerialize(inputBuffer);
        this.item = SerializationManager.deSerialize(inputBuffer);
        this.size += Payload.INT_SIZE;

        if (this.item != null) {
            this.size += SerializationManager.getPayloadSize(this.item);
        }
    }

    /**
     * Serialize the object into the provided GenericByteBuffer.
     *
     * @param outputBuffer
     * @return
     */
    public long serialize(GenericByteBuffer outputBuffer) {
        super.serialize(outputBuffer);
        SerializeBool.serialize(outputBuffer, result);
        SerializationManager.serialize(outputBuffer, item);

        return serialVersionUID;
    }

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

    private void init(Integer messageID, String ns, String rid,
                      BitID locationID, boolean result, Payload item) {
        super.init(messageID, ns, rid, locationID);

        this.result = result;
        this.item = item;

        // set the size
        size += Payload.INT_SIZE;

        if (item != null) {
            size += SerializationManager.getPayloadSize(item);
        }
    }

    /**
     * Method getResult
     * @return
     */
    public boolean getResult() {
        return result;
    }

    /**
     * Method getItem
     * @return
     */
    public Payload getItem() {
        return item;
    }

    /**
     * Method allocate
     *
     * @param messageID
     * @param ns
     * @param rid
     * @param locationID
     * @param result
     * @param item
     * @return
     */
    public static GetResponseMessage allocate(Integer messageID, String ns,
                                              String rid, BitID locationID,
                                              boolean result, Payload item) {
        GetResponseMessage message = (GetResponseMessage) freeList.allocate();

        message.init(messageID, ns, rid, locationID, result, item);

        return message;
    }

    /**
     * Method free
     *
     * @param message
     */
    public static void free(GetResponseMessage message) {
        freeList.free(message);
    }
}


/**
 * Class GetResponseMessageFactory
 *
 */
class GetResponseMessageFactory implements FreeListFactory {

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