subscribemessage.java

p2p仿真器。开发者可以工作在覆盖层中进行创造和测试逻辑算法或者创建和测试新的服务。PlanetSim还可以将仿真代码平稳转换为在Internet上的实验代码

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"Free Pastry" Peer-to-Peer Application Development Substrate

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package planet.scribe.messaging;

import planet.commonapi.*;
import planet.scribe.*;

/**
 * @version $Id: SubscribeMessage.java,v 1.6 2003/10/22 03:16:43 amislove Exp $
 * @author Alan Mislove
 */
public class SubscribeMessage extends AnycastMessage {

  /**
   * The original subscriber
   */
  protected NodeHandle subscriber;

  /**
   * The previous parent
   */
  protected Id previousParent;

  /**
   * The id of this message
   */
  protected int id;

  /**
   * @param source The source address
   * @param topic The topic
   * @param id The UID for this message
   * @param content The content
   */
  public SubscribeMessage(NodeHandle source, Topic topic, int id, ScribeContent content) {
    this(source, topic, null, id, content);
  }

  /**
   * Constructor which takes a unique integer Id
   *
   * @param source The source address
   * @param topic The topic
   * @param id The UID for this message
   * @param content The content
   * @param previousParent The parent on this topic who died
   */
  public SubscribeMessage(NodeHandle source, Topic topic, Id previousParent, int id, ScribeContent content) {
    super(source, topic, content);

    this.id = id;
    this.subscriber = source;
    this.previousParent = previousParent;
  }

  /**
   * Returns the node who is trying to subscribe
   *
   * @return The node who is attempting to subscribe
   */
  public NodeHandle getSubscriber() {
    return subscriber;
  }

  /**
   * Returns the node who is trying to subscribe
   *
   * @return The node who is attempting to subscribe
   */
  public Id getPreviousParent() {
    return previousParent;
  }

  /**
   * Returns this subscribe lost message's id
   *
   * @return The id of this subscribe lost message
   */
  public int getId() {
    return id;
  }

  /**
   * Returns a String represneting this message
   *
   * @return A String of this message
   */
  public String toString() {
    return "[SubscribeMessage " + topic + " subscriber " + subscriber.getId() + "]";
  }

}