scribe.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

/*************************************************************************

"FreePastry" Peer-to-Peer Application Development Substrate

Copyright 2002, Rice University. All rights reserved.

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- Redistributions in binary form must reproduce the above copyright
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********************************************************************************/

package planet.scribe;

import planet.commonapi.*;

/**
 * This interface is exported by all instances of Scribe.  
 *
 * @version $Id: Scribe.java,v 1.5 2003/10/22 03:16:39 amislove Exp $
 * @author Alan Mislove
 */
public interface Scribe {

  /**
   * Subscribes the given client to the provided topic.  Any message published
   * to the topic will be delivered to the Client via the deliver() method.
   *
   * @param topic The topic to subscribe to
   * @param client The client to give messages to
   */
  public void subscribe(Topic topic, ScribeClient client);

  /**
   * Subscribes the given client to the provided topic.  Any message published
   * to the topic will be delivered to the Client via the deliver() method.
   *
   * @param topic The topic to subscribe to
   * @param client The client to give messages to
   * @param content The content to include in the subscribe
   */
  public void subscribe(Topic topic, ScribeClient client, ScribeContent content);

  /**
   * Unsubscribes the given client from the provided topic. 
   *
   * @param topic The topic to unsubscribe from
   * @param client The client to unsubscribe
   */
  public void unsubscribe(Topic topic, ScribeClient client);

  /**
   * Publishes the given message to the topic.
   *
   * @param topic The topic to publish to
   * @param content The content to publish
   */
  public void publish(Topic topic, ScribeContent content);

  /**
   * Anycasts the given content to a member of the given topic
   *
   * @param topic The topic to anycast to
   * @param content The content to anycast
   */
  public void anycast(Topic topic, ScribeContent content);

  /**
   * Returns the current policy for this scribe object
   *
   * @return The current policy for this scribe
   */
  public ScribePolicy getPolicy();

  /**
   * Sets the current policy for this scribe object
   *
   * @param policy The current policy for this scribe
   */
  public void setPolicy(ScribePolicy policy);

  /**
   * Returns whether or not this Scribe is the root for the given topic
   *
   * @param topic The topic in question
   * @return Whether or not we are currently the root
   */
  public boolean isRoot(Topic topic);

  /**
   * Returns the list of children for a given topic
   *
   * @param topic The topic to return the children of
   * @return The children of the topic
   */
  public NodeHandle[] getChildren(Topic topic);

  /**
   * Adds a child to the given topic
   *
   * @param topic The topic to add the child to
   * @param child The child to add
   */
  public void addChild(Topic topic, NodeHandle child);

  /**
   * Removes a child from the given topic
   *
   * @param topic The topic to remove the child from
   * @param child The child to remove
   */
  public void removeChild(Topic topic, NodeHandle child);
}