topic.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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"FreePastry" Peer-to-Peer Application Development Substrate

Copyright 2002, Rice University. All rights reserved.

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package planet.scribe;

import java.io.*;

import planet.commonapi.*;
import planet.commonapi.factory.*;
import planet.commonapi.exception.InitializationException;

/**
 * This interface represents a specific topic in the Scribe system.
 *
 * @version $Id: Topic.java,v 1.1 2003/09/24 02:20:07 amislove Exp $
 * @author Alan Mislove
 */
public class Topic implements Serializable {

  /**
   * The Id to which this topic is mapped
   */
  protected Id id;

  /**
   * Constructor which takes an Id for this topic
   *
   * @param id The Id for this topic
   */
  public Topic(Id id) {
    this.id = id;
  }

  /**
   * Constructor which takes a name for this topic
   *
   * @param factory The factory to use when creating the id
   * @param name The name for this topic
   */
  public Topic(IdFactory factory, String name) throws InitializationException {
    this.id = getId(factory, name);
  }

  /**
   * Returns the Id to which this topic is mapped
   *
   * @return The id to which this topic is mapped
   */
  public Id getId() {
    return id;
  }

  /**
   * Returns the Id to which the string is mapped
   *
   * @param factory The factory to use when creating the id
   * @param name The string to map
   * @return The id to which this string is mapped
   */
  public static Id getId(IdFactory factory, String name) throws InitializationException {
    return factory.buildId(name);
  }

  /**
   * Returns whether this is equal to o or not
   *
   * @param o The object to compare to
   * @return Whether or not they are equal
   */
  public boolean equals(Object o) {
    if (o instanceof Topic) {
      return ((Topic) o).id.equals(id);
    }

    return false;
  }

  /**
   * Returns the hashCode for this topic
   *
   * @return The hashcode for this topic
   */
  public int hashCode() {
    return id.hashCode();
  }

  /**
   * Returns a String representation of this topic
   *
   * @return A String representation of this topic
   */
  public String toString() {
    return "[TOPIC " + id + "]";
  }
  
}