Beispiel #1
0
  /**
   * This method is the main function of the thread of the collective. It does housekeeping and
   * regularly talks to peers to exchange information. It can be stopped by calling <code>close()
   * </code>.
   *
   * @see #close()
   */
  public final void run() {

    while (shouldLive) {
      // try{
      System.gc();
      removeOldStuff();
      if (!refresh()) {
        Address[] a = observer.getPeerAddresses();
        if (a != null)
          synchronized (cache) {
            for (int i = 0; i < a.length; ++i)
              cache.put(a[i].name, new ContributionBox(a[i], null));
          }
      }
      for (int i = 0; i < REFRESHRATE; i += 1000) {
        try {
          Thread.sleep(1000);
        } catch (InterruptedException e) {
          shouldLive = false;
        }
        if (shouldLive == false) break;
        Thread.yield();
      }
      /*}
      catch( RuntimeException e )
      {
      	Logger.error( "Collective#run()",
      	"Runtime exception caught, something is going wrong",e);

      }*/
    }

    cache = null;
    observer = null;
  }
Beispiel #2
0
  /**
   * Handles a message. Knows type "collectiveUpdate-"+name only. It is the responsibility of the
   * owner to propagate messages of this type using this method.
   */
  public boolean handleMessage(Message m, Object o) {

    if (!shouldLive || !m.getType().equals("collectiveUpdate-" + name)) return false;

    final String logSender = observer + "#collectiveUpdate";

    Logger.debug(logSender, "Update from " + m.getSender());

    /**/
    if (!m.getRecipient().name.equals(contributor.getName()))
      Logger.warning(
          logSender,
          "Recipient and my contributor are not the same:\n"
              + "Recipient: "
              + m.getRecipient().name
              + "\n"
              + "Contributor: "
              + contributor.getName(),
          null);
    /**/

    Collective c = (Collective) o;

    // --- reset array representations
    cacheCollection = null;
    commandCollection = null;

    // --- remove possible garbage
    cache.remove(m.getRecipient().name);
    c.cache.remove(m.getRecipient().name);
    cache.remove(m.getSender().name);
    c.cache.remove(m.getSender().name);

    // --- sending our contributions
    if (contributor == null)
      Logger.warning(logSender, "Non-contributor observer is known by " + m.getSender(), null);
    updateLocalInfo();
    m.setReply(this);

    // --- update containers
    repairSenderAddress(c, m.getSender());
    merge(c);
    observer.collectiveUpdated((ContributionBox) cache.get(m.getSender().name));

    return true;
  }
Beispiel #3
0
  /**
   * Initiates an information exchange with a known and living other base if such a base exists.
   *
   * @return true if refresh was succesful, false otherwise.
   */
  private boolean refresh() {

    final String logSender = observer + "#refresh";
    final String contrName = ((contributor != null) ? contributor.getName() : null);

    // --- refreshing local contribution and commands
    updateLocalInfo();

    // --- creating a random permutation of peers
    Vector peers = null;
    synchronized (cache) {
      peers = new Vector(cache.values());
      // just to be sure, shouldn't be there anyway
      if (contrName != null) peers.remove(cache.get(contrName));
    }
    Collections.shuffle(peers);
    if (peers.isEmpty()) {
      Logger.debug(logSender, "no peers in cache");
      return false;
    }

    // --- reset array representations
    cacheCollection = null;
    commandCollection = null;

    // --- trying to talk to random peer
    IRequest answer = null;
    Address peer = null;
    for (int i = 0; i < peers.size(); ++i) {
      if (!shouldLive) return false;

      peer = ((ContributionBox) peers.get(i)).contributor;
      Logger.debug(logSender, "asking " + peer);

      answer = observer.fireMessage(peer, "collectiveUpdate-" + name, this);
      while (answer.getStatus() == IRequest.WAITING) {
        try {
          Thread.sleep(100);
        } catch (Exception e) {
        }
      }
      if (answer.getStatus() == IRequest.DONE) break;
      Logger.debug(logSender, "not accessable: " + peer);
    }

    if (answer.getStatus() != IRequest.DONE) {
      Logger.debug(logSender, "no accessable peers");
      observer.collectiveUpdated(null);
      return false;
    } else {
      Collective c = (Collective) answer.getInfo("reply");

      // --- remove possible garbage
      if (contributor != null) {
        cache.remove(contributor.getName());
        c.cache.remove(contributor.getName());
      }
      cache.remove(peer.name);
      c.cache.remove(peer.name);

      repairSenderAddress(c, peer);
      merge(c);
      observer.collectiveUpdated((ContributionBox) cache.get(c.myContribution.contributor.name));
      return true;
    }
  }