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/** Notice of modification as required by the LGPL
 *  This file was modified by Gemstone Systems Inc. on
 *  $Date$
 **/
// $Id: ClientGmsImpl.java,v 1.29 2005/11/22 11:58:28 belaban Exp $

package com.gemstone.org.jgroups.protocols.pbcast;



import com.gemstone.org.jgroups.Address;
import com.gemstone.org.jgroups.Event;
import com.gemstone.org.jgroups.Message;
import com.gemstone.org.jgroups.ShunnedAddressException;
import com.gemstone.org.jgroups.View;
import com.gemstone.org.jgroups.ViewId;
import com.gemstone.org.jgroups.protocols.PingRsp;
import com.gemstone.org.jgroups.protocols.UNICAST;
import com.gemstone.org.jgroups.protocols.UNICAST.UnicastHeader;
import com.gemstone.org.jgroups.stack.IpAddress;
import com.gemstone.org.jgroups.util.ExternalStrings;
import com.gemstone.org.jgroups.util.Promise;
import com.gemstone.org.jgroups.util.Util;

import java.net.Inet6Address;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.List;
import java.util.Set;
import java.util.TreeSet;
import java.util.Vector;


/**
 * Client part of GMS. Whenever a new member wants to join a group, it starts in the CLIENT role.
 * No multicasts to the group will be received and processed until the member has been joined and
 * turned into a SERVER (either coordinator or participant, mostly just participant). This class
 * only implements Join (called by clients who want to join a certain group, and
 * ViewChange which is called by the coordinator that was contacted by this client, to
 * tell the client what its initial membership is.
 * @author Bela Ban
 * @version $Revision: 1.29 $
 */
public class ClientGmsImpl extends GmsImpl  {
    public static volatile boolean SLOW_JOIN; // test hook for bug #49897
    public static volatile Object SLOW_JOIN_LOCK;
    
    private final Vector  initial_mbrs=new Vector(11);
    private volatile/*GemStoneAddition*/ boolean       initial_mbrs_received=false; // GemStoneAddition - accesses synchronized on initial_mbrs
    private final Promise join_promise=new Promise();

    private volatile JoinRsp getViewResponse; // GemStoneAddition - when becoming coord of existing group
    private volatile int getViewResponses;
    private final Object getViewLock = new Object();
    private Set missing_mbrs = null;
    
    private int findInitialMbrsAttempts = 0;


    public ClientGmsImpl(GMS g) {
        super(g);
    }

    @Override // GemStoneAddition
    public void init() throws Exception {
        super.init();
        synchronized(initial_mbrs) {
            initial_mbrs.clear();
            initial_mbrs_received=false;
        }
        join_promise.reset();
    }


    /**
     * Joins this process to a group. Determines the coordinator and sends a unicast
     * handleJoin() message to it. The coordinator returns a JoinRsp and then broadcasts the new view, which
     * contains a message digest and the current membership (including the joiner). The joiner is then
     * supposed to install the new view and the digest and starts accepting mcast messages. Previous
     * mcast messages were discarded (this is done in PBCAST).

* If successful, impl is changed to an instance of ParticipantGmsImpl. * Otherwise, we continue trying to send join() messages to the coordinator, * until we succeed (or there is no member in the group. In this case, we create our own singleton group). *

When GMS.disable_initial_coord is set to true, then we won't become coordinator on receiving an initial * membership of 0, but instead will retry (forever) until we get an initial membership of > 0. * @param myAddr Our own address (assigned through SET_LOCAL_ADDRESS) */ @Override // GemStoneAddition public boolean join(Address myAddr) { Address coord = null; Address coordSentJoin = null; JoinRsp rsp; Digest tmp_digest; View tmp_view = null; leaving=false; long starttime = System.currentTimeMillis(); // GemStoneAddition final int maxRetries = 6; // GemStoneAddition - need this figure later int joinRetries = maxRetries; join_promise.reset(); boolean debugFailFirst = Boolean.getBoolean("p2p.DEBUG_FAIL_FIRST"); while(!leaving) { joinRetries--; if (joinRetries < 0) { // GemStoneAddition // if not just anyone can be the coordinator and the elected \ // coordinator cannot process a join_req, assume it is // gone and elect self as new coordinator if (coord != null && gms.floatingCoordinatorDisabled && !gms.splitBrainDetectionEnabled // bug #41772 I DON'T THINK THIS IS TRUE WITH QUORUM && myAddr.preferredForCoordinator()) { Address failedCoord = coord; if (!myAddr.equals(failedCoord)) { gms.log.getLogWriter().warning( ExternalStrings.ClientGmsImpl_COULD_NOT_JOIN_DISTRIBUTED_SYSTEM_0, failedCoord); if (becomeGroupCoordinator(myAddr, failedCoord)) { return true; } } coord = null; } else { if (!join_promise.hasResult()) { // GemStoneAddition - check one more time since we just waited for the retry log.warn("Could not join distributed system using member " + coord + ". gms.floatingCoordinatorDisabled="+gms.floatingCoordinatorDisabled + ", mbr.canBeCoordinator()=" + myAddr.preferredForCoordinator()); return false; } } } //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "findInitialMembers"); missing_mbrs = null; findInitialMembers(); //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "findInitialMembers done"); if (debugFailFirst) { log.getLogWriter().severe(ExternalStrings.ClientGmsImpl_IGNORING_FIRST_MEMBERSHIP_SET_FOR_DEBUGGING); debugFailFirst = false; continue; } if (!join_promise.hasResult()) { if(log.isDebugEnabled()) log.debug("CGMS: initial_mbrs are " + initial_mbrs + "; missing_mbrs are " + missing_mbrs); if(initial_mbrs.size() == 0) { if (missing_mbrs == null || missing_mbrs.isEmpty()) { // GemStoneAddition if(gms.disable_initial_coord) { // GemStoneAddition - there was no timeout if disable_ic was set!! checkForTimeout(starttime); //if(trace) log.warn("received an initial membership of 0, but cannot become coordinator " + // GemStoneAddition - was trace level output. Debug #34274 "(disable_initial_coord=true), will retry fetching the initial membership"); // continue; } // if we're getting no responses at all after two or more attempts, there's no-one // out there. else if (joinRetries <= (maxRetries - 2)) { if(log.isDebugEnabled()) log.debug("no initial members discovered: creating group as first member"); becomeSingletonMember(myAddr); return true; } } if (joinRetries > 0) { try { // GemStoneAddition //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "join sleep #1"); Util.sleep(gms.join_retry_timeout); //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "join sleep #1 done"); } catch (InterruptedException e) { if(log.isDebugEnabled()) log.debug("interrupted; creating group as first member"); becomeSingletonMember(myAddr); Thread.currentThread().interrupt(); // GemStoneAddition return true; } } continue; } //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "determining coordinator"); coord=determineCoord(initial_mbrs); //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "done determining coordinator: " + coord); // GemStoneAddition - don't elect a new coordinator on the first attempt if(coord == null) { if (joinRetries < maxRetries-1) { if(gms.handle_concurrent_startup == false) { if(trace) log.trace("handle_concurrent_startup is false; ignoring responses of initial clients"); becomeSingletonMember(myAddr); return true; } if(trace) log.trace("could not determine coordinator from responses " + initial_mbrs); // the member to become singleton member (and thus coord) is the first of all clients Set clients=new TreeSet(); // sorted clients.add(myAddr); // add myself again (was removed by findInitialMembers()) for(int i=0; i < initial_mbrs.size(); i++) { PingRsp pingRsp=(PingRsp)initial_mbrs.elementAt(i); Address client_addr=pingRsp.getCoordAddress(); // GemStoneAddition - was .getAddress(); if(client_addr != null) clients.add(client_addr); } if(trace) log.trace("Choosing coordinator from these servers: " + clients + ".\nJoin retries remaining: " + joinRetries); Address new_coord=(Address)clients.iterator().next(); if (new_coord.equals(myAddr)) { if (!gms.disable_initial_coord) { // GemStoneAddition - respect disable_initial_coord if(trace) log.trace("I (" + myAddr + ") am the first of the clients, and will become coordinator"); becomeSingletonMember(myAddr); // GemStoneAddition - tell the DM to wait a while //if (gms.stack.jgmm != null) { // long waitPeriod = Long.getLong("p2p.concStartupDelay", gms.join_timeout).longValue(); // if (trace) // log.trace("Telling the manager to wait for " + waitPeriod + " ms"); // gms.stack.jgmm.establishChannelPause(waitPeriod); // //try { Thread.sleep(waitPeriod); } catch (InterruptedException ie) { Thread.currentThread().interrupt(); } //} return true; } } else { // if(trace) // log.trace("I (" + myAddr + ") am not the first of the clients, " + // "waiting for another client to become coordinator"); log.getLogWriter() .info(ExternalStrings.DEBUG, "Waiting for " + new_coord + " to possibly become coordinator during concurrent startup. " + "My address is " + gms.local_addr); // GemStoneAddition - if there is concurrent startup, the other // client will be waiting the same amount of time, so increase the // join attempts in this VM to let the other client finish if (joinRetries < 2) { checkForTimeout(starttime); joinRetries++; } } } // joinRetries < maxRetries-1 else { if (trace) log.trace("I (" + myAddr + ") am not the coordinator and it is too" + " soon for an election"); } if (joinRetries > 0) { try { // GemStoneAddition //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "join sleep #2"); Util.sleep(gms.join_retry_timeout); //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "join sleep #2 done"); } catch (InterruptedException e) { Thread.currentThread().interrupt(); return false; // treat as failure } } continue; } // coord==null if (!coord.splitBrainEnabled() && this.gms.splitBrainDetectionEnabled) { throw gms.stack.gfBasicFunctions.getGemFireConfigException( "Group membership coordinator, " + coord + " does not have " + "network partition detection enabled, but this DistributedSystem has it enabled"); } boolean c6 = (((IpAddress)coord).getIpAddress() instanceof Inet6Address); boolean m6 = (((IpAddress)myAddr).getIpAddress() instanceof Inet6Address); if (c6 && !m6) { throw gms.stack.gfBasicFunctions.getGemFireConfigException( "Group membership coordinator, " + coord + ", is using IPv6 but this " + "process is using IPv4"); } if (m6 && !c6) { throw gms.stack.gfBasicFunctions.getGemFireConfigException( "Group membership coordinator, " + coord + ", is using IPv4 but this " + "process is using IPv6"); } } // !join_promise.hasResult() else { coord = coordSentJoin; } if (coord == null) { // GemStoneAddition // fix for NPE when a false join response has been received. This could // be from the retransmission of a response sent to a previous member // using the same address. In this case we haven't even gotten to // the point of sending a join request and the response should be ignored join_promise.reset(); continue; } try { if (coord.equals(gms.local_addr) && gms.local_addr.preferredForCoordinator()) { // GemStoneAddition - we can't usurp a group that was using a coordinator // that had the same address that this process is now using (bug #41772) if (((IpAddress)coord).getUniqueID() != ((IpAddress)gms.local_addr).getUniqueID()) { throw new ShunnedAddressException(); } // this member was elected by others as the coordinator if (becomeGroupCoordinator(gms.local_addr, null)) { return true; } else { coord = null; continue; // no need to sleep - there's another coordinator now } } // GemStoneAddition - check to see if a result came in while get_mbrs was being processed. // If there is one, just use it. if (!join_promise.hasResult()) { if(log.isDebugEnabled()) log.debug("sending join_req(" + myAddr + ") to " + coord); coordSentJoin = coord; sendJoinMessage(coord, myAddr); } if (log.isDebugEnabled()) { log.debug("Waiting for join response"); } // test hook for bug #49897 if (SLOW_JOIN) { synchronized(SLOW_JOIN_LOCK) { try { SLOW_JOIN_LOCK.wait(); } catch (InterruptedException e) { // the test will interrupt. Set the interrupt flag // so the Promise.getResult() call will run into it Thread.currentThread().interrupt(); } } } rsp=(JoinRsp)join_promise.getResult(gms.join_timeout); // bug #49897 - don't keep going if the thread's been interrupted if (Thread.currentThread().isInterrupted()) { throw gms.stack.gfBasicFunctions.getSystemConnectException(ExternalStrings.ClientGmsImpl_JOIN_INTERRUPTED.toLocalizedString()); } if(rsp == null) { if(warn && !leaving /* GemStoneAddition */) log.getLogWriter().warning(ExternalStrings.ClientGmsImpl_JOIN_0__SENT_TO__1__TIMED_OUT_RETRYING, new Object[] {myAddr, coord}); } else { if (log.isDebugEnabled()) { log.debug("Got join response: " + rsp); } // GemStoneAddition - birth view ID if (rsp.view != null && rsp.view.getVid() != null) { ((IpAddress)gms.local_addr).setBirthViewId(rsp.view.getVid().getId()); } if(rsp.getFailReason() != null){ if (rsp.getFailReason().equals(JoinRsp.SHUNNED_ADDRESS)) { throw new ShunnedAddressException(); } if (rsp.getFailReason().contains("Rejecting the attempt of a member using an older version") || rsp.getFailReason().contains("15806")) { throw gms.stack.gfBasicFunctions.getSystemConnectException(rsp.getFailReason()); } throw gms.stack.gfBasicFunctions.getAuthenticationFailedException(rsp.getFailReason()); } coord = rsp.getView().getCreator(); gms.notifyOfCoordinator(coord); // 1. Install digest tmp_digest=rsp.getDigest(); tmp_view=rsp.getView(); if(tmp_digest == null || tmp_view == null) { if(log.isErrorEnabled()) log.error(ExternalStrings.ClientGmsImpl_DIGEST_OR_VIEW_OF_JOIN_RESPONSE_IS_NULL); } else { // GemStoneAddition - commented out inc of highSeqno because this // does not work if the view is not multicast. In view of this there // must be a retransmission protocol. // tmp_digest.incrementHighSeqno(coord); // see DESIGN for an explanantion if(log.isDebugEnabled()) log.debug("digest is " + tmp_digest); gms.setDigest(tmp_digest); // 2. Install view if(log.isDebugEnabled()) log.debug("[" + gms.local_addr + "]: JoinRsp=" + rsp.getView() + " [size=" + rsp.getView().size() + "]\n\n"); if(!installView(tmp_view)) { if(log.isErrorEnabled()) log.error(ExternalStrings.ClientGmsImpl_VIEW_INSTALLATION_FAILED_RETRYING_TO_JOIN_GROUP); continue; } // send VIEW_ACK to sender of view Message view_ack=new Message(coord, null, null); GMS.GmsHeader tmphdr=new GMS.GmsHeader(GMS.GmsHeader.VIEW_ACK); view_ack.putHeader(GMS.name, tmphdr); // GemStoneAddition: bug #49261 - do not send the view // so that the ack-collector will accept this as an ack // for the view about to be cast by the coordinator view_ack.setObject(null); gms.passDown(new Event(Event.MSG, view_ack)); gms.passUp(new Event(Event.BECOME_SERVER)); gms.passDown(new Event(Event.BECOME_SERVER)); return true; } } } catch (ShunnedAddressException e) { System.setProperty("gemfire.jg-bind-port", "0"); // for testing throw e; } catch (RuntimeException e) { String name = e.getClass().getSimpleName(); if (name.equals("AuthenticationFailedException")) { if (log.isDebugEnabled()) { log.debug("AuthenticationFailedException=" + e.toString() ); } throw e; } else if (name.equals("SystemConnectException")) { throw e; } if (log.getLogWriter().infoEnabled()) { log.getLogWriter().info(ExternalStrings.UnexpectedException, e); } } catch (Exception e) { if (log.getLogWriter().infoEnabled()) { log.getLogWriter().info(ExternalStrings.UnexpectedException, e); } } if (joinRetries > 0) { try { // GemStoneAddition //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "join sleep #3"); Util.sleep(gms.join_retry_timeout); //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "join sleep #3 done"); } catch (InterruptedException e) { Thread.currentThread().interrupt(); return false; // treat as failure } } } if (missing_mbrs != null && missing_mbrs.size() > 0) { log.getLogWriter().info(ExternalStrings.DEBUG, "missing ping responses from " + missing_mbrs); return false; } return true; } // GemStoneAddition: check to see if join attempts have timed out private void checkForTimeout(long starttime) { if ((starttime + (2 * gms.join_timeout)) < System.currentTimeMillis()) { if (!gms.stack.getChannel().closing()) { log.getLogWriter().fine("GMS client is timing out and forcing an exit"); } throw gms.stack.gfBasicFunctions.getGemFireConfigException("Unable to contact a Locator service. " + "Operation either timed out, was stopped or Locator does not exist."); } } @Override // GemStoneAddition public void leave(Address mbr) { leaving=true; wrongMethod("leave"); } @Override // GemStoneAddition public void handleJoinResponse(JoinRsp join_rsp) { if (log.isDebugEnabled()) { log.getLogWriter().info(ExternalStrings.DEBUG, "Received join response " + join_rsp); } while (SLOW_JOIN) { // test hook log.getLogWriter().info(ExternalStrings.DEBUG, "delaying delivery of join response"); try { Thread.sleep(5000); } catch (InterruptedException e) { return; } } join_promise.setResult(join_rsp); // will wake up join() method //log.getLogWriterI18n().info(JGroupsStrings.DEBUG, "Set join response in promise"); } @Override // GemStoneAddition public void handleLeaveResponse(String reason) { // GemStoneAddition - added reason } // GemStoneAddition - optimized view casting @Override public void handleJoinsAndLeaves(List joins, List leaves, List suspects, List suspectReasons, boolean forceInclusion) {} // @Override // GemStoneAddition // public void suspect(Address mbr) { // } @Override // GemStoneAddition public void unsuspect(Address mbr) { } @Override // GemStoneAddition public void handleJoin(Address mbr) { } // @Override // GemStoneAddition // public void handleJoin(List mbrList) { // GemStoneAddition // } /** Returns false. Clients don't handle leave() requests */ public void handleLeave(Address mbr, boolean suspected) { } // GemStoneAddition @Override // GemStoneAddition public void handleLeave(List memberList, boolean suspected, List reasons, boolean forceInclusion) { } /** * GemStoneAddition - handle get_view_rsp when becoming * coordinator of existing group */ @Override // GemStoneAddition public synchronized void handleGetViewResponse(JoinRsp response) { synchronized (this.getViewLock) { if (this.getViewResponse != null) { if (this.getViewResponse.getView().getCreator().equals(response.getView().getCreator()) && this.getViewResponse.getView().getVid().compareTo(response.getView().getVid()) < 0) { // newer view - use it this.getViewResponses++; this.getViewResponse = response; } } else { this.getViewResponse = response; this.getViewResponses++; } this.getViewLock.notify(); } } @Override // GemStoneAddition public void handleViewChange(View new_view, Digest digest) { } /** * Called by join(). Installs the view returned by calling Coord.handleJoin() and * becomes coordinator. */ private boolean installView(View new_view) { Vector mems=new_view.getMembers(); if(log.isDebugEnabled()) log.debug("new_view=" + new_view); if(gms.local_addr == null || mems == null || !mems.contains(gms.local_addr)) { if(log.isErrorEnabled()) log.error("I (" + gms.local_addr + ") am not member of " + mems + ", will not install view"); return false; } gms.installView(new_view); gms.becomeParticipant(); gms.passUp(new Event(Event.BECOME_SERVER)); gms.passDown(new Event(Event.BECOME_SERVER)); return true; } /** Returns immediately. Clients don't handle suspect() requests */ // @Override // GemStoneAddition // public void handleSuspect(Address mbr) { // } @Override // GemStoneAddition public boolean handleUpEvent(Event evt) { Vector tmp; switch(evt.getType()) { case Event.FIND_INITIAL_MBRS_OK: tmp=(Vector)evt.getArg(); synchronized(initial_mbrs) { if (!initial_mbrs_received) { // GemStoneAddition - don't update if thread was interrupted if(tmp != null && tmp.size() > 0) { initial_mbrs.addAll(tmp); } initial_mbrs_received=true; //if (initial_mbrs.size() == 0) { // log.getLogWriter().warning("received FIND_INITIAL_MBRS_OK event with no members", new Exception("Stack trace")); //} initial_mbrs.notifyAll(); } } return false; // don't pass up the stack case Event.FIND_INITIAL_MBRS_FAILED: // GemStoneAddition - requiredMembers. See bug #30341 if (log.getLogWriter().fineEnabled()) { log.getLogWriter().fine("received FIND_INITIAL_MBRS_FAILED event in ClientGmsImpl with " + evt.getArg()); } Set missing = (Set)evt.getArg(); synchronized(initial_mbrs) { if (!initial_mbrs_received) { initial_mbrs_received = true; missing_mbrs = missing; initial_mbrs.notifyAll(); } } return false; case Event.EXIT: // GemStoneAddition - stop looking if we exit synchronized(initial_mbrs) { initial_mbrs_received=true; initial_mbrs.notifyAll(); } stop(); break; } return true; } /* --------------------------- Private Methods ------------------------------------ */ // GemStoneAddition - lastAttempt is used to prevent sending join to the // same recipient multiple times. The UNICAST protocol handles retransmission Address lastAttempt; void sendJoinMessage(Address coord, Address mbr) { Message msg; GMS.GmsHeader hdr; // GemStoneAddition: // if reconnecting we will make multiple attempts with the same coordinator // because it might be spinning up at the same time. Otherwise, if not reconnecting, // we don't want to keep trying with the same coordinator because if it's not responding // it's probably not there if (lastAttempt == null || (this.gms.stack.gfPeerFunctions.isReconnectingDS() || !coord.equals(lastAttempt))) { Address me = mbr; if (gms.stack.gfPeerFunctions.isReconnectingDS()) { // if reconnecting blow out the processID so the address won't equal() // our old address when it reaches the coordinator. This avoids problems // in UNICAST and other places where the address is used as a key and our // old address might still be lingering in the system me = (Address)(((IpAddress)mbr).clone()); ((IpAddress)me).setProcessId(0); } log.getLogWriter().info(ExternalStrings. ClientGmsImpl_ATTEMPTING_TO_JOIN_DS_WHOSE_MEMBERSHIP_COORDINATOR_IS_0_USING_ID_1, new Object[]{coord, me}); msg=new Message(coord, null, null); hdr=new GMS.GmsHeader(GMS.GmsHeader.JOIN_REQ, me); msg.putHeader(gms.getName(), hdr); lastAttempt = null; // set to null in case there is an exception in passDown() gms.passDown(new Event(Event.MSG, msg)); lastAttempt = coord; } } /** * Pings initial members. Removes self before returning vector of initial members. * Uses IP multicast or gossiping, depending on parameters. */ void findInitialMembers() { PingRsp ping_rsp; synchronized(initial_mbrs) { findInitialMbrsAttempts++; // GemStoneAddition initial_mbrs.removeAllElements(); initial_mbrs_received=false; gms.passDown(new Event(Event.FIND_INITIAL_MBRS)); // the initial_mbrs_received flag is needed when passDown() is executed on the same thread, so when // it returns, a response might actually have been received (even though the initial_mbrs might still be empty) while/*GemStoneAddition*/ (initial_mbrs_received == false) { try { initial_mbrs.wait(); //gms.join_timeout+1000); // GemStoneAddition bug #34274 - don't wait forever } catch(InterruptedException e) { // GemStoneAddition Thread.currentThread().interrupt(); initial_mbrs_received = true; // suppress any late updates // process whatever he have now. Note that since we are // stilled synchronized on initial_mbrs, asynchronous updates // won't come in before we return a result. } } for(int i=0; i < initial_mbrs.size(); i++) { ping_rsp=(PingRsp)initial_mbrs.elementAt(i); if(ping_rsp.own_addr != null && gms.local_addr != null && ping_rsp.own_addr.equals(gms.local_addr)) { initial_mbrs.removeElementAt(i); break; } } if (findInitialMbrsAttempts > 2) { // GemStoneAddition: bug #50785 - if we have made some rounds using // best-guess coordinator candidates from other processes that have // yet to join the group then we stop trusting this gossip // because it can just ping-pong around between members that are // still trying to join. See PingWaiter.getPossibleCoordinator(). List removals = new ArrayList(initial_mbrs.size()); for(int i=0; i < initial_mbrs.size(); i++) { ping_rsp=(PingRsp)initial_mbrs.elementAt(i); if(ping_rsp.own_addr != null && !ping_rsp.isServer() && !ping_rsp.getCoordAddress().equals(ping_rsp.own_addr)) { removals.add(ping_rsp); } } initial_mbrs.removeAll(removals); } } } /** The coordinator is determined by a majority vote. If there are an equal number of votes for more than 1 candidate, we determine the winner randomly. */ private Address determineCoord(Vector mbrs) { PingRsp mbr; Hashtable votes; int count, most_votes; Address winner=null, tmp; if(mbrs == null || mbrs.size() < 1) return null; votes=new Hashtable(5); // count *all* the votes (unlike the 2000 election) for(int i=0; i < mbrs.size(); i++) { mbr=(PingRsp)mbrs.elementAt(i); if(mbr.is_server && mbr.coord_addr != null) { if(!votes.containsKey(mbr.coord_addr)) votes.put(mbr.coord_addr, Integer.valueOf(1)); else { count=((Integer)votes.get(mbr.coord_addr)).intValue(); votes.put(mbr.coord_addr, Integer.valueOf(count + 1)); } } } if(votes.size() > 1) { /*if(warn)*/ log.getLogWriter().warning(ExternalStrings.ClientGmsImpl_THERE_WAS_MORE_THAN_1_CANDIDATE_FOR_COORDINATOR__0, votes); } else { if(log.isDebugEnabled()) log.debug("election results: " + votes); } // determine who got the most votes most_votes=0; for(Enumeration e=votes.keys(); e.hasMoreElements();) { tmp=(Address)e.nextElement(); count=((Integer)votes.get(tmp)).intValue(); if(count > most_votes) { winner=tmp; // fixed July 15 2003 (patch submitted by Darren Hobbs, patch-id=771418) most_votes=count; } } votes.clear(); return winner; } void becomeSingletonMember(Address mbr) { Digest initial_digest; ViewId view_id; Vector mbrs=new Vector(1); // set the initial digest (since I'm the first member) initial_digest=new Digest(1); // 1 member (it's only me) initial_digest.add(gms.local_addr, 0, 0); // initial seqno mcast by me will be 1 (highest seen +1) gms.setDigest(initial_digest); view_id=new ViewId(mbr); // create singleton view with mbr as only member mbrs.addElement(mbr); gms.installView(new View(view_id, mbrs)); gms.becomeCoordinator(null); // not really necessary - installView() should do it gms.passUp(new Event(Event.BECOME_SERVER)); gms.passDown(new Event(Event.BECOME_SERVER)); gms.notifyOfCoordinator(gms.local_addr); //log.getLogWriter().warning("Created new group with view " + gms.view_id); if(log.isDebugEnabled()) log.debug("created group (first member). My view is " + gms.view_id + ", impl is " + gms.getImpl().getClass().getName()); } /** * GemStoneAddition - new protocol to allow a member to assume the role * of coordinator in a system that has lost all eligible coordinators * @param mbr the address of this stack * @param failedCoordinator (optional) the address of the coordinator that held the view * @return true if able to become coordinator, false if not */ boolean becomeGroupCoordinator(Address mbr, Address failedCoordinator) { int sentRequests = 0; Digest initial_digest; ViewId view_id; Vector mbrs; Vector imbrs; synchronized(initial_mbrs) { imbrs = (Vector)initial_mbrs.clone(); } // get the current view from one of the members and then // form a new group GMS.GmsHeader hdr = new GMS.GmsHeader(GMS.GmsHeader.GET_VIEW); for (int i=0; i= sentRequests || timeLeft <= 0) { break; } try { this.getViewLock.wait(timeLeft); } catch (InterruptedException ie) { Thread.currentThread().interrupt(); throw gms.stack.gfBasicFunctions.getSystemConnectException(ExternalStrings.ClientGmsImpl_INTERRUPTED_WHILE_BECOMING_COORDINATOR_OF_EXISTING_GROUP.toLocalizedString()); } } } if (this.getViewResponse == null) { throw gms.stack.gfBasicFunctions.getSystemConnectException(ExternalStrings.ClientGmsImpl_UNABLE_TO_BECOME_COORDINATOR_OF_EXISTING_GROUP_BECAUSE_NO_VIEW_RESPONSES_WERE_RECEIVED.toLocalizedString()); } View theView = this.getViewResponse.getView(); Address theCreator = theView.getCreator(); if (theCreator != null && theCreator.preferredForCoordinator()) { if (failedCoordinator == null && theView.containsMember(theCreator)) { // locator was shut down and restarted. Other members reported no coordinator // but now there is one, so two eligible coordinators are being started // simultaneously. Return false to allow the other one to win // log.getLogWriterI18n().info(JGroupsStrings.ONE_ARG, "DEBUG: failedCoordinator is null and view creator is " // + theCreator); return false; } if (failedCoordinator != null && !theCreator.equals(failedCoordinator)) { // the locator or its machine failed and this is a new locator starting // up. Another locator has already installed itself as the coordinator, // so return false to let it win // log.getLogWriterI18n().info(JGroupsStrings.ONE_ARG, "DEBUG: failedCoordinator is " + failedCoordinator + " and view creator is " // + theCreator); return false; } } mbrs = theView.getMembers(); mbrs.add(mbr); // add myself in (was .add(0, mbr) prior to 2013 cedar release but this caused elder init problems with colocated secure locators) // create the initial digest. it will be filled in with gossip soon enough initial_digest=this.getViewResponse.getDigest(); initial_digest.add(gms.local_addr, 0, 0); // initial seqno mcast by me will be 1 (highest seen +1) gms.setDigest(initial_digest); view_id=new ViewId(mbr, theView.getVid().getId()+1); // create singleton view with mbr as only member View new_view = new View(view_id, mbrs); gms.installView(new_view); gms.becomeCoordinator(null); // not really necessary - installView() should do it gms.ucastViewChange(new_view); // tell the world gms.passUp(new Event(Event.BECOME_SERVER)); gms.passDown(new Event(Event.BECOME_SERVER)); gms.notifyOfCoordinator(gms.local_addr); log.getLogWriter().info( ExternalStrings. ClientGmsImpl_RECREATED_DISTRIBUTED_SYSTEM_GROUP_0, gms.view); return true; } // @Override // GemStoneAddition // public void suspect(Address mbr, String reason) { // suspect(mbr); // } /* (non-Javadoc) GemStoneAddition * @see com.gemstone.org.jgroups.protocols.pbcast.GmsImpl#handleAlreadyJoined(com.gemstone.org.jgroups.Address) */ @Override // GemStoneAddition public void handleAlreadyJoined(Address mbr) { } }





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