/**
* Sets the new view and sends a VIEW_CHANGE event up and down the stack. If the view is a
* MergeView (subclass of View), then digest will be non-null and has to be set before installing
* the view.
*/
public void installView(View new_view, Digest digest) {
ViewId vid = new_view.getVid();
List<Address> mbrs = new_view.getMembers();
ltime =
Math.max(
vid.getId(),
ltime); // compute the logical time, regardless of whether the view is accepted
// Discards view with id lower than or equal to our own. Will be installed without check if it
// is the first view
if (view != null) {
ViewId view_id = view.getViewId();
int rc = vid.compareToIDs(view_id);
if (rc <= 0) {
if (log.isWarnEnabled()
&& rc < 0
&& log_view_warnings) { // only scream if view is smaller, silently discard same views
log.warn(
local_addr
+ ": received view < current view;"
+ " discarding it (current vid: "
+ view_id
+ ", new vid: "
+ vid
+ ')');
}
return;
}
}
/* Check for self-inclusion: if I'm not part of the new membership, I just discard it.
This ensures that messages sent in view V1 are only received by members of V1 */
if (!mbrs.contains(local_addr)) {
if (log.isWarnEnabled() && log_view_warnings)
log.warn(local_addr + ": not member of view " + new_view.getViewId() + "; discarding it");
return;
}
if (digest != null) {
if (new_view instanceof MergeView) mergeDigest(digest);
else setDigest(digest);
}
if (log.isDebugEnabled()) log.debug(local_addr + ": installing view " + new_view);
Event view_event;
synchronized (members) {
view = new View(new_view.getVid(), new_view.getMembers());
view_event = new Event(Event.VIEW_CHANGE, new_view);
// Set the membership. Take into account joining members
if (!mbrs.isEmpty()) {
members.set(mbrs);
tmp_members.set(members);
joining.removeAll(mbrs); // remove all members in mbrs from joining
// remove all elements from 'leaving' that are not in 'mbrs'
leaving.retainAll(mbrs);
tmp_members.add(joining); // add members that haven't yet shown up in the membership
tmp_members.remove(
leaving); // remove members that haven't yet been removed from the membership
// add to prev_members
for (Address addr : mbrs) {
if (!prev_members.contains(addr)) prev_members.add(addr);
}
}
Address coord = determineCoordinator();
if (coord != null && coord.equals(local_addr) && !haveCoordinatorRole()) {
becomeCoordinator();
} else {
if (haveCoordinatorRole() && !local_addr.equals(coord)) {
becomeParticipant();
merge_ack_collector.reset(null); // we don't need this one anymore
}
}
}
// - Changed order of passing view up and down (http://jira.jboss.com/jira/browse/JGRP-347)
// - Changed it back (bela Sept 4 2007): http://jira.jboss.com/jira/browse/JGRP-564
// - Moved sending up view_event out of the synchronized block (bela Nov 2011)
down_prot.down(view_event); // needed e.g. by failure detector or UDP
up_prot.up(view_event);
List<Address> tmp_mbrs = new_view.getMembers();
ack_collector.retainAll(tmp_mbrs);
merge_ack_collector.retainAll(tmp_mbrs);
if (new_view instanceof MergeView) merger.forceCancelMerge();
if (stats) {
num_views++;
prev_views.add(new Tuple<View, Long>(new_view, System.currentTimeMillis()));
}
}
@SuppressWarnings("unchecked")
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG:
Message msg = (Message) evt.getArg();
GmsHeader hdr = (GmsHeader) msg.getHeader(this.id);
if (hdr == null) break;
switch (hdr.type) {
case GmsHeader.JOIN_REQ:
view_handler.add(
new Request(Request.JOIN, hdr.mbr, false, null, hdr.useFlushIfPresent));
break;
case GmsHeader.JOIN_REQ_WITH_STATE_TRANSFER:
view_handler.add(
new Request(
Request.JOIN_WITH_STATE_TRANSFER, hdr.mbr, false, null, hdr.useFlushIfPresent));
break;
case GmsHeader.JOIN_RSP:
impl.handleJoinResponse(hdr.join_rsp);
break;
case GmsHeader.LEAVE_REQ:
if (hdr.mbr == null) return null;
view_handler.add(new Request(Request.LEAVE, hdr.mbr, false));
break;
case GmsHeader.LEAVE_RSP:
impl.handleLeaveResponse();
break;
case GmsHeader.VIEW:
View new_view = hdr.view;
if (new_view == null) return null;
Address coord = msg.getSrc();
if (!new_view.containsMember(coord)) {
sendViewAck(
coord); // we need to send the ack first, otherwise the connection is removed
impl.handleViewChange(new_view, hdr.my_digest);
} else {
impl.handleViewChange(new_view, hdr.my_digest);
sendViewAck(coord); // send VIEW_ACK to sender of view
}
break;
case GmsHeader.VIEW_ACK:
Address sender = msg.getSrc();
ack_collector.ack(sender);
return null; // don't pass further up
case GmsHeader.MERGE_REQ:
impl.handleMergeRequest(msg.getSrc(), hdr.merge_id, hdr.mbrs);
break;
case GmsHeader.MERGE_RSP:
MergeData merge_data =
new MergeData(msg.getSrc(), hdr.view, hdr.my_digest, hdr.merge_rejected);
if (log.isTraceEnabled()) {
log.trace(
local_addr
+ ": got merge response from "
+ msg.getSrc()
+ ", merge_id="
+ hdr.merge_id
+ ", merge data is "
+ merge_data);
}
impl.handleMergeResponse(merge_data, hdr.merge_id);
break;
case GmsHeader.INSTALL_MERGE_VIEW:
impl.handleMergeView(
new MergeData(msg.getSrc(), hdr.view, hdr.my_digest), hdr.merge_id);
break;
case GmsHeader.INSTALL_DIGEST:
Digest tmp = hdr.my_digest;
down_prot.down(new Event(Event.MERGE_DIGEST, tmp));
break;
case GmsHeader.INSTALL_MERGE_VIEW_OK:
// [JGRP-700] - FLUSH: flushing should span merge
merge_ack_collector.ack(msg.getSrc());
break;
case GmsHeader.CANCEL_MERGE:
// [JGRP-524] - FLUSH and merge: flush doesn't wrap entire merge process
impl.handleMergeCancelled(hdr.merge_id);
break;
case GmsHeader.GET_DIGEST_REQ:
// only handle this request if it was sent by the coordinator (or at least a member) of
// the current cluster
synchronized (members) {
if (!members.contains(msg.getSrc())) break;
}
// discard my own request:
if (msg.getSrc().equals(local_addr)) return null;
if (hdr.merge_id != null
&& !(merger.matchMergeId(hdr.merge_id) || merger.setMergeId(null, hdr.merge_id)))
return null;
// fetch only my own digest
Digest digest = (Digest) down_prot.down(new Event(Event.GET_DIGEST, local_addr));
if (digest != null) {
GmsHeader rsp_hdr = new GmsHeader(GmsHeader.GET_DIGEST_RSP);
rsp_hdr.my_digest = digest;
Message get_digest_rsp = new Message(msg.getSrc(), null, null);
get_digest_rsp.setFlag(Message.OOB);
get_digest_rsp.putHeader(this.id, rsp_hdr);
down_prot.down(new Event(Event.MSG, get_digest_rsp));
}
break;
case GmsHeader.GET_DIGEST_RSP:
Digest digest_rsp = hdr.my_digest;
impl.handleDigestResponse(msg.getSrc(), digest_rsp);
break;
default:
if (log.isErrorEnabled()) log.error("GmsHeader with type=" + hdr.type + " not known");
}
return null; // don't pass up
case Event.SUSPECT:
Object retval = up_prot.up(evt);
Address suspected = (Address) evt.getArg();
view_handler.add(new Request(Request.SUSPECT, suspected, true));
ack_collector.suspect(suspected);
merge_ack_collector.suspect(suspected);
return retval;
case Event.UNSUSPECT:
impl.unsuspect((Address) evt.getArg());
return null; // discard
case Event.MERGE:
view_handler.add(
new Request(Request.MERGE, null, false, (Map<Address, View>) evt.getArg()));
return null; // don't pass up
case Event.IS_MERGE_IN_PROGRESS:
return merger.isMergeInProgress();
}
return up_prot.up(evt);
}
/**
* Broadcasts the new view and digest, and waits for acks from all members in the list given as
* argument. If the list is null, we take the members who are part of new_view
*/
public void castViewChange(
View new_view, Digest digest, JoinRsp jr, Collection<Address> newMembers) {
if (log.isTraceEnabled())
log.trace(local_addr + ": mcasting view " + new_view + " (" + new_view.size() + " mbrs)\n");
// Send down a local TMP_VIEW event. This is needed by certain layers (e.g. NAKACK) to compute
// correct digest
// in case client's next request (e.g. getState()) reaches us *before* our own view change
// multicast.
// Check NAKACK's TMP_VIEW handling for details
down_prot.up(new Event(Event.TMP_VIEW, new_view));
down_prot.down(new Event(Event.TMP_VIEW, new_view));
List<Address> ackMembers = new ArrayList<Address>(new_view.getMembers());
if (newMembers != null && !newMembers.isEmpty()) ackMembers.removeAll(newMembers);
Message view_change_msg = new Message(); // bcast to all members
GmsHeader hdr = new GmsHeader(GmsHeader.VIEW, new_view);
hdr.my_digest = digest;
view_change_msg.putHeader(this.id, hdr);
// If we're the only member the VIEW is broadcast to, let's simply install the view directly,
// without
// sending the VIEW multicast ! Or else N-1 members drop the multicast anyway...
if (local_addr != null && ackMembers.size() == 1 && ackMembers.get(0).equals(local_addr)) {
// we need to add the message to the retransmit window (e.g. in NAKACK), so (1) it can be
// retransmitted and
// (2) we increment the seqno (otherwise, we'd return an incorrect digest)
down_prot.down(new Event(Event.ADD_TO_XMIT_TABLE, view_change_msg));
impl.handleViewChange(new_view, digest);
} else {
if (!ackMembers.isEmpty()) ack_collector.reset(ackMembers);
down_prot.down(new Event(Event.MSG, view_change_msg));
try {
if (!ackMembers.isEmpty()) {
ack_collector.waitForAllAcks(view_ack_collection_timeout);
if (log.isTraceEnabled())
log.trace(
local_addr
+ ": received all "
+ ack_collector.expectedAcks()
+ " ACKs from members for view "
+ new_view.getVid());
}
} catch (TimeoutException e) {
if (log_collect_msgs && log.isWarnEnabled()) {
log.warn(
local_addr
+ ": failed to collect all ACKs (expected="
+ ack_collector.expectedAcks()
+ ") for view "
+ new_view.getViewId()
+ " after "
+ view_ack_collection_timeout
+ "ms, missing ACKs from "
+ ack_collector.printMissing());
}
}
}
if (jr != null && (newMembers != null && !newMembers.isEmpty())) {
ack_collector.reset(new ArrayList<Address>(newMembers));
for (Address joiner : newMembers) {
sendJoinResponse(jr, joiner);
}
try {
ack_collector.waitForAllAcks(view_ack_collection_timeout);
if (log.isTraceEnabled())
log.trace(
local_addr
+ ": received all ACKs ("
+ ack_collector.expectedAcks()
+ ") from joiners for view "
+ new_view.getVid());
} catch (TimeoutException e) {
if (log_collect_msgs && log.isWarnEnabled()) {
log.warn(
local_addr
+ ": failed to collect all ACKs (expected="
+ ack_collector.expectedAcks()
+ ") for unicast view "
+ new_view
+ " after "
+ view_ack_collection_timeout
+ "ms, missing ACKs from "
+ ack_collector.printMissing());
}
}
}
}