Package org.jgroups.protocols.pbcast

Class Merger

java.lang.Object
org.jgroups.protocols.pbcast.Merger
public class Merger extends Object
Handles merging. Called by CoordGmsImpl and ParticipantGmsImpl

  • Field Details

    • gms

      protected final GMS gms

    • log

      protected final Log log

    • merge_task

      protected final Merger.MergeTask merge_task

    • merge_rsps

      protected final ResponseCollector<MergeData> merge_rsps
      For MERGE_REQ/MERGE_RSP correlation, contains MergeData elements

    • digest_collector

      protected final ResponseCollector<Digest> digest_collector
      For GET_DIGEST / DIGEST_RSP correlation

    • merge_id

      protected MergeId merge_id

    • merge_id_history

      protected final BoundedList<MergeId> merge_id_history

    • merge_killer

      protected Future<?> merge_killer

  • Constructor Details

    • Merger

      public Merger(GMS gms)

  • Method Details

    • getMergeIdAsString

      public String getMergeIdAsString()

    • getMergeIdHistory

      public String getMergeIdHistory()

    • isMergeTaskRunning

      public boolean isMergeTaskRunning()

    • isMergeKillerTaskRunning

      public boolean isMergeKillerTaskRunning()

    • getMergeId

      public MergeId getMergeId()

    • isMergeInProgress

      public boolean isMergeInProgress()

    • matchMergeId

      public boolean matchMergeId(MergeId id)

    • setMergeId

      public boolean setMergeId(MergeId expected, MergeId new_value)

    • merge

      public void merge(Map<Address,View> views)
      Invoked upon receiving a MERGE event from the MERGE layer. Starts the merge protocol. See description of protocol in DESIGN.
      Parameters:
      views - A List of different views detected by the merge protocol, keyed by sender

    • handleMergeRequest

      public void handleMergeRequest(Address sender, MergeId merge_id, Collection<? extends Address> mbrs)
      Get the view and digest and send back both (MergeData) in the form of a MERGE_RSP to the sender. If a merge is already in progress, send back a MergeData with the merge_rejected field set to true.
      Parameters:
      sender - The address of the merge leader
      merge_id - The merge ID
      mbrs - The set of members from which we expect responses. Guaranteed to be non-null

    • handleMergeResponse

      public void handleMergeResponse(MergeData data, MergeId merge_id)

    • handleMergeView

      public void handleMergeView(MergeData data, MergeId merge_id)
      If merge_id is not equal to this.merge_id then discard. Else cast the view/digest to all members of this group.

    • handleMergeCancelled

      public void handleMergeCancelled(MergeId merge_id)

    • handleDigestResponse

      public void handleDigestResponse(Address sender, Digest digest)

    • sanitizeViews

      public static void sanitizeViews(Map<Address,View> map)
      Removes all members from a given view which don't have us in their view (https://issues.redhat.com/browse/JGRP-1061). Example: 
       A: AB
 B: AB
 C: ABC
      becomes 
       A: AB
 B: AB
 C: C // A and B don't have C in their views
      Parameters:
      map - A map of members and their associated views

    • determineMergeLeader

      protected Address determineMergeLeader(Map<Address,View> views)
      Returns the address of the merge leader

    • determineMergeCoords

      protected static Map<Address,Collection<Address>> determineMergeCoords(Map<Address,View> views)
      Needs to return a map of all subview coordinators and their views (as a collection of members). The merge policy is defined in https://issues.redhat.com/browse/JGRP-1910

    • _handleMergeRequest

      protected void _handleMergeRequest(Address sender, MergeId merge_id, Collection<? extends Address> mbrs) throws Exception
      Throws:
      Exception

    • sendMergeResponse

      protected void sendMergeResponse(Address sender, View view, Digest digest, MergeId merge_id)
      Send back a response containing view and digest to sender

    • sendMergeView

      protected void sendMergeView(Collection<Address> coords, MergeData combined_merge_data, MergeId merge_id)
      Sends the new view and digest to all subgroup coordinators. Each coord will in turn broadcast the new view and digest to all the members of its subgroup

    • sendMergeRejectedResponse

      protected void sendMergeRejectedResponse(Address sender, MergeId merge_id)

    • sendMergeCancelledMessage

      protected void sendMergeCancelledMessage(Collection<Address> coords, MergeId merge_id)

    • fetchDigestsFromAllMembersInSubPartition

      protected Digest fetchDigestsFromAllMembersInSubPartition(View view, MergeId merge_id)
      Multicasts a GET_DIGEST_REQ to all members of this sub partition and waits for all responses (GET_DIGEST_RSP) or N ms.

    • fixDigests

      protected void fixDigests()
      Fetches the digests from all members and installs them again. Used only for diagnosis and support; don't use this otherwise !

    • stop

      protected void stop()

    • cancelMerge

      protected void cancelMerge(MergeId id)

    • forceCancelMerge

      protected void forceCancelMerge()

    • startMergeKiller

      protected void startMergeKiller()

    • stopMergeKiller

      protected void stopMergeKiller()