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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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package org.jgroups.protocols.pbcast;

import org.jgroups.*;
import org.jgroups.util.Digest;
import org.jgroups.util.Promise;

import java.util.ArrayList;
import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.List;


/**
 * @author Bela Ban
 */
public class ParticipantGmsImpl extends ServerGmsImpl {
    private final List     suspected_mbrs=new ArrayList<>(11);
    private final Promise  leave_promise=new Promise<>();


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


    public void init() throws Exception {
        super.init();
        suspected_mbrs.clear();
        leave_promise.reset();
    }

    public void join(Address mbr, boolean useFlushIfPresent) {
        wrongMethod("join");
    }

    public void joinWithStateTransfer(Address mbr,boolean useFlushIfPresent) {
        wrongMethod("join");
    }


    /**
     * Loop: determine coord. If coord is me --> handleLeave().
     * Else send handleLeave() to coord until success
     */
    public void leave(Address mbr) {
        Address coord;
        int max_tries=3;

        leave_promise.reset();

        if(mbr.equals(gms.local_addr))
            leaving=true;

        while((coord=gms.determineCoordinator()) != null && max_tries-- > 0) {
            if(gms.local_addr.equals(coord)) {            // I'm the coordinator
                gms.becomeCoordinator();
                // gms.getImpl().handleLeave(mbr, false);    // regular leave
                gms.getImpl().leave(mbr);    // regular leave
                return;
            }

            log.trace("%s: sending LEAVE request to %s", gms.local_addr, coord);
            sendLeaveMessage(coord, mbr);
            Boolean result=leave_promise.getResult(gms.leave_timeout);
            if(result != null) {
                log.trace("%s: got LEAVE response from %s", gms.local_addr, coord);
                break;
            }
        }
        gms.becomeClient();
    }


    /** In case we get a different JOIN_RSP from a previous JOIN_REQ sent by us (as a client), we simply apply the
     * new view if it is greater than ours
     *
     * @param join_rsp
     */
    public void handleJoinResponse(JoinRsp join_rsp) {
        View v=join_rsp.getView();
        ViewId tmp_vid=v != null? v.getViewId() : null;
        ViewId my_view=gms.getViewId();
        if(tmp_vid != null && my_view != null && tmp_vid.compareToIDs(my_view) > 0) {
            Digest d=join_rsp.getDigest();
            gms.installView(v, d);
        }
    }

    public void handleLeaveResponse() {
        leave_promise.setResult(true);  // unblocks thread waiting in leave()
    }


    public void suspect(Address mbr) {
        Collection suspected=new LinkedHashSet<>(1);
        suspected.add(new Request(Request.SUSPECT,mbr,true));
        handleMembershipChange(suspected);
    }


    /** Removes previously suspected member from list of currently suspected members */
    public void unsuspect(Address mbr) {
        if(mbr != null)
            suspected_mbrs.remove(mbr);
    }


    public void handleMembershipChange(Collection requests) {
        Collection suspectedMembers=new LinkedHashSet<>(requests.size());
        for(Request req: requests)
            if(req.type == Request.SUSPECT)
                suspectedMembers.add(req.mbr);

        if(suspectedMembers.isEmpty())
            return;

        for(Address mbr: suspectedMembers)
            if(!suspected_mbrs.contains(mbr))
                suspected_mbrs.add(mbr);

        if(wouldIBeCoordinator()) {
            log.debug("%s: members are %s, coord=%s: I'm the new coord !", gms.local_addr, gms.members, gms.local_addr);

            gms.becomeCoordinator();
            for(Address mbr: suspected_mbrs) {
                gms.getViewHandler().add(new Request(Request.SUSPECT, mbr, true));
                gms.ack_collector.suspect(mbr);
            }
            suspected_mbrs.clear();
        }
    }


    /**
     * If we are leaving, we have to wait for the view change (last msg in the current view) that
     * excludes us before we can leave.
     * @param new_view The view to be installed
     * @param digest   If view is a MergeView, digest contains the seqno digest of all members and has to
     *                 be set by GMS
     */
    public void handleViewChange(View new_view, Digest digest) {
        suspected_mbrs.clear();
        if(leaving && !new_view.containsMember(gms.local_addr)) // received a view in which I'm not member: ignore
            return;
        gms.installView(new_view, digest);
    }



    /* ---------------------------------- Private Methods --------------------------------------- */

    /**
     * Determines whether this member is the new coordinator given a list of suspected members.  This is
     * computed as follows: the list of currently suspected members (suspected_mbrs) is removed from the current
     * membership. If the first member of the resulting list is equals to the local_addr, then it is true,
     * otherwise false. Example: own address is B, current membership is {A, B, C, D}, suspected members are {A,
     * D}. The resulting list is {B, C}. The first member of {B, C} is B, which is equal to the
     * local_addr. Therefore, true is returned.
     */
    boolean wouldIBeCoordinator() {
        List mbrs=gms.computeNewMembership(gms.members.getMembers(), null, null, suspected_mbrs);
        if(mbrs.size() < 1) return false;
        Address new_coord=mbrs.get(0);
        return gms.local_addr.equals(new_coord);
    }


    void sendLeaveMessage(Address coord, Address mbr) {
        Message msg=new Message(coord).setFlag(Message.Flag.OOB)
          .putHeader(gms.getId(), new GMS.GmsHeader(GMS.GmsHeader.LEAVE_REQ, mbr));
        gms.getDownProtocol().down(new Event(Event.MSG, msg));
    }


    /* ------------------------------ End of Private Methods ------------------------------------ */

}