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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and JMS 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;

import org.jgroups.Address;
import org.jgroups.annotations.ManagedOperation;
import org.jgroups.util.Util;

import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.concurrent.atomic.AtomicBoolean;

/**
 * Failure detection based on simple heartbeat protocol. Every member periodically (interval ms) multicasts a heartbeat.
 * Every member also maintains a table of all members (minus itself). When data or a heartbeat from P is received,
 * we set the flag associated with P to true. Periodically, we check for expired members, and suspect those whose flag
 * is false (no heartbeat or message received within timeout ms).
 *
 * @author  Bela Ban
 * @version 3.5
 */
public class FD_ALL2 extends FailureDetection {

    // Map of addresses and timestamps of last updates
    protected final Map timestamps=Util.createConcurrentMap();

    protected Map getTimestamps()                {return timestamps;}
    protected long           getTimeoutCheckInterval()      {return timeout;}

    @ManagedOperation(description="Prints timestamps")
    public String printTimestamps() {
        return _printTimestamps();
    }

    @Override protected void update(Address sender, boolean log_msg, boolean skip_if_exists) {
        if(sender != null && !sender.equals(local_addr)) {
            AtomicBoolean heartbeat_received=timestamps.get(sender);
            if(heartbeat_received != null) {
                if(!skip_if_exists)
                    heartbeat_received.compareAndSet(false, true);
            }
            else
                timestamps.putIfAbsent(sender, new AtomicBoolean(true));
        }
        if(log_msg && log.isTraceEnabled())
            log.trace("%s: received heartbeat from %s", local_addr, sender);
    }



    protected  boolean needsToBeSuspected(Address mbr, T value) {
        AtomicBoolean val=(AtomicBoolean)value;
        if(!val.compareAndSet(true, false)) {
            log.debug("%s: haven't received a heartbeat from %s in timeout period (%d ms), adding it to suspect list",
                      local_addr, mbr, timeout);
            return true;
        }
        return false;
    }

    protected String getTimeoutCheckerInfo() {
        return FD_ALL2.class.getSimpleName() + ": " + getClass().getSimpleName() + " (timeout=" + timeout + " ms)";
    }

    protected String _printTimestamps() {
        StringBuilder sb=new StringBuilder();
        for(Iterator> it=timestamps.entrySet().iterator(); it.hasNext();) {
            Entry entry=it.next();
            sb.append(entry.getKey()).append(": received=").append(entry.getValue()).append("\n");
        }
        return sb.toString();
    }
}