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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;

import org.jgroups.Message;
import org.jgroups.annotations.MBean;
import org.jgroups.annotations.ManagedAttribute;
import org.jgroups.stack.Protocol;
import org.jgroups.util.AverageMinMax;
import org.jgroups.util.MessageBatch;
import org.jgroups.util.Util;

/**
 * Protocol measuring delivery times. Should be placed towards the top of the stack.
 * JIRA: https://issues.jboss.org/browse/JGRP-2101
 * @author Bela Ban
 * @since  4.0
 */
@MBean(description="Measures message delivery times")
public class DELIVERY_TIME extends Protocol {
    protected AverageMinMax delivery_times=new AverageMinMax();

    @ManagedAttribute(description="Average delivery time (in microseconds). This is computed as the average " +
      "delivery time for single messages, plus the delivery time for batches")
    public double getAvgDeliveryTime() {
        return delivery_times.average();
    }

    public void resetStats() {
        delivery_times.clear();
    }

    public Object up(Message msg) {
        long start=Util.micros();
        try {
            return up_prot.up(msg);
        }
        finally {
            long time=Util.micros()-start;
            delivery_times.add(time);
        }
    }

    // Dividing the delivery time for a batch by the batch size is problematic, e.g. if a batch of 5 is
    // received at time 0 and the 5 messages are delivered at times 20, 40, 60, 80 and 100, then the total
    // time is 100, divided by 5 is 20 per message. However, this is incorrect as it ignores the waiting
    // times for the individual messages: e.g. message 3 has to wait for 60 until it gets processed.
    // The correct average delivery times would be (20+40+60+80+100)/5 = 60.
    // However, we don't know in up(MessageBatch) when the individual messages are delivered, so we here we
    // can only compute the delivery time of the entire batch
    public void up(MessageBatch batch) {
        // int batch_size=batch.size();
        long start=Util.micros();
        try {
            up_prot.up(batch);
        }
        finally {
            long time=Util.micros()-start;
            //if(batch_size > 1)
              //  time/=batch_size; // cannot use batch.size() as message might have been removed from the batch!
            delivery_times.add(time);
        }
    }
}