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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.tom;

/**
 * Manages the messages sequence number (keeps it up-to-date)
 *
 * @author Pedro Ruivo
 * @since 3.1
 */
public class SequenceNumberManager {

    private long sequenceNumber = 0;

    /**
     * 
     * @return the next sequence number
     */
    public long getAndIncrement() {
        return sequenceNumber++;
    }

    /**
     * updates the sequence number to the maximum between them
     * @param otherSequenceNumber   the sequence number received
     */
    public void update(long otherSequenceNumber) {
        sequenceNumber = Math.max(sequenceNumber, otherSequenceNumber + 1);
    }

    /**
     * updates the sequence number and returns the next, that will be used a propose sequence number 
     * @param otherSequenceNumber   the sequence number received
     * @return                      the next sequence number or the received sequence number, if the received sequence
     *                              number is higher the the actual sequence number
     */
    public long updateAndGet(long otherSequenceNumber) {
        if (sequenceNumber >= otherSequenceNumber) {
            return sequenceNumber++;
        } else {
            sequenceNumber = otherSequenceNumber + 1;
            return otherSequenceNumber;
        }
    }

    public long get() {
        return sequenceNumber;
    }
}