org.jgroups.protocols.tom.SequenceNumberManager Maven / Gradle / Ivy
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;
}
}