* {@code new FIFOEntry(anEntry)} instead of a plain entry object.
 *
 * <pre>{@code
 * class FIFOEntry<E extends Comparable<? super E>> implements Comparable<FIFOEntry<E>> {
 *   static final AtomicLong seq = new AtomicLong();
 *
 *   final long seqNum;
 *   final E entry;
 *
 *   public FIFOEntry(E entry) {
 *     seqNum = seq.getAndIncrement();
 *     this.entry = entry;