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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.util;

import org.jgroups.Constructable;
import org.jgroups.Global;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.Iterator;
import java.util.NoSuchElementException;
import java.util.function.Supplier;

/**
 * A bitset of missing messages with a fixed size. The index (in the bit set) of a seqno is computed as seqno - offset.
 * @author Bela Ban
 * @since  3.1
 */
public class SeqnoList extends FixedSizeBitSet implements SizeStreamable, Iterable, Constructable {
    protected long offset; // first seqno

    /** Only to be used by serialization */
    public SeqnoList() {
    }

    /**
     * Creates a SeqnoList with a capacity for size elements.
     * @param size The max number of seqnos in the bitset
     * @param offset Lowest seqno. Used to compute the index of a given seqno into the bitset: seqno - offset
     */
    public SeqnoList(int size, long offset) {
        super(size);
        this.offset=offset;
    }

    public Supplier create() {
        return SeqnoList::new;
    }

    public SeqnoList(int size) {
        this(size, 0);
    }

    /** Adds a single seqno */
    public SeqnoList add(long seqno) {
        super.set(index(seqno));
        return this;
    }

    public SeqnoList add(long ... seqnos) {
        if(seqnos != null)
            for(long seqno: seqnos)
                add(seqno);
        return this;
    }

    /** Adds a seqno range */
    public SeqnoList add(long from, long to) {
        super.set(index(from), index(to));
        return this;
    }


    /** Removes all seqnos > seqno */
    public SeqnoList removeHigherThan(long seqno) {
        int from=index(seqno + 1), to=size-1;
        if(from < 0)
            from=0;
        if(from <= to && from >= 0)
            super.clear(from, to);
        return this;
    }

    /** Removes all seqnos < seqno */
    public SeqnoList removeLowerThan(long seqno) {
        int to=index(seqno-1);
        if(to >= 0)
            super.clear(0, to);
        return this;
    }


    /** Returns the last seqno, this is also the highest seqno in the list as we add seqnos in order */
    public long getLast() {
        int index=previousSetBit(size - 1);
        return index == -1? -1 : seqno(index);
    }

    /** Returns the first seqno, this is also the lowest seqno in the list as we add seqnos in order */
    public long getFirst() {
        int index=nextSetBit(0);
        return index < 0? -1 : seqno(index);
    }

    @Override
    public int serializedSize() {
        return Global.INT_SIZE // number of words
          + (words.length+1) * Global.LONG_SIZE; // words + offset
    }

    @Override
    public void writeTo(DataOutput out) throws IOException {
        out.writeInt(size);
        out.writeLong(offset);
        for(long word: words)
            out.writeLong(word);
    }

    @Override
    public void readFrom(DataInput in) throws IOException {
        size=in.readInt();
        offset=in.readLong();
        words=new long[wordIndex(size - 1) + 1];
        for(int i=0; i < words.length; i++)
            words[i]=in.readLong();
    }



    public int size() {
        return super.cardinality();
    }

    public boolean isEmpty() {return cardinality() == 0;}


    public String toString() {
        if(isEmpty())
            return "{}";
        StringBuilder sb=new StringBuilder("(").append(cardinality()).append("): {");

        boolean first=true;
        int num=Util.MAX_LIST_PRINT_SIZE;
        for(int i=nextSetBit(0); i >= 0; i=nextSetBit(i + 1)) {
            int endOfRun=nextClearBit(i);
            if(first)
                first=false;
            else
                sb.append(", ");

            if(endOfRun != -1 && endOfRun-1 != i) {
                sb.append(seqno(i)).append('-').append(seqno(endOfRun-1));
                i=endOfRun;
            }
            else
                sb.append(seqno(i));
            if(--num <= 0) {
                sb.append(", ... ");
                break;
            }
        }

        sb.append('}');
        return sb.toString();
    }

    public Iterator iterator() {
        return new SeqnoListIterator();
    }

    protected int index(long seqno) {return (int)(seqno-offset);}

    protected long seqno(int index) {return offset + index;}


    protected class SeqnoListIterator implements Iterator {
        protected int         index;

        public boolean hasNext() {
            return index < size && nextSetBit(index) != -1;
        }

        public Long next() {
            int next_index=nextSetBit(index);
            if(next_index == -1 || next_index >= size)
                throw new NoSuchElementException("index: " + next_index);
            index=next_index+1;
            return seqno(next_index);
        }

        public void remove() { // not supported
        }
    }
}