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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;

import org.jgroups.util.Bits;
import org.jgroups.util.Streamable;
import org.jgroups.util.Util;

import java.io.DataInput;
import java.io.DataOutput;


/**
 * ViewIds are used for ordering views (each view has a ViewId and a list of members).
 * Ordering between views is important for example in a virtual synchrony protocol where
 * all views seen by a member have to be ordered.
 */
public class ViewId implements Comparable, Streamable {
    protected Address creator;   // Address of the creator of this view
    protected long    id=0;      // Lamport time of the view


    public ViewId() { // used for externalization
    }


    /**
     * Creates a ViewID with the coordinator address and a Lamport timestamp of 0.
     *
     * @param creator the address of the member that issued this view
     */
    public ViewId(Address creator) {
        this.creator=creator;
        if(this.creator == null)
            throw new IllegalArgumentException("creator cannot be null");
    }

    /**
     * Creates a ViewID with the coordinator address and the given Lamport timestamp.
     *
     * @param creator - the address of the member that issued this view
     * @param id         - the Lamport timestamp of the view
     */
    public ViewId(Address creator, long id) {
        this(creator);
        this.id=id;
    }


    /**
     * Returns the address of the member that issued this view
     *
     * @return the Address of the the creator
     */
    public Address getCreator() {
        return creator;
    }

    /**
     * returns the lamport time of the view
     *
     * @return the lamport time timestamp
     */
    public long getId() {
        return id;
    }

    public String toString() {
        return "[" + creator + '|' + id + ']';
    }


    public ViewId copy() {
        return new ViewId(creator, id);
    }

    /**
     * Establishes an order between 2 ViewIds. The comparison is done on the IDs, if they are equal, we use the creator.
     *
     * @return 0 for equality, value less than 0 if smaller, greater than 0 if greater.
     */
    public int compareTo(ViewId other) {
        return id > other.id ? 1 : id < other.id ? -1 : creator.compareTo(other.creator);
    }

    /**
     * Establishes an order between 2 ViewIds. Note that we compare only on IDs !
     *
     * @return 0 for equality, value less than 0 if smaller, greater than 0 if greater.
     */
    public int compareToIDs(ViewId other) {
        return id > other.id ? 1 : id < other.id ? -1 : 0;
    }


    public boolean equals(Object other) {
        return other instanceof ViewId && (this == other  || compareTo((ViewId)other) == 0);
    }


    public int hashCode() {
        return (int)(creator.hashCode() + id);
    }


    public void writeTo(DataOutput out) throws Exception {
        Util.writeAddress(creator, out);
        Bits.writeLong(id,out);
    }

    public void readFrom(DataInput in) throws Exception {
        creator=Util.readAddress(in);
        id=Bits.readLong(in);
    }

    public int serializedSize() {
        return Bits.size(id) + Util.size(creator);
    }

}