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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.protocols;

import org.jgroups.*;
import org.jgroups.annotations.MBean;
import org.jgroups.annotations.Unsupported;
import org.jgroups.stack.Protocol;
import org.jgroups.util.MessageBatch;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.function.Supplier;


/**
 * Example of a protocol layer. Contains no real functionality, can be used as a template.
 */
@Unsupported
@MBean(description="Sample protocol")
public class EXAMPLE extends Protocol {
    final List members=new ArrayList<>();


    /**
     * Just remove if you don't need to reset any state
     */
    public static void reset() {
    }


    public Object down(Event evt) {
        switch(evt.getType()) {
            case Event.TMP_VIEW:
            case Event.VIEW_CHANGE:
                List new_members=((View)evt.getArg()).getMembers();
                synchronized(members) {
                    members.clear();
                    if(new_members != null && !new_members.isEmpty())
                        members.addAll(new_members);
                }
                return down_prot.down(evt);
        }
        return down_prot.down(evt);          // Pass on to the layer below us
    }

    public Object down(Message msg) {
        // Do something with the event, e.g. add a header to the message
        // Optionally pass down
        return down_prot.down(msg);
    }

    public Object up(Message msg) {
        // Do something with the event, e.g. extract the message and remove a header.
        // Optionally pass up
        return up_prot.up(msg);            // Pass up to the layer above us
    }

    public void up(MessageBatch batch) {
        for(Message msg: batch) {
            // do something; perhaps check for the presence of a header
        }
        if(!batch.isEmpty())
            up_prot.up(batch);
    }



    public static class ExampleHeader extends Header {
        // your variables


        public Supplier create() {return ExampleHeader::new;}
        public short getMagicId() {return 21000;}
        public int serializedSize() {
            return 0; // return serialized size of all variables sent across the wire
        }

        public String toString() {
            return "[EXAMPLE:  ]";
        }

        @Override
        public void writeTo(DataOutput out) throws IOException {
            // write variables to stream
        }

        @Override
        public void readFrom(DataInput in) throws IOException, ClassNotFoundException {
            // initialize variables from stream
        }
    }


}