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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.util.ArrayList;
import java.util.List;





/**
 * 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 up(Event evt) {
        switch(evt.getType()) {

            case Event.MSG:
                Message msg=(Message)evt.getArg();
                // Do something with the event, e.g. extract the message and remove a header.
                // Optionally pass up
                break;
        }

        return up_prot.up(evt);            // 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 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);

            case Event.MSG:
                Message msg=(Message)evt.getArg();
                // Do something with the event, e.g. add a header to the message
                // Optionally pass down
                break;
        }

        return down_prot.down(evt);          // Pass on to the layer below us
    }


    public static class ExampleHeader extends Header {
        // your variables

        public int size() {
            return 0; // return serialized size of all variables sent across the wire
        }

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

        public void writeTo(DataOutput out) throws Exception {
            // write variables to stream
        }

        public void readFrom(DataInput in) throws Exception {
            // initialize variables from stream
        }
    }


}