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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.Address;
import org.jgroups.Event;
import org.jgroups.View;
import org.jgroups.stack.Protocol;
import org.jgroups.util.Tuple;

import javax.crypto.SecretKey;
import java.util.Arrays;
import java.util.List;

/**
 * Base class for protocols implementing key exchange: a secret key to be used for encryption is exchanged between
 * 2 parties (usually the key server and a new cluster member) securely; ie. without the possibility of
 * man-in-the-middle attacks, compromising the key and (optional) perfect forward secrecy.

 * This protocol has to be placed somewhere below {@link ASYM_ENCRYPT}.
 * @author Bela Ban
 * @since  4.0.5
 */
public abstract class KeyExchange extends Protocol {

    public List requiredUpServices() {
        return Arrays.asList(Event.GET_SECRET_KEY, Event.SET_SECRET_KEY);
    }

    /**
     * Needs to fetch the secret key from a given destination (usually the key server). When received, the secret key
     * (and version) needs to be installed in a protocol above using {@link #setSecretKeyAbove(Tuple)}.
     * @param target The member from which to fetch the secret key
     */
    public abstract void fetchSecretKeyFrom(Address target) throws Exception;

    /** Returns the address of the server, e.g. server socket (if any) */
    public abstract Address getServerLocation();


    public Object down(Event evt) {
        switch(evt.type()) {
            case Event.VIEW_CHANGE:
                handleView(evt.arg());
                break;
        }
        return down_prot.down(evt);
    }

    protected void handleView(View view) {}

    /** Fetches the secret key from a protocol above us
     * @return The secret key and its version
     */
    protected Tuple getSecretKeyFromAbove() {
        return (Tuple)up_prot.up(new Event(Event.GET_SECRET_KEY));
    }

    /** Sets the secret key in a protocol above us
     * @param key The secret key and its version
     */
    protected void setSecretKeyAbove(Tuple key) {
        up_prot.up(new Event(Event.SET_SECRET_KEY, key));
    }

    protected  T findProtocolAbove(Class clazz) {
        Protocol tmp=this;
        while(tmp != null) {
            Class protClass=tmp.getClass();
            if(clazz.isAssignableFrom(protClass))
                return (T)tmp;
            tmp=tmp.getUpProtocol();
        }
        return null;
    }

}