*
     * @param contextHandle the context handle from registration
     * @param sequenceNumber the sequence number for this heartbeat
     */
    public WitnessHeartbeatMessage(byte[] contextHandle, long sequenceNumber) {
        super(WITNESS_HEARTBEAT);
        this.contextHandle = contextHandle != null ? contextHandle.clone() : new byte[20];
        this.sequenceNumber = sequenceNumber;

     * @return the context handle
     */
    public byte[] getContextHandle() {
        return contextHandle;
    }

    /**
     * Sets the context handle.
     *
     * @param contextHandle the context handle
     */
    public void setContextHandle(byte[] contextHandle) {
        this.contextHandle = contextHandle;
    }

     *
     * @param contextHandle the context handle from registration
     */
    public WitnessUnregisterMessage(byte[] contextHandle) {
        super(WITNESS_UNREGISTER);
        this.contextHandle = contextHandle != null ? contextHandle.clone() : new byte[20];
    }

    /**
     * Sets the context handle for unregistration.
     *
     * @param contextHandle the context handle from registration
     */

     * Generates a registration ID from context handle and share name.
     *
     * @param contextHandle the context handle
     * @param shareName the share name
     * @return the registration ID
     */
    private String generateRegistrationId(byte[] contextHandle, String shareName) {
        if (contextHandle == null || contextHandle.length == 0) {
            return "WITNESS-" + System.currentTimeMillis() + "-" + shareName.hashCode();

     * @return the context handle
     */
    public byte[] getContextHandle() {
        return contextHandle;
    }

    /**
     * Sets the context handle.
     *
     * @param contextHandle the context handle
     */
    public void setContextHandle(byte[] contextHandle) {
        this.contextHandle = contextHandle;
    }

     *
     * @return the context handle
     */
    public byte[] getContextHandle() {
        return contextHandle;
    }

    /**
     * Sets the context handle.
     *
     * @param contextHandle the context handle
     */
    public void setContextHandle(byte[] contextHandle) {
        this.contextHandle = contextHandle;
    }

     *
     * @return the context handle
     */
    public byte[] getContextHandle() {
        return contextHandle;
    }

    /**
     * Sets the context handle.
     *
     * @param contextHandle the context handle
     */
    public void setContextHandle(byte[] contextHandle) {
        this.contextHandle = contextHandle;
    }

     *
     * @param contextHandle the context handle from registration
     */
    public void setContextHandle(byte[] contextHandle) {
        this.contextHandle = contextHandle != null ? contextHandle.clone() : null;
    }

    /**
     * Gets the context handle.
     *
     * @return the context handle
     */
    public byte[] getContextHandle() {
        return contextHandle != null ? contextHandle.clone() : null;

     */
    public byte[] getContextHandle() {
        return contextHandle != null ? contextHandle.clone() : null;
    }

    /**
     * Sets the context handle.
     *
     * @param contextHandle the context handle
     */
    public void setContextHandle(byte[] contextHandle) {
        this.contextHandle = contextHandle != null ? contextHandle.clone() : null;
    }

    @Override

        String registrationId = registration.getRegistrationId();

        CompletableFuture<Void> asyncTask = CompletableFuture.runAsync(() -> {
            byte[] contextHandle = registration.getContextHandle();

            while (!Thread.currentThread().isInterrupted() && registrations.containsKey(registrationId)