public  void addPhaseListener(PhaseListener listener) 
{
        if (listener == null) {
            throw new NullPointerException
                  (MessageUtils.getExceptionMessageString
                        (MessageUtils.NULL_PARAMETERS_ERROR_MESSAGE_ID, "listener"));
        }
        if (listeners == null) {
            listeners = new CopyOnWriteArrayList< PhaseListener >();
        }
        if (listeners.contains(listener)) {
            if (LOGGER.isLoggable(Level.FINE)) {
                LOGGER.log(Level.FINE,
                           "jsf.lifecycle.duplicate_phase_listener_detected",
                           listener.getClass().getName());
            }
        } else {
            if (LOGGER.isLoggable(Level.FINE)) {
                LOGGER.log(Level.FINE,
                           "addPhaseListener({0},{1})",
                           new Object[]{
                                 listener.getPhaseId().toString(),
                                 listener.getClass().getName()});
            }
            listeners.add(listener);
        }
}

 public  void execute(FacesContext context) throws FacesException 
{
        
    // ------------------------------------------------------- Lifecycle Methods
    // Execute the phases up to but not including Render Response
        if (context == null) {
            throw new NullPointerException
                (MessageUtils.getExceptionMessageString
                 (MessageUtils.NULL_PARAMETERS_ERROR_MESSAGE_ID, "context"));
        }
        if (LOGGER.isLoggable(Level.FINE)) {
            LOGGER.fine("execute(" + context + ")");
        }
        for (int i = 1, len = phases.length -1 ; i <  len; i++) { // Skip ANY_PHASE placeholder
            if (context.getRenderResponse() ||
                context.getResponseComplete()) {
                break;
            }
            phases[i].doPhase(context, this, listeners.listIterator());
        }
}

 public PhaseListener[] getPhaseListeners() 
{
        return listeners.toArray(new PhaseListener[listeners.size()]);
}

 public  void removePhaseListener(PhaseListener listener) 
{
        if (listener == null) {
            throw new NullPointerException
                  (MessageUtils.getExceptionMessageString
                        (MessageUtils.NULL_PARAMETERS_ERROR_MESSAGE_ID, "listener"));
        }
        if (listeners.remove(listener) && LOGGER.isLoggable(Level.FINE)) {
            LOGGER.log(Level.FINE,
                       "removePhaseListener({0})",
                       new Object[]{listener.getClass().getName()});
        }
}

 public  void render(FacesContext context) throws FacesException 
{
        if (context == null) {
            throw new NullPointerException
                (MessageUtils.getExceptionMessageString
                 (MessageUtils.NULL_PARAMETERS_ERROR_MESSAGE_ID, "context"));
        }
        if (LOGGER.isLoggable(Level.FINE)) {
            LOGGER.fine("render(" + context + ")");
        }
        if (!context.getResponseComplete()) {
            response.doPhase(context, this, listeners.listIterator());
        }
}