code: private static void deliverEvent(final NextFilter nextFilter,
              final IoSession session, final IoSessionEventType type,
              final IdleStatus status) {
          switch (type) {
          case CREATED:
              nextFilter.sessionCreated(session);
              break;
          case OPENED:
              nextFilter.sessionOpened(session);
              break;
          case IDLE:
              nextFilter.sessionIdle(session, status);
              break;
          case CLOSED:
              nextFilter.sessionClosed(session);
              break;
          }
      }
docs: Static method which effectively delivers the specified event to the next filter
  <code>nextFilter</code> on the <code>session</code>.
  
  @param nextFilter the next filter
  @param session the session on which the event occured
  @param type the event type
  @param status the idle status should only be non null only if the event type is
  {@link IoSessionEventType#IDLE}