code: public boolean startSsl(IoSession session) throws SSLException {
          SslHandler handler = getSslSessionHandler(session);
          boolean started;
          synchronized (handler) {
              if (handler.isOutboundDone()) {
                  NextFilter nextFilter = (NextFilter) session
                          .getAttribute(NEXT_FILTER);
                  handler.destroy();
                  handler.init();
                  handler.handshake(nextFilter);
                  started = true;
              } else {
                  started = false;
              }
          }
  
          handler.flushScheduledEvents();
          return started;
      }
docs: (Re)starts SSL session for the specified <tt>session</tt> if not started yet.
  Please note that SSL session is automatically started by default, and therefore
  you don't need to call this method unless you've used TLS closure.
  
  @return <tt>true</tt> if the SSL session has been started, <tt>false</tt> if already started.
  @throws SSLException if failed to start the SSL session