var cancel context.CancelFunc
		ctx, cancel = context.WithTimeout(ctx, defaultSingleRequestTimeout)
		defer cancel()
	}
	// Send request
	if err := m.send(msg); err != nil {
		return nil, err
	}
	if debugReqs {
		fmt.Println(m.MuxID, m.parent.String(), "SEND")
	}
	// Wait for response or context.
	select {
	case v, ok := <-ch:
		if !ok {
			return nil, ErrDisconnected
		}

    /**
     * @return true if the <b>debug</b> error level is enabled
     */
    boolean isDebugEnabled();

    /**
     * Send a message to the user in the <b>debug</b> error level.
     *
     * @param content
     */
    void debug(CharSequence content);

    /**
     * Send a message (and accompanying exception) to the user in the <b>debug</b> error level.<br>

	go func() {
		wg.Wait()
		defer xioutil.SafeClose(send)
		err := m.handleRequests(ctx, msg, send, handler, handlerIn)
		if err != nil {
			handlerErr.Store(err)
		}
	}()

	// Response sender goroutine...
	go func(outBlock <-chan struct{}) {
		wg.Wait()
		defer m.parent.deleteMux(true, m.ID)
		m.sendResponses(ctx, send, c, &handlerErr, outBlock)
	}(m.outBlock)

import org.dbflute.mail.send.SMailDeliveryDepartment;
import org.dbflute.mail.send.SMailPostalMotorbike;
import org.dbflute.mail.send.SMailPostalParkingLot;
import org.dbflute.mail.send.SMailPostalPersonnel;
import org.dbflute.mail.send.embedded.personnel.SMailDogmaticPostalPersonnel;
import org.dbflute.mail.send.embedded.receptionist.SMailConventionReceptionist;
import org.dbflute.mail.send.supplement.async.SMailAsyncStrategy;

///

## Await for messages and send messages

In your WebSocket route you can `await` for messages and send messages.

```Python hl_lines="48-52"
{!../../docs_src/websockets/tutorial001.py!}
```

You can receive and send binary, text, and JSON data.

## Try it

If your file is named `main.py`, run your application with:

    server.send(message3)
    clientListener.assertTextMessage(message3)

    // Empty client to server message.
    val message4 = ""
    client.send(message4)
    serverListener.assertTextMessage(message4)

    // Server to client message that shares context with message1.
    val message5 = message1 + message1
    server.send(message5)
    clientListener.assertTextMessage(message5)

    And this path operation will:

    * Send the invoice to the client.
    * Collect the money from the client.
    * Send a notification back to the API user (the external developer), as a callback.
        * At this point is that the API will somehow send a POST request to the
            external API with the notification of the invoice event
            (e.g. "payment successful").
    """

import org.codelibs.fess.util.ComponentUtil;
import org.dbflute.mail.CardView;
import org.dbflute.mail.send.supplement.SMailPostingDiscloser;

public class NotificationHelper {
    private static final Logger logger = LogManager.getLogger(NotificationHelper.class);

    protected static final char LF = '\n';

    public void send(final CardView cardView, final SMailPostingDiscloser discloser) {
        sendToSlack(cardView, discloser);

                            tree.send(new SmbComClose(sess.getConfig(), resp2.getFid(), 0L));
                        }
                    }
                }
                finally {
                    if ( resp != null && !trans.isDisconnected() ) {
                        tree.send(new SmbComClose(sess.getConfig(), resp.getFid(), 0L));
                    }
                }

	for k, v := range list.targets {
		ntargets[k] = v
	}
	return ntargets
}

// Send - sends events to targets identified by target IDs.
func (list *TargetList) Send(event Event, id TargetID) (*http.Response, error) {
	list.RLock()
	target, ok := list.targets[id]
	list.RUnlock()
	if ok {
		return target.Send(event)
	}
	return nil, ErrARNNotFound{}
}

// Stats returns stats for targets.