SubscribableChannel (Spring Framework 5.2.12.RELEASE API)

All Superinterfaces:
MessageChannel
All Known Implementing Classes:
AbstractSubscribableChannel, ExecutorSubscribableChannel
```
public interface SubscribableChannel
extends MessageChannel
```
A MessageChannel that maintains a registry of subscribers and invokes them to handle messages sent through this channel.
Since:
4.0
Author:
Mark Fisher

Field Summary
- Fields inherited from interface org.springframework.messaging.MessageChannel
  INDEFINITE_TIMEOUT

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`boolean`	`subscribe(MessageHandler handler)`	Register a message handler.
`boolean`	`unsubscribe(MessageHandler handler)`	Un-register a message handler.

Methods inherited from interface org.springframework.messaging.MessageChannel
send, send

- Method Detail
  - subscribe
```
boolean subscribe(MessageHandler handler)
```
    Register a message handler.
    Returns:
    true if the handler was subscribed or false if it was already subscribed.
  - unsubscribe
```
boolean unsubscribe(MessageHandler handler)
```
    Un-register a message handler.
    Returns:
    true if the handler was un-registered, or false if was not registered.