Emitter (MicroProfile Reactive Streams Messaging Implementation 2.0.1 API)

Type Parameters:

T - type of payload or Message.

All Known Implementing Classes:

EmitterImpl
```
public interface Emitter<T>
```
Interface used to feed a stream from an imperative piece of code.
Instances are injected using:
```
 @Inject
 @Channel("my-channel")
 Emitter<String> emitter;
 
```
You can inject emitter sending payload or Messages.
The name of the channel (given in the Channel annotation) indicates which streams is fed. It must match the name used in a method using @Incoming or an outgoing stream configured in the application configuration.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`complete()`	Sends the completion event to the channel indicating that no other events will be sent afterward.
`void`	`error(Exception e)`	Sends a failure event to the channel.
`boolean`	`isCancelled()`
`boolean`	`isRequested()`
`<M extends Message<? extends T>> void`	`send(M msg)`	Sends a payload to the channel.
`CompletionStage<Void>`	`send(T msg)`	Sends a payload to the channel.

- Method Detail
  - send
```
CompletionStage<Void> send(T msg)
```
    Sends a payload to the channel.
    
    Parameters:
    
    msg - the thing to send, must not be null
    
    Returns:
    
    the CompletionStage, which will be completed as sending the payload alone does not provide a callback mechanism.
    
    Throws:
    
    IllegalStateException - if the channel has been canceled or terminated.
  - send
```
<M extends Message<? extends T>> void send(M msg)
```
    Sends a payload to the channel.
    
    Type Parameters:
    
    M - the Message type
    
    Parameters:
    
    msg - the Message to send, must not be null
    
    Throws:
    
    IllegalStateException - if the channel has been canceled or terminated.
  - complete
```
void complete()
```
    Sends the completion event to the channel indicating that no other events will be sent afterward.
  - error
```
void error(Exception e)
```
    Sends a failure event to the channel. No more events will be sent afterward.
    
    Parameters:
    
    e - the exception, must not be null
  - isCancelled
```
boolean isCancelled()
```
    Returns:
    
    true if the emitter has been terminated or the subscription cancelled.
  - isRequested
```
boolean isRequested()
```
    Returns:
    
    true if the subscriber accepts messages, false otherwise. Using send(Object) on an emitter not expecting message would throw an IllegalStateException.