Selectable (Qpid Proton-J API)

All Superinterfaces:

Extendable, ReactorChild

All Known Implementing Classes:

SelectableImpl
```
public interface Selectable
extends ReactorChild, Extendable
```
An entity that can be multiplexed using a Selector.
Every selectable is associated with exactly one SelectableChannel. Selectables may be interested in three kinds of events: read events, write events, and timer events. A selectable will express its interest in these events through the isReading(), isWriting(), and getDeadline() methods.
When a read, write, or timer event occurs, the selectable must be notified by calling readable(), writeable(), or expired() as appropriate. Once a selectable reaches a terminal state (see isTerminal(), it will never be interested in events of any kind. When this occurs it should be removed from the Selector and discarded using free().

Nested Class Summary

Nested Classes
Modifier and Type	Interface and Description
`static interface`	`Selectable.Callback` A callback that can be passed to the various "on" methods of the selectable - to allow code to be run when the selectable becomes ready for the associated operation.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`void`	`error()` Notify the selectable that an error has occurred.
`void`	`expired()` Notify the selectable that it has expired.
`void`	`free()` Notify the selectable that it has been free'd.
`java.nio.channels.SelectableChannel`	`getChannel()`
`long`	`getDeadline()`
`Reactor`	`getReactor()`
`boolean`	`isReading()`
`boolean`	`isRegistered()` Check if a selectable is registered.
`boolean`	`isTerminal()`
`boolean`	`isWriting()`
`void`	`onError(Selectable.Callback runnable)` Registers a callback that will be run when the selectable is notified of an error.
`void`	`onExpired(Selectable.Callback runnable)` Registers a callback that will be run when the selectable expires.
`void`	`onFree(Selectable.Callback runnable)` Registers a callback that will be run when the selectable is notified that it has been free'd.
`void`	`onReadable(Selectable.Callback runnable)` Registers a callback that will be run when the selectable becomes ready for reading.
`void`	`onRelease(Selectable.Callback runnable)` Registers a callback that will be run when the selectable is notified that it has been released.
`void`	`onWritable(Selectable.Callback runnable)` Registers a callback that will be run when the selectable becomes ready for writing.
`void`	`readable()` Notify the selectable that the underlying `SelectableChannel` is ready for a read operation.
`void`	`release()` Notify the selectable that it has been released.
`void`	`setChannel(java.nio.channels.SelectableChannel channel)` Associates a `SelectableChannel` with this selector.
`void`	`setCollector(Collector collector)` Configure a selectable with a set of callbacks that emit readable, writable, and expired events into the supplied collector.
`void`	`setDeadline(long deadline)` Sets the value that will be returned by `getDeadline()`.
`void`	`setReading(boolean reading)` Sets the value that will be returned by `isReading()`.
`void`	`setRegistered(boolean registered)` Set the registered flag for a selectable.
`void`	`setWriting(boolean writing)` Sets the value that will be returned by `isWriting()`.
`void`	`terminate()` Terminates the selectable.
`void`	`writeable()` Notify the selectable that the underlying `SelectableChannel` is ready for a write operation.

Methods inherited from interface org.apache.qpid.proton.engine.Extendable
attachments

- Method Detail
  - isReading
```
boolean isReading()
```
    Returns:
    
    true if the selectable is interested in receiving notification (via the readable() method that indicate that the associated SelectableChannel has data ready to be read from it.
  - isWriting
```
boolean isWriting()
```
    Returns:
    
    true if the selectable is interested in receiving notifications (via the writeable() method that indicate that the associated SelectableChannel is ready to be written to.
  - getDeadline
```
long getDeadline()
```
    Returns:
    
    a deadline after which this selectable can expect to receive a notification (via the expired() method that indicates that the deadline has past. The deadline is expressed in the same format as System.currentTimeMillis(). Returning a deadline of zero (or a negative number) indicates that the selectable does not wish to be notified of expiry.
  - setReading
```
void setReading(boolean reading)
```
    Sets the value that will be returned by isReading().
    
    Parameters:
    
    reading -
  - setWriting
```
void setWriting(boolean writing)
```
    Sets the value that will be returned by isWriting().
    
    Parameters:
    
    writing -
  - setDeadline
```
void setDeadline(long deadline)
```
    Sets the value that will be returned by getDeadline().
    
    Parameters:
    
    deadline -
  - onReadable
```
void onReadable(Selectable.Callback runnable)
```
    Registers a callback that will be run when the selectable becomes ready for reading.
    
    Parameters:
    
    runnable - the callback to register. Any previously registered callback will be replaced.
  - onWritable
```
void onWritable(Selectable.Callback runnable)
```
    Registers a callback that will be run when the selectable becomes ready for writing.
    
    Parameters:
    
    runnable - the callback to register. Any previously registered callback will be replaced.
  - onExpired
```
void onExpired(Selectable.Callback runnable)
```
    Registers a callback that will be run when the selectable expires.
    
    Parameters:
    
    runnable - the callback to register. Any previously registered callback will be replaced.
  - onError
```
void onError(Selectable.Callback runnable)
```
    Registers a callback that will be run when the selectable is notified of an error.
    
    Parameters:
    
    runnable - the callback to register. Any previously registered callback will be replaced.
  - onRelease
```
void onRelease(Selectable.Callback runnable)
```
    Registers a callback that will be run when the selectable is notified that it has been released.
    
    Parameters:
    
    runnable - the callback to register. Any previously registered callback will be replaced.
  - onFree
```
void onFree(Selectable.Callback runnable)
```
    Registers a callback that will be run when the selectable is notified that it has been free'd.
    
    Parameters:
    
    runnable - the callback to register. Any previously registered callback will be replaced.
  - readable
```
void readable()
```
    Notify the selectable that the underlying SelectableChannel is ready for a read operation.
  - writeable
```
void writeable()
```
    Notify the selectable that the underlying SelectableChannel is ready for a write operation.
  - expired
```
void expired()
```
    Notify the selectable that it has expired.
  - error
```
void error()
```
    Notify the selectable that an error has occurred.
  - release
```
void release()
```
    Notify the selectable that it has been released.
  - free
```
void free()
```
    Notify the selectable that it has been free'd.
    
    Specified by:
    
    free in interface ReactorChild
  - setChannel
```
void setChannel(java.nio.channels.SelectableChannel channel)
```
    Associates a SelectableChannel with this selector.
    
    Parameters:
    
    channel -
  - getChannel
```
java.nio.channels.SelectableChannel getChannel()
```
    Returns:
    
    the SelectableChannel associated with this selector.
  - isRegistered
```
boolean isRegistered()
```
    Check if a selectable is registered. This can be used for tracking whether a given selectable has been registerd with an external event loop.
    Note: the reactor code, currently, does not use this flag.
    
    Returns:
    
    trueif the selectable is registered.
  - setRegistered
```
void setRegistered(boolean registered)
```
    Set the registered flag for a selectable.
    Note: the reactor code, currently, does not use this flag.
    
    Parameters:
    
    registered - the value returned by isRegistered()
  - setCollector
```
void setCollector(Collector collector)
```
    Configure a selectable with a set of callbacks that emit readable, writable, and expired events into the supplied collector.
    
    Parameters:
    
    collector -
  - getReactor
```
Reactor getReactor()
```
    Returns:
    
    the reactor to which this selectable is a child.
  - terminate
```
void terminate()
```
    Terminates the selectable. Once a selectable reaches a terminal state it will never be interested in events of any kind.
  - isTerminal
```
boolean isTerminal()
```
    Returns:
    
    true if the selectable has reached a terminal state.

Interface Selectable

Nested Class Summary

Method Summary

Methods inherited from interface org.apache.qpid.proton.engine.Extendable

Method Detail

isReading

isWriting

getDeadline

setReading

setWriting

setDeadline

onReadable

onWritable

onExpired

onError

onRelease

onFree

readable

writeable

expired

error

release

free

setChannel

getChannel

isRegistered

setRegistered

setCollector

getReactor

terminate

isTerminal