Uses of Class java.nio.channels.SelectionKey (Java SE 12 & JDK 12 )

## Uses of Class
java.nio.channels.SelectionKey

- Packages that use SelectionKey
  Package | Description
  --- | ---
  java.nio.channels | Defines channels, which represent connections to entities that are capable of performing I/O operations, such as files and sockets; defines selectors, for multiplexed, non-blocking I/O operations.
  java.nio.channels.spi | Service-provider classes for the `java.nio.channels` package.

- - ### Uses of SelectionKey in java.nio.channels

    Methods in java.nio.channels that return SelectionKey
    Modifier and Type | Method | Description
    --- | --- | ---
    `abstract SelectionKey` | SelectionKey.`interestOps​(int ops)` | Sets this key's interest set to the given value.
    `abstract SelectionKey` | SelectableChannel.`keyFor​(Selector sel)` | Retrieves the key representing the channel's registration with the given selector.
    `SelectionKey` | SelectableChannel.`register​(Selector sel, int ops)` | Registers this channel with the given selector, returning a selection key.
    `abstract SelectionKey` | SelectableChannel.`register​(Selector sel, int ops, Object att)` | Registers this channel with the given selector, returning a selection key.

    Methods in java.nio.channels that return types with arguments of type SelectionKey
    Modifier and Type | Method | Description
    --- | --- | ---
    `abstract Set<SelectionKey>` | Selector.`keys()` | Returns this selector's key set.
    `abstract Set<SelectionKey>` | Selector.`selectedKeys()` | Returns this selector's selected-key set.

    Method parameters in java.nio.channels with type arguments of type SelectionKey
    Modifier and Type | Method | Description
    --- | --- | ---
    `int` | Selector.`select​(Consumer<SelectionKey> action)` | Selects and performs an action on the keys whose corresponding channels are ready for I/O operations.
    `int` | Selector.`select​(Consumer<SelectionKey> action, long timeout)` | Selects and performs an action on the keys whose corresponding channels are ready for I/O operations.
    `int` | Selector.`selectNow​(Consumer<SelectionKey> action)` | Selects and performs an action on the keys whose corresponding channels are ready for I/O operations.

  - ### Uses of SelectionKey in java.nio.channels.spi

    Subclasses of SelectionKey in java.nio.channels.spi
    Modifier and Type | Class | Description
    --- | --- | ---
    `class` | `AbstractSelectionKey` | Base implementation class for selection keys.

    Methods in java.nio.channels.spi that return SelectionKey
    Modifier and Type | Method | Description
    --- | --- | ---
    `SelectionKey` | AbstractSelectableChannel.`register​(Selector sel, int ops, Object att)` | Registers this channel with the given selector, returning a selection key.
    `protected abstract SelectionKey` | AbstractSelector.`register​(AbstractSelectableChannel ch, int ops, Object att)` | Registers the given channel with this selector.

    Methods in java.nio.channels.spi that return types with arguments of type SelectionKey
    Modifier and Type | Method | Description
    --- | --- | ---
    `protected Set<SelectionKey>` | AbstractSelector.`cancelledKeys()` | Retrieves this selector's cancelled-key set.