Uses of Class java.nio.channels.SelectionKey (Java Platform SE 8 )
Date: 2026-04-17

## 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 and 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 and Description
    --- | ---
    `abstract Set<SelectionKey>` | Selector.`keys()` Returns this selector's key set.
    `abstract Set<SelectionKey>` | Selector.`selectedKeys()` Returns this selector's selected-key set.

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

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

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

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

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