Class AbstractSelectionKey

java.lang.Object

java.nio.channels.SelectionKey

java.nio.channels.spi.AbstractSelectionKey

public abstract class AbstractSelectionKey extends SelectionKey

Base implementation class for selection keys.

This class tracks the validity of the key and implements cancellation.

Since:: 1.4

Field Summary

Fields declared in class SelectionKey

OP_ACCEPT, OP_CONNECT, OP_READ, OP_WRITE

Modifier and Type	Field	Description
`static final int`	`OP_ACCEPT`	Operation-set bit for socket-accept operations.
`static final int`	`OP_CONNECT`	Operation-set bit for socket-connect operations.
`static final int`	`OP_READ`	Operation-set bit for read operations.
`static final int`	`OP_WRITE`	Operation-set bit for write operations.

Constructor Summary

AbstractSelectionKey()

Modifier	Constructor	Description
`protected`	Initializes a new instance of this class.

Method Summary

Modifier and Type	Method	Description
`final void`	`cancel()`	Cancels this key.
`final boolean`	`isValid()`	Tells whether or not this key is valid.

Methods declared in class SelectionKey

attach, attachment, channel, interestOps, interestOps, interestOpsAnd, interestOpsOr, isAcceptable, isConnectable, isReadable, isWritable, readyOps, selector

Modifier and Type	Method	Description
`final Object`	`attach(Object ob)`	Attaches the given object to this key.
`final Object`	`attachment()`	Retrieves the current attachment.
`abstract SelectableChannel`	`channel()`	Returns the channel for which this key was created.
`abstract int`	`interestOps()`	Retrieves this key's interest set.
`abstract SelectionKey`	`interestOps(int ops)`	Sets this key's interest set to the given value.
`int`	`interestOpsAnd(int ops)`	Atomically sets this key's interest set to the bitwise intersection ("and") of the existing interest set and the given value.
`int`	`interestOpsOr(int ops)`	Atomically sets this key's interest set to the bitwise union ("or") of the existing interest set and the given value.
`final boolean`	`isAcceptable()`	Tests whether this key's channel is ready to accept a new socket connection.
`final boolean`	`isConnectable()`	Tests whether this key's channel has either finished, or failed to finish, its socket-connection operation.
`final boolean`	`isReadable()`	Tests whether this key's channel is ready for reading.
`final boolean`	`isWritable()`	Tests whether this key's channel is ready for writing.
`abstract int`	`readyOps()`	Retrieves this key's ready-operation set.
`abstract Selector`	`selector()`	Returns the selector for which this key was created.

Methods declared in class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()`	Returns a string representation of the object.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

AbstractSelectionKey

protected AbstractSelectionKey()

Initializes a new instance of this class.

Method Details

isValid

public final boolean isValid()

Description copied from class: SelectionKey

Tells whether or not this key is valid.

A key is valid upon creation and remains so until it is cancelled, its channel is closed, or its selector is closed.

Specified by:: isValid in class SelectionKey
Returns:: true if, and only if, this key is valid

cancel

public final void cancel()

Cancels this key.

If this key has not yet been cancelled then it is added to its selector's cancelled-key set while synchronized on that set.

Specified by:: cancel in class SelectionKey

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