Class Channels

java.lang.Object

jdk.nio.Channels

public final class Channels extends Object

Defines static methods to create channels.

Unless otherwise specified, passing a null argument to any of the methods defined here will cause a NullPointerException to be thrown.

Since:: 11

Nested Class Summary

Modifier and Type	Class	Description
`static interface`	`Channels.SelectableChannelCloser`	An object used to coordinate the closing of a selectable channel created by `readWriteSelectableChannel`.

Method Summary

Modifier and Type	Method	Description
`static SelectableChannel`	`readWriteSelectableChannel(FileDescriptor fd, Channels.SelectableChannelCloser closer)`	Creates a selectable channel to a file descriptor that supports an `operation-set` of `OP_READ` and `OP_WRITE`.

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.

Method Details

readWriteSelectableChannel

public static SelectableChannel readWriteSelectableChannel(FileDescriptor fd, Channels.SelectableChannelCloser closer)

Creates a selectable channel to a file descriptor that supports an operation-set of OP_READ and OP_WRITE. The selectable channel will be created by the default SelectorProvider.

The given file descriptor is a socket or resource that can be multiplexed by a Selector for read and write readiness. Great care is required to coordinate direct use of the file descriptor with the use of the selectable channel. In particular, changing the blocking mode or closing the file descriptor without careful coordination will result in unspecified and unsafe side effects. The given SelectableChannelCloser is invoked to close the file descriptor and to coordinate the closing when the channel is registered with a Selector.

Implementation Note:: This method throws UnsupportedOperationException if the default SelectorProvider is not the JDK built-in implementation.
Parameters:: fd - The file descriptor; closer - The object to close the channel
Returns:: The selectable channel
Throws:: IllegalArgumentException - If the file descriptor is not valid

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