Added in API level 1

Channel

interface Channel : Closeable
java.nio.channels.Channel

A nexus for I/O operations.

A channel represents an open connection to an entity such as a hardware device, a file, a network socket, or a program component that is capable of performing one or more distinct I/O operations, for example reading or writing.

A channel is either open or closed. A channel is open upon creation, and once closed it remains closed. Once a channel is closed, any attempt to invoke an I/O operation upon it will cause a ClosedChannelException to be thrown. Whether or not a channel is open may be tested by invoking its isOpen method.

Channels are, in general, intended to be safe for multithreaded access as described in the specifications of the interfaces and classes that extend and implement this interface.

Summary

Public methods
abstract Unit

Closes this channel.

abstract Boolean

Tells whether or not this channel is open.

Public methods

close

Added in API level 1
abstract fun close(): Unit

Closes this channel.

After a channel is closed, any further attempt to invoke I/O operations upon it will cause a ClosedChannelException to be thrown.

If this channel is already closed then invoking this method has no effect.

This method may be invoked at any time. If some other thread has already invoked it, however, then another invocation will block until the first invocation is complete, after which it will return without effect.

Exceptions
java.lang.Exception if this resource cannot be closed
java.io.IOException If an I/O error occurs

isOpen

Added in API level 1
abstract fun isOpen(): Boolean

Tells whether or not this channel is open.

Return
Boolean true if, and only if, this channel is open