Module java.base

Package java.nio.channels

Interface Channel

All Superinterfaces:

AutoCloseable, Closeable

All Known Subinterfaces:

AsynchronousByteChannel, AsynchronousChannel, ByteChannel, GatheringByteChannel, InterruptibleChannel, MulticastChannel, NetworkChannel, ReadableByteChannel, ScatteringByteChannel, SeekableByteChannel, WritableByteChannel

All Known Implementing Classes:

AbstractInterruptibleChannel, AbstractSelectableChannel, AsynchronousFileChannel, AsynchronousServerSocketChannel, AsynchronousSocketChannel, DatagramChannel, FileChannel, Pipe.SinkChannel, Pipe.SourceChannel, SctpChannel, SctpMultiChannel, SctpServerChannel, SelectableChannel, ServerSocketChannel, SocketChannel

public interface Channel
extends Closeable

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.

Since:

1.4

Method Summary

Modifier and Type	Method	Description
void	close()	Closes this channel.
boolean	isOpen()	Tells whether or not this channel is open.

Method Detail

isOpen

boolean isOpen()

Tells whether or not this channel is open.

Returns:

true if, and only if, this channel is open

close

void close()
    throws IOException

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.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException - If an I/O error occurs