WritableByteChannel

public interface WritableByteChannel implements Channel

Known Indirect Subclasses ByteChannel, DatagramChannel, FileChannel, GatheringByteChannel, Pipe.SinkChannel, SeekableByteChannel, SocketChannel ByteChannel A channel that can read and write bytes.  DatagramChannel A selectable channel for datagram-oriented sockets.  FileChannel A channel for reading, writing, mapping, and manipulating a file.  GatheringByteChannel A channel that can write bytes from a sequence of buffers.  Pipe.SinkChannel A channel representing the writable end of a Pipe.  SeekableByteChannel A byte channel that maintains a current position and allows the position to be changed.  SocketChannel A selectable channel for stream-oriented connecting sockets.

A channel that can write bytes.

Only one write operation upon a writable channel may be in progress at any given time. If one thread initiates a write operation upon a channel then any other thread that attempts to initiate another write operation will block until the first operation is complete. Whether or not other kinds of I/O operations may proceed concurrently with a write operation depends upon the type of the channel.

Public Method Summary

abstract int

write(ByteBuffer src) Writes a sequence of bytes to this channel from the given buffer.

Inherited Method Summary

From interface java.nio.channels.Channel

abstract void	close() Closes this channel.
abstract boolean	isOpen() Tells whether or not this channel is open.

From interface java.io.Closeable

abstract void

close() Closes this stream and releases any system resources associated with it.

From interface java.lang.AutoCloseable

abstract void

close() Closes this resource, relinquishing any underlying resources.

Public Methods

public abstract int write (ByteBuffer src)

Writes a sequence of bytes to this channel from the given buffer.

An attempt is made to write up to r bytes to the channel, where r is the number of bytes remaining in the buffer, that is, src.remaining(), at the moment this method is invoked.

Suppose that a byte sequence of length n is written, where 0 <= n <= r. This byte sequence will be transferred from the buffer starting at index p, where p is the buffer's position at the moment this method is invoked; the index of the last byte written will be p + n - 1. Upon return the buffer's position will be equal to p + n; its limit will not have changed.

Unless otherwise specified, a write operation will return only after writing all of the r requested bytes. Some types of channels, depending upon their state, may write only some of the bytes or possibly none at all. A socket channel in non-blocking mode, for example, cannot write any more bytes than are free in the socket's output buffer.

This method may be invoked at any time. If another thread has already initiated a write operation upon this channel, however, then an invocation of this method will block until the first operation is complete.

Parameters

src	The buffer from which bytes are to be retrieved

Returns

• The number of bytes written, possibly zero

Throws

NonWritableChannelException	If this channel was not opened for writing
ClosedChannelException	If this channel is closed
AsynchronousCloseException	If another thread closes this channel while the write operation is in progress
ClosedByInterruptException	If another thread interrupts the current thread while the write operation is in progress, thereby closing the channel and setting the current thread's interrupt status
IOException	If some other I/O error occurs