public abstract int write (ByteBuffer src) throws IOException

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

Exceptions:
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