AsynchronousSocketChannel write()

[Alan Bateman]

Avinash Lakshman wrote:
> Hi All
>
> I want to use the write() on the AsynchronousSocketChannel which has 
> no timeout semantics. I also want to pool these connections that I 
> use. Now if I have multiple threads writing into the same connection, 
> even though the writes are synchronized, I get a WritePendingException 
> because a previous write has not completed. What is the general 
> paradigm for handling this? Do I need to keep track of pending writes etc?
I wonder if this is the right API for what you are doing. If you've got 
multiple threads wanting to write to the same stream then the writing 
will need to be coordinated to avoid "corrupting" the stream. A write to 
a channel is not guaranteed to write all the remaining bytes in the 
buffer and so the buffer prepared by one of the threads may actually 
require several I/O operations. The only thing I can suggest is that you 
maintain a queue of buffers to be written, and use the the completion 
notification to initiate the next write operation (which might be from 
the same buffer, or the next buffer in the queue). I think there are 
other folks on this mailing list that have been through this before and 
they might be able to advise or provide samples from their own usage.

-Alan.