允许推回的java fifo队列？

Question

is there a fifo queue implementation that provides for replacing the head element after a peek?

i'd like to use this to push a partially written buffer back onto the queue after a partial write onto a network connection (when using java nio selector).

this would be a bit cleaner than sticking the partially written buffer as an attachment on the selection key, but if there's no convenient implementation available I'll have to use that.

Answer 1

You can use a Deque which allows you to add to the start or the end.

However, if you have a partial write and your buffers are not huge, you could have a slow consumer and you might consider a different action such as closing the connection.

Answer 2

After a peek the head element is undisturbed, so your question doesn't make sense. Just peek, try the write, and if there is nothing left then remove the buffer from the queue.