@Override
  public void close() {
    close(new ClosedChannelException());
  }
{@inheritDoc}
<p/>
Marks the channel as closed. No further communication will be possible. Any pending writes (that are not already
flushed) might be discarded. The process of closing the network channel is also initiated.
<p/>
The underlying network channel might not be closed immediately but no more writes will be accepted and any calls to
{@link #isOpen()} after a call to this function will return {@code false}.
ambry-rest/src/main/java/com/github/ambry/rest/NettyResponseChannel.java