Client disconnection notification for NIO server

Question

A server accepts connections from clients and registers accepted channels for reading:
while (true)
    if (selector.select()>0)
        Iterator<SelectionKey> iterator = selector.selectedKeys().iterator();
        while(iterator.hasNext())
            SelectionKey opKey = iterator.next();
            iterator.remove();
            if (opKey.isAcceptable())
                clientSocketChannel = serverSocketChannel.accept();
                clientSocketChannel.configureBlocking(false);
                clientSocketChannel.register(selector, SelectionKey.OP_READ);
. . .One of the server's clients disconnects from it by means of socketChannel.close() while the servert is locked with selector.select() (that is the server have nothing to read from its clients and nobody is connecting to it).Will the server be unlocked when the client performs socketChannel.close()? If so, what notification/exception will the server receive?

Answer 1

One of the server's clients disconnects from it by means of socketChannel.close() while the servert is locked with selector.select()The select() will immediately return; the corresponding channel will be readable; and the read() will return -1.