Register multiple SelectionKey

Question

I am working with Java selectors in NIO. I am registering my selection key/ interest key with the particular channels and selectors. Now, my requirement is to have two or more interest sets for a particular selector.

What I did is make two selectionkeys with different selection options as follows:

    try {
        Selector selector = Selector.open();
        ServerSocketChannel channel = ServerSocketChannel.open();
        //FileChannel channel = new FileInputStream("").getChannel();

        channel.configureBlocking(false);

        SelectionKey key1 = channel.register(selector, SelectionKey.OP_READ);
        SelectionKey key2 = channel.register(selector, SelectionKey.OP_WRITE);

    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

My question is, is there any way i can avoid making two diffrent keys?

Answer 1

You can binary-or the keys together to create a single interest:

SelectionKey key = channel.register(selector, SelectionKey.OP_READ | SelectionKey.OP_WRITE);