Java NIO - 非阻塞连接

Question

在客户端的非阻塞连接中，可能是服务器未启动且无法建立连接的情况。我使用选择器等待OP_CONNECT确定是否可以通过以下方式建立连接：

connection = SocketChannel.open();
connection.configureBlocking(false);

// Kick off connection establishment
connection.connect(hostAddress);

connection.register(selector, SelectionKey.OP_CONNECT);
this.selector.select(2000);

// Iterate over the set of keys for which events are available
Iterator<SelectionKey> selectedKeys = this.selector.selectedKeys().iterator();
if (!selectedKeys.hasNext()) {
    throw new IllegalStateException("\"Could not connect to \" + hostAddress");
}
SelectionKey key = selectedKeys.next();
boolean valid = key.isValid();

if (!key.isConnectable()) {
    throw new IllegalStateException("\"Could not connect to \" + hostAddress");
}
finishConnection(key);

但是，即使我没有启动服务器，key.isConnectable()也会返回true ...我不明白为什么会这样，以及如何确保我只再次调用selector.select()当我连接时