docs: public void init() {
        registerListener();
        for (int i = 0; i < entries.length; ++i) {
           final int index = i;
           awaitCounterOperation(readOnlyMap.eval(entries[index].key, ReadFunction.getInstance())
                 .thenAccept(value -> initEntry(index, value)));
        }
        selector.updatePreferredKeys();
     }