In a few places in java.time code performs ConcurrentHashMap.putIfAbsent and then ConcurrentHashMap.get by the same key.
For example java.time.format.DateTimeTextProvider#findStore:

    private Object findStore(TemporalField field, Locale locale) {
        Entry<TemporalField, Locale> key = createEntry(field, locale);
        Object store = CACHE.get(key);
        if (store == null) {
            store = createStore(field, locale);
            CACHE.putIfAbsent(key, store);
            store = CACHE.get(key);
        }
        return store;
    }

Instead of separate dive into ConcurrentHashMap internal, we can just reuse result of putIfAbsent call.

            Object prev = CACHE.putIfAbsent(key, store);
            if (prev != null) {
                store = prev;
            }