@Nullable
        protected T execute(@Nullable Reference<K, V> ref, @Nullable Entry<K, V> entry, @Nullable Entries<V> entries) {
            return execute(ref, entry);
        }
Execute the task.

@param ref     the found reference (or {@code null})
@param entry   the found entry (or {@code null})
@param entries access to the underlying entries
@return the result of the task
see #execute(Reference, Entry)
analyzer/src/main/java/nl/basjes/parse/useragent/utils/springframework/util/ConcurrentReferenceHashMap.java