protected int calculateThreshold(int newCapacity, float factor) {
        return (int) (newCapacity * factor);
    }
Calculates the new threshold of the map, where it will be resized.
This implementation uses the load factor.

@param newCapacity the new capacity
@param factor      the load factor
@return the new resize threshold
jphp-runtime/src/php/runtime/common/collections/map/AbstractHashedMap.java