Simple method to get a random element from a map based on a weight

weighted_method.java

/**
*
* @param objects: A Map containing the objects to choose from, where the keys represent the objects and the values represent their respective weights.
* @return Returns a randomly selected element from a Map, with selection probabilities proportional to each element's weight.
* @param <T> A randomly selected element from the Map, or null if the Map is empty.
*/
public static <T> T getRandomWeightedElement(Map<T, Number> objects) {
  double sum =  objects.values().stream().mapToDouble(Number::doubleValue).sum();
  for (T item : objects.keySet()) {
    random -= objects.get(item).doubleValue();
    if (random <= 0.0d) {
      return item;
    }
  }
  return null;
}