code: public static boolean areBooleanEquals(Boolean boolean1, Boolean boolean2) {
  		if (boolean1 != null && !boolean1.equals(boolean2)) {
  			return false;
  		} else if (boolean2 != null && !boolean2.equals(boolean1)) {
  			return false;
  		}
  		return true;
  	}
docs: Checks if two Booleans are equals.
  The booleans can be both null, one of them null or none of them null.
  
  @param boolean1 from tree tree element
  @param boolean2 from rule element
  @return true if and only if the two booleans are equal (both equal or both null)