code: private static String[] normalizeKeys(Object keys) {
  		if (keys instanceof Tuple) {
  			Tuple tupleKeys = (Tuple) keys;
  			if (tupleKeys.getArity() == 0) {
  				return new String[0];
  			}
  			if (tupleKeys.getField(0) instanceof Integer) {
  				String[] stringKeys = new String[tupleKeys.getArity()];
  				for (int x = 0; x < stringKeys.length; x++) {
  					stringKeys[x] = "f0.f" + (Integer) tupleKeys.getField(x);
  				}
  				return stringKeys;
  			}
  			if (tupleKeys.getField(0) instanceof String) {
  				return tupleToStringArray(tupleKeys);
  			}
  			throw new RuntimeException("Key argument contains field that is neither an int nor a String: " + tupleKeys);
  		}
  		if (keys instanceof int[]) {
  			int[] intKeys = (int[]) keys;
  			String[] stringKeys = new String[intKeys.length];
  			for (int x = 0; x < stringKeys.length; x++) {
  				stringKeys[x] = "f0.f" + intKeys[x];
  			}
docs: ====Utility=======================================================================================================