code: private <T extends NameBearer> void addItem(T item, Map<String, T> items, String typeName) {
  		String itemName = item.getName();
  		if (items.containsKey(itemName)) {
  			throw new FuzzerException(name + ": '" + itemName + "' already present in " + typeName);
  		}
  		items.put(itemName, item);
  	}
docs: Add an item to a map.
  <p>
  @param <T>      the item type
  @param item     the item
  @param items    the item map
  @param typeName the item type name string