Remove all white spaces and create an fixed-size or immutable List (See asList
API docs)
final String str = "dog, cat, bear, elephant, ..., giraffe";
List<String> list = Arrays.asList(str.replaceAll("\\s", "").split(","));
// result: [dog, cat, bear, elephant, ..., giraffe]
It is possible to also use replaceAll(\\s+", "")
but maximum efficiency depends on the use case. (see @GurselKoca answer to Removing whitespace from strings in Java)