Create List of enum from comma separated String in Java

Question

I need to create a List of enum from a comma separated String. I have some configurations in properties file which are mainly a list of HttpStatus

like:

some.config=TOO_MANY_REQUESTS,GATEWAY_TIMEOUT,BAD_GATEWAY

This configurations can be bind to a LIST as:

@Value("#{'${some.config}'.split(',')}")
private List<HttpStatus> statuses;

Now can this be done with a single line of my code. I am receiving the String as following:

 @Bean(name = "somebean")
 public void do(@Value("${some.config:}") String statuses) throws IOException {

        private List<HttpStatus>  sList = StringUtils.isEmpty(statuses) ? 
        globalSeries : **Arrays.asList(statuses.split("\\s*,\\s*"));**

 }

Arrays.asList(series.split("\s*,\s*")); will create a List of string, now can I create a List of enum instead, otherwise I need to iterate the temp List then create a List of enum.

How about something like `List list = Stream.of(yourData.split(delimiter).map(YourEnum::valueOf).collect(Collectors.toList())`? Anyway possibly related: [Lookup Java enum by string value](https://stackoverflow.com/q/604424) — Pshemo, Jun 08 '18 at 09:23
@Pshemo I though the same, just somehow handle invalid input by catching `IllegalArgumentException` somewhere — Glains, Jun 08 '18 at 09:25
Are you sure you want a `List` (allow duplicates, maintain an order)? For most practical use cases, you want a `Set`, likely an `EnumSet`. `Arrays.stream(statuses.split(",")) .map(s -> HttpStatus.valueOf(s.trim())) .collect(Collectors.toCollection( () -> EnumSet.noneOf(HttpStatus.class) ))` — Holger, Jun 08 '18 at 10:03

score 8 · Accepted Answer · answered Jun 08 '18 at 09:25

8

You could just use a stream and map all the String values into the Enum values using Enum#valueOf

Arrays.stream(statuses.split("\\s*,\\s*"))
      .map(HttpStatus::valueOf)
      .collect(Collectors.toList());

answered Jun 08 '18 at 09:25

Yassin Hajaj

21,337
9
51
89

score 5 · Answer 2 · answered Jun 08 '18 at 09:30

5

You can also use a Pattern to accomplish the task at hand:

Pattern.compile(regex)
       .splitAsStream(myString)
       .map(HttpStatus::valueOf)
       .collect(toList());

answered Jun 08 '18 at 09:30

Ousmane D.

54,915
8
91
126

Create List of enum from comma separated String in Java

2 Answers2