Get values from MultiValueMap

Question

I use this code to get values from an HTTP request:

@PostMapping(consumes = MediaType.APPLICATION_FORM_URLENCODED_VALUE, value = "/v1/notification")
  public ResponseEntity<String> handleNotifications(@RequestBody MultiValueMap<String, Object> keyValuePairs) {

    LOGGER.debug("handleFormMessage");
    LOGGER.debug("keyValuePairs: {}", keyValuePairs);

    String unique_id = String.valueOf(keyValuePairs.get("unique_id"));

    System.out.println("!!!!!!!!!!!!!! ! unique_id " + unique_id);
}

But I get this value: !!!!!!!!!!!!!! ! unique_id [24q376c3ts2kh3o3220rry322dfe2k7y].

Is there a way to remove [] from the String without the classical String result = str.substring(0, index) + str.substring(index+1);?

Is there a way to get the values?

I use this to post the values:

Answer 1

If you always provide only one value for unique_id, you can, instead of get, use getFirst which

Returns the first value for the given key

Your code would go like this:

String unique_id = String.valueOf(keyValuePairs.getFirst("unique_id"));

Remember, this method actually returns the first value for the specified key, or null if none is found.

---

In case you send more than one value you need to treat them as a Collection. For example:

Collection<String> unique_ids = keyValuePairs.get("unique_id");

After that you can do with all the ids as you wish, for example, print them:

unique_ids.stream().forEach(System.out:println);

Answer 2

MultivaluedMap is an interface inheriting Map, and how you can see the object you get is a list

public interface MultivaluedMap<K,V> extends Map<K,List<V>>

Then you can do this and get the first element of the list:

String unique_id = String.valueOf(keyValuePairs.getFirst("unique_id"));