Method getListOfStrings

core/src/main/java/io/grpc/internal/JsonUtil.java:70–77

Gets a list from an object for the given key, and verifies all entries are strings. If the key is not present, this returns null. If the value is not a List or an entry is not a string, throws an exception.

(Map<String, ?> obj, String key)

   * throws an exception.
   */
  @Nullable
  public static List<String> getListOfStrings(Map<String, ?> obj, String key) {
    List<?> list = getList(obj, key);
    if (list == null) {
      return null;
    }
    return checkStringList(list);
  }

  /**
   * Gets an object from an object for the given key.  If the key is not present, this returns null.