Create Java 8 Stream from ArrayNode

Question

Is it possible to create stream from com.fasterxml.jackson.databind.node.ArrayNode?
I tried:

ArrayNode files = (ArrayNode) json.get(\"files\")         


        

Answer 1

ArrayNode#elements returns an Iterator over it's elements you can use that to create a Stream (by leveraging StreamSupport). StreamSupport requires a Spliterator and to create a Spliterator from an Iterator you can use the Spliterators class.

  ArrayNode files = (ArrayNode) json.get("files");
  Stream  elementStream = StreamSupport.stream(Spliterators
                  .spliteratorUnknownSize(files.elements(),
                        Spliterator.ORDERED),false);

cyclops-streams has a StreamUtils class has a static method that makes this a bit cleaner (I am the author).

 ArrayNode files = (ArrayNode) json.get("files");
 Stream  elementStream = StreamUtils.stream(files.elements());

Taking into account @JB Nizet's answer that ArrayNode is an iterable with StreamUtils you can pass in the ArrayNode and get the Stream back directly.

Stream  elementStream = StreamUtils.stream((ArrayNode) json.get("files"));