Simpliest way to convert array of Integer to array of String in Java 8

Question

I would like to convert an Integer[] but toArray() is giving me Object[]. How can I convert it to String[]?

Stream.of(ids).map(String::valueOf).toArray();

Not really a duplicate of the other question. This involves array of Integer[], which is a special case. — Dale Johnson, Jul 19 '16 at 01:39

score 9 · Accepted Answer · answered Jul 04 '16 at 21:44

9

String[] array = Stream.of(ids).map(String::valueOf).toArray(String[]::new);

answered Jul 04 '16 at 21:44

Reimeus

I am surprise, Is this a method reference? New keyword can be treat as method? – richersoon Jul 04 '16 at 21:47
1

@richersoon It's a reference to the constructor – Dioxin Jul 04 '16 at 21:49
1

method references can be used for constructors as well as methods – Reimeus Jul 04 '16 at 21:49
When you have an existing array, it’s recommended to use `Arrays.stream` instead. This will consistently work for `int[]`, `long[]` and `double[]` as well (you only have to use `mapToObj` instead of `map` then), whereas `Stream.of` only works for boxed values and it’s intended use case is the varargs invocation like `Stream.of(a, b, c)`… – Holger Jul 05 '16 at 16:45

Michael · Answer 2 · 2016-07-04T21:55:24.943

-1

String[] a= Arrays.toString(array).split("[\\[\\]]")[1].split(", ");

I think this should work

edited Jul 04 '16 at 21:55

answered Jul 04 '16 at 21:44

Michael

2 Answers2