Java collections convert a string to a list of characters

Question

I would like to convert the string containing abc to a list of characters and a hashset of characters. How can I do that in Java ?

List

        

Answer 1

You can do this without boxing if you use Eclipse Collections:

CharAdapter abc = Strings.asChars("abc");
CharList list = abc.toList();
CharSet set = abc.toSet();
CharBag bag = abc.toBag();

Because CharAdapter is an ImmutableCharList, calling collect on it will return an ImmutableList.

ImmutableList immutableList = abc.collect(Character::valueOf);

If you want to return a boxed List, Set or Bag of Character, the following will work:

LazyIterable lazyIterable = abc.asLazy().collect(Character::valueOf);
List list = lazyIterable.toList();
Set set = lazyIterable.toSet();
Bag set = lazyIterable.toBag();

Note: I am a committer for Eclipse Collections.