Question

I have set like:

Set<String>

I need on each element of Set make split by ; and create new Set that will contain only 2-nd element. Should I make it directly one by one or exists better way?
Thanks.

Answer 1

If you can relax your constraint of an output being a Set<String> to being a Collection<String> you could use Guava and defer the transformation of elements until enumeration of elements through the Collections2#transform() method. You would just have to write a custom function to perform the split on an individual element.

But if you cannot/should not relax this constraint, you are best left to doing the already proposed individual iterations (as it’d be much more legible).

Code would look something like:

Set<String> input; //Given
Collection<String> output = Collections2.transform(input, new Function<String,String>() {
    @Override
    public String apply (String element) {
        // As JohnnyO says, add appropriate edge case checking...
        return element.split(";")[1]; 
    }
});