Try to avoid "flag arguments"

[leonardofl]

According to the Clean Code book this is ugly (very hard to read):

String actual = StringSplit.newSplit(3, true).split(DATA);

Maybe you could do:

String actual = StringSplit.newSplit(3).trimmed(true).split(DATA);

Off course, this can complicate your StringArraySplitterBuilder. So I'm not sure how it's feasible.

By the way, I would suggest to use trimmed=true as default. It seems most of the user will prefer this.

[ortolanph]

Using trimmed=true will be a valuable change.
I will check the feasibility to add a new method to denote trimmed strings. By the way, if it's to avoid flags, I would prefer to use:

String actual = StringSplit.newSplit(3).trimmed().split(DATA);

[leonardofl]

f it's to avoid flags, I would prefer to use...

Indeed, much better!