A DESCRIPTION OF THE PROBLEM :
There are a few typos in the documentation of javax.swing.text.GapContent:
> The underlying storage is a array
Should be "an array"

> array of unicode characters
"unicode" should be written with a capital letter ("Unicode")

> Changes only require update to
Missing word / wrong grammar, either "require an update" or "require updates" (or change to "require updating ...")

> update to the the marks
Sentence has a duplicate "the"