Redundant step in 'Stream' or 'Optional' call chain

Reports redundant Stream or Optional calls like map(x -> x), filter(x -> true) or redundant sorted() or distinct() calls.

Note that a mapping operation in code like streamOfIntegers.map(Integer::valueOf) works as requireNonNull() check: if the stream contains null, it throws a NullPointerException, thus it's not absolutely redundant. Disable the Report redundant boxing in Stream.map() option if you do not want such cases to be reported.

This inspection only reports if the language level of the project or module is 8 or higher.