apache
Add ArrayUtils.binarySearch() with a key extractor
There is Collections.binarySearch() in Java core. However, it searches for exact element which is often not usable, as the elements are typically sorted by particular field.
These methods introduce binarySearch() on arrays and (sorted) List, with ability to provide sorting key extraction function and key comparator.
The rest of semantics, behavior, parameters and return values remain consistent with Collections.binarySearch() from Java core.
Hello @kvr000,
This code should be in
ArrayUtils. TY!
@garydgregory : Yeah, got it, was busy to finish that. Fixed now, thank you.
Hello @kvr000, This code should be in
ArrayUtils. TY!@garydgregory : Yeah, got it, was busy to finish that. Fixed now, thank you.
@kvr000
Run mvn (by itself) before you push to catch build errors.
Hello @kvr000
- See my scattered comments.
- Add a method called
createSortedList(int...)that guarantees sorted results and use it.- Add tests for non-sorted input, make sure the results are predictable, we do not want a DOS for an infinite loop for example.
@garydgregory :
The createdSortedList() won't have any value. In the test, I have to see what is returned index - that's impossible with unsorted array. Additionally, now it's used also for intentionally unsorted array.
Good point for non-sorted input, I added a test. The code always does l = m+1 or h = m-1 , so it's safe.
@kvr000 Please revert the First/Last APIs.
@garydgregory : As explained in https://github.com/apache/commons-lang/pull/1270/#discussion_r1759171390 , I want to keep First/Last as I find them more useful due to their predictability. I don't think we really need original unpredictable simple binarySearch.