AVL Tree implementation in Java
https://en.wikipedia.org/wiki/AVL_tree
All operations, worst cases always O(logn).

Not thread safe.
As described here:
https://stackoverflow.com/questions/16257761/difference-between-red-black-trees-and-avl-trees
Lookup is faster for large trees, here more than 15000000 elements.

Still few debug functions - under development - but core functions tested and working.

More, stuff, also here: https://lion137.blogspot.com/