Some of my Java solutions for CodeWars challenges.
If you are not familiar with CodeWars these are usually small solutions to specific challenges that must be fitted in one file, so I'd refactorize some of these if they were intended to be used in a real world problem by splitting the code along several classes and files.
Find these and more in my CodeWars' profile here: https://www.codewars.com/users/fmmarzoa