I've been working for a bit of time with both SparkJava and some custom command-line tools, and I wanted to have a simple but efficient validation library, so I decided to make one myself.<p>I just released the v0.2.0, with a concrete documentation, API documentation (Javadoc), and automated CI for tests.<p>Here's the link: <a href="https://gitlab.com/Artemix/validator" rel="nofollow">https://gitlab.com/Artemix/validator</a><p>I'm open to any suggestion/recommendation that may help me develop this library even further.