Guava is a suite of core and expanded libraries that include

Compiler, Test runner, Development mode, and other tools for developing GWT applications

GWT-compatible widgets, browser abstractions, and JRE implementations for use in client applications.

JavaBeans Validation (Bean Validation) is a validation model that can add constraints to the beans with annotations ...

JavaBeans Validation (Bean Validation) is a validation model that can add constraints to the beans with annotations ...

FreeMarker is a "template engine"; a generic tool to generate text output based on templates.

Reflections - Java runtime metadata analysis

Binding/provider for SLF4J, which outputs all events to System.err. Only messages of level INFO and higher are printed.

JUnit Jupiter is the API for writing tests using JUnit 5.