Libraries
jvisualvm
Visualize memory footprint of java app
Already bundled with jdk
Picocli
Picocli aims to be the easiest way to create rich command line applications that can run on and off the JVM.
Relience4j
https://github.com/resilience4j/resilience4j
vert.x
Vert.x is a tool-kit for building reactive applications on the JVM
Vert.x core contains fairly low-level functionality, including support for HTTP, TCP, file system access, and various other features. You can use this directly in your own applications, and it's used by many of the other components of Vert.x.
Eclipse Vert.x isevent drivenandnon blocking. This means your app can handle a lot of concurrency using a small number of kernel threads. Vert.x lets your app scale with minimal hardware.