[RyanHamilton]

If you are looking for something lighter weight to run java snippets checkout http://jpad.io I made it to avoid writing the usual class/main boilerplate when all I wanted was to write a few lines of code to explore something.

[akerro]

JPad looks like a IDE dedicated to learning new things in a programming language. Eg. you want to try java9 feature without creating new project, writing new class. Gonna try it today. Thanks.

[LaSombra]

That's quite interesting. I usually use GroovyConsole.