Emacs: My awesome Java environment

A talk by torstein @ skybert dot net

Hi, I'm Torstein

• Been in ❤ with Emacs since 2000

I've used many Java plugins/packages

• java-mode (2000 → 2001)
• JDE/JDEE (2001 → 2009)
• gtags
• jtags
• Malabar (2011 → 2012)
• JDIbug (2009 → 2011)
• eclim (2013 → 2017)
• Meghanada (2017 → 2018)
• lsp-java (2018 → present)

My requirements

• Zero conf: Easily setup a new Java project
• Fast: must handle large projects
• Large meaning ~7000 classes (Tomcat has 2200)
• Easy to switch between projects

Seeing is believing

Will use a wee app,
cheese-shop to show the
Java features in Emacs.

Seeing is believing

• Auto completion
• Code navigation
• Jump to source of 3rd party libraries
• Import classes
• Static import methods and fields
• Run JUnit tests from within Emacs

Seeing is believing

• Linting
• Unused variables
• Wrong syntax
• Missing generics

Seeing is believing

• Implement missing class
• Implement missing method

Seeing is believing

• Debug application from within Emacs
• Debugger with conditional break points

Seeing is believing

• Refactoring: rename variable
• Refactoring: extract to variable
• Refactoring: extract to method

System.exit(0);

✏ torstein @ skybert dot net