Are you a developer who is tired of null pointer exceptions, SQL
injections, concurrency errors, and other errors that appear during
testing or in the field? You need a tool that can guarantee the
absence of these errors, and of many other important bugs.

Are you a software architect who wants to implement custom checks that
enforce correct usage and prevent errors? You need a framework that
supports you in creating a code checker that works at the semantic
level.

This tutorial is aimed at both audiences. It will teach you about
pluggable type-checking and the Checker Framework, an open-source tool
that provides more than a dozen checkers that are ready to use,
including ones for nullness, formatting, and concurrency. They have
found hundreds of bugs in well-tested open source code, including from
Oracle, Google, Apache, etc., and even when other tools like FindBugs
gave the code a clean bill of health. The Checker Framework also
enables you to create your own new pluggable type system.

You will leave the tutorial ready to improve your code.
The tool is freely available at http://CheckerFramework.org/.
You have nothing to lose but your bugs!