IntelliJ IDEA

IntelliJ IDEA is another highly popular Java debugging tool that allows developers to easily debug simple code as well as multi-threaded Java applications.
It does all the basic work which debuggers are meant for such as, set breakpoints, step through your code, evaluate expressions, inspect variables, and a range of other debugging processes.

Apart from the basic operations, IntelliJ IDEA also allows easier detection of unexpected flows and states, deadlocks, livelocks, and more.