[edwinnathaniel]

I used to do "println" debugging trick during my early days of programming until more senior people around me slap my hand and told me to use the debugger efficiently and effectively.

In Eclipse/IntelliJ you can set "Conditional Breakpoint" (only stop/break when certain conditions is met) very handy when debugging a loop. In addition to that, you can also set "breakpoint on any Exception".

Also, in Eclipse/IntelliJ, when the debugger hits the breakpoint, you could execute Java code within the context of that breakpoint (of course, java.lang is given by default in addition to the context of that breakpoint).

I've never done more complex debugging than that but I'm guessing you can write almost anything you want within the "evaluate window" in those IDEs.