This might be random.
When I debug I use the console a lot of course.
However when I debug little things here and there, which are quickly fixed, I tend to print out movie quotes instead of something else.
So I don’t know, if you cannot even image, an example would be, when debugging if an object is null, I expect it to be null, and my printout would be “I see dead people” or “It’s Alive!” - you know that kinda stuff.
Am I wierd ? :>
Well… Its better than “Check 1”, “check 2!”, “check2b!”
Nope, unless I’m weird too, well, because I do it too 
I don’t watch a lot of movies so I barely know any quotes 
haha, I usually print whatever comes to mind, often it is animal noises or obseneties haha.
It depends on my mood. But i am a big fan of caps lock
Sometimes i yell at the code (“WORK DAMMIT”)
Sometimes i am too bored to write something so i just smash my body parts against the keyboard (“UHDAKHFBJ”)
Sometimes i want to know every value i am working with ("X: " + this.x + " Y: " + this.y + " Vel: " + this.vel + Grandma.cakeRecipe + GPS.myPosition + …)
My most recent ones:
“I wantz bpi”
“I haz bpi”
“bpi iz: #”
“i can assignz bpi”
Then later in the code is a similar code block where it may have been crashing too, so I put the same text, except I replaced all the z’s with s’s in order to get some distinction.
Although I often put in “poop” “fuck your face” “thingy1” etc. I find that actually writing a single line to describe what’s happening is very helpful in the long run (just in case I end up with 25 different printouts in the process of figuring out the bug), so I’ve been trying to do that lately.
I used printouts in the above case because it was related to a server call and needed to happen at full speed - breakpoints would cause the bug to not happen.
What’s ‘bpi’?
I do the last one. All of the time. Otherwise, I use exclamations: “Here!”, “How did we get here?” (Typically my default for enum switches), “You hit your head!” (For my physics engine)
I use only (“oops”).
Exclamations in all-caps letters.
I may be boring, but i simply use a debugger and conditional breakpoints…
I wouldn’t know what I would print, because I never get bugs. 
Joking aside, I usually just write something boring like (“Attention!”)
System.out.println("This shouldn't happen");
everywhere.
That, or physics formulas.
“F = ma”
“F = c * v x B”
For most purposes the eclipse debugger is a godsend though.
Depends on how lazy I’m feeling sometimes it’s numbers so I know what went wrong where (based on the numbers printed) sometimes it’s “WHAT DID YOU DO?!?” or something like that, or I’ll just put in debug information for more info i.e. "Look what broke: " + objectThatBroke