Your examples are correct.

More and more, I see Americans following the British on this, and leaving the periods out of these initial nicknames.

"Where are you going, JJ?"

How about:
"Come here, JJ," Mary said.

 

Your examples are correct.

More and more, I see Americans following the British on this, and leaving the periods out of these initial nicknames.

"Where are you going, JJ?"

How about:
"Come here, JJ," Mary said.

I know J.J. is preferred to JJ in every grammar book I've read but I just haven't read how to use punctuation after it.

The "correct" way looks weird to me though and it actually makes me not want to use initials for a name.

 

I know J.J. is preferred to JJ in every grammar book I've read but I just haven't read how to use punctuation after it.

The "correct" way looks weird to me though and it actually makes me not want to use initials for a name.

Why not have his "official" name be J.J., but his nickname Jayjay?

OTH, the punctuations seems a little bit strange at first, but I think it's perfectly correct.

* Where is J.J.?
but
* Ha, there is J.J. (no extra period)

 

Late night punctuation question: if I have a character who uses initials for their first name (J.J. for example) how do you use punctuation with that?

For instance is the placement of the question mark correct in the following?
"Where are you going, J.J.?"

How about:
"Come here, J.J.," Mary said.

In other words is J.J. functionally the same as a full name like Bob?

You're correct, Joseph. Exception would be:

"Go away, J.J." Mary slammed the door.

IOW the period in the name does double-duty in a sentence.

 

Why not have his "official" name be J.J., but his nickname Jayjay?

You can call me Doubleyouecks.

 

The name I was thinking of when I started this thread is a major character in my new story named Andrea Juno, but goes by "A.J."
Knowing the problem I would have using the nickname correctly (I just hate seeing A.J.? written for some reason) I considered calling her "Ajay" but ended up just referring to her as "Juno" in the published version. She's a tough-as-nails first officer and so the use of her last name fits I think. She still has the same nickname, but only a few friends are allowed to call her that, and when they do, I used "AJ" with no periods. If that is the more common way to do it in England, than so be it. This is the distant future, after all, and maybe British spelling will prevail after all.

 

If you want to keep the full stops (periods) I would write it as:

"Where are you going J.J?" as the question mark replaces the full stop. It might not be grammatically correct, but I think it looks more pleasing.

 

I have a character who goes by AJ, with no periods between the letters, because I just can't stand looking at the final period followed by a comma or sentence-ending punctuation. I keep it consistent all the way through, so I doubt anyone will find my intentions unclear.

 

If you want to keep the full stops (periods) I would writer it as:

"Where are you going J.J?" as the question mark replaces the full stop. It might not be grammatically correct, but I think it looks more pleasing.

As a reader that would drive me nuts, it looks like the author forgot the period in J.J..

 

As a reader that would drive me nuts, it looks like the author forgot the period in J.J..

And you would be correct.

However when the sentence ends on a period, the rule is not to put a second one. The last period of initials serves a double purpose.
http://www.quickanddirtytips.com/education/grammar/ending-sentence-abbreviation

"It looks like the author forgot the period in J.J."