Why # can not use in java identifier?

Question

Please let me explain that # can not use in java identifier. For example. int e#;

And also, let me know that # is used in java and where to use?

Is there any point to this question? Why are you concerned about `#` specifically? — Martin Smith, Feb 07 '13 at 15:02
every programming language has its syntax. Simply it works this way. As well as you can't have variable like `int 1d;` try to live with that :) — CsBalazsHungary, Feb 07 '13 at 15:05
I'm not sure about a usage in Java, but in [javadoc](http://www.oracle.com/technetwork/java/javase/documentation/index-137868.html#multiple@see) the # is used to separate Classes and the member Field/methods. — Charlie, Feb 07 '13 at 15:11
I'd advice against using this except for purposes of amusement. But you can use *all* unicode "letters" in a Java identifier, including ones that merely look like a hash-sign. So this is valid: `int c井 = 5;` — Erwin Bolwidt, Oct 23 '15 at 04:39

Darren · Answer 1 · 2013-02-07T15:06:35.053

4

Because it's not a valid symbol in the language. Just as you can't do:

int HELLO+*/\Variable;

See 3.8. Identifiers in the Java specification:

An identifier is an unlimited-length sequence of Java letters and Java digits, the first of which must be a Java letter.

edited Feb 07 '13 at 15:06

answered Feb 07 '13 at 15:00

Darren

score 3 · Answer 2 · answered Feb 07 '13 at 15:05

3

I think you need to read this:

Ask Oracle afterwards, if you still don't know!

answered Feb 07 '13 at 15:05

Bob Flannigon

2 Answers2