Is main a valid Java identifier?

Gary Bak :

One of my kids is taking Java in high school and had this on one of his tests:

Which of the following is a valid identifier in Java?

a. 123java
b. main
c. java1234
d. {abce
e. )whoot

He answered b and got it wrong.

I looked at the question and argued that main is a valid identifier and that it should have been right.

We took a look at the Java spec for identifiers and it reinforced that point. We also wrote a sample program that had a variable called main, as well as a method. He created a written rebuttal that included the Java documentation reference, the test program and the teacher ignored it and says the answer is still incorrect.

Is main a valid identifier?

rgettman :

public class J {
    public static void main(String[] args)
    {
        String main = "The character sequence \"main\" is an identifier, not a keyword or reserved word.";
        System.out.println(main);
    }
}

This compiles, and when executed, emits this output:

The character sequence "main" is an identifier, not a keyword or reserved word.

The character sequence main is an identifier, not a keyword or reserved word.

The relevant section of the JLS is 3.8:

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

Identifier:

    IdentifierChars but not a Keyword or BooleanLiteral or NullLiteral

IdentifierChars:

    JavaLetter {JavaLetterOrDigit}

JavaLetter:

    any Unicode character that is a "Java letter"

JavaLetterOrDigit:

    any Unicode character that is a "Java letter-or-digit"

The character sequence main fits the above description and is not in the keyword list in Section 3.9.

(The character sequence java1234 is also an identifier, for the same reasons.)

Is main a valid Java identifier?

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