Is main a valid Java identifier?

Understanding the basics: what's in a name?

The term main is a perfectly legal identifier in Java, meaning it complies with the rules set out under section 3.8 of the Java Language Specification (JLS). The only conditions: it has to start with a letter and it can be of unlimited length.

Not confined to classic use, main can undertake multiple roles:

public class main {   // So mainstream it became a class name. 
    int main;   // No more main stream than this.
    
    public void main() {   // Who needs a side hustle when you've got this?
        // This ain't your entry point, but hey, it's got style!
    }
}
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Remember though, the Java Virtual Machine(JVM) specifically looks for the public static void main(String[] args) signature and no other, to start the application. So, other uses of main won't boot up your app - your Cinderella slipper fits one foot only!

Busting Myths: A terrain less travelled

Time to debunk some myths! A method named main other than the entry point won't lead to compile-time errors. Your code won't self-destruct, and the compiler won't throw a hissy fit. Legal in the eyes of the Java documentation, main can be freely enlisted as an identifier.

Seeing is believing, right? Behold:

public class Demo {
    public void main() {
        // A valid method — not the entry point but hey, it's aspiring!
    }
    
    public static void main(String[] args) {
        // Regular day job of 'main' — being the entry point.
    }
}
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Unraveling the versatility of main can lead you to a broader understanding of Java.

Coding etiquette: Class, Method, and Variable Names

Just because main is a legal identifier doesn't mean it shouldn't be used judiciously. Leverage it without contributing to ambiguity:

• Decline variables or classes named main to avoid confusion.
• Assign the method name main only to the entry point of your application to maintain readability in your code.
• Stick to Java naming conventions to help others distinguish between classes, methods and the special main method.

Exhibit A of when not to use 'main':

public class Calculator {
    public void main() {
        // The intention is noble, but the name, not so much!
    }
}
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Here, using main as the method name could lead to a maze of misconceptions. Opt for a name that clearly represents the functionality instead, like calculate or sum.