• مهما طال الليل@lemm.ee
    link
    fedilink
    arrow-up
    1
    arrow-down
    2
    ·
    edit-2
    7 days ago

    Main method is not public static

    It must be somewhere under the hood. Otherwise, it wont be callable and it would require an instance of an object to call. Unless the object here is the Java environment?

    No String[] args

    They are just optional I’m sure, like C and C++. You still need them to read command line arguments.

    All in all, these syntax improvements are welcome. I already moved on to Kotlin for Android development though.

    • JackbyDev@programming.dev
      link
      fedilink
      English
      arrow-up
      2
      ·
      edit-2
      7 days ago

      Main method is not public static

      It must be somewhere under the hood. Otherwise, it wont be callable and it would require an instance of an object to call. Unless the object here is the Java environment?

      No. From JEP-445:

      If an unnamed class has an instance main method rather than a static main method then launching it is equivalent to the following, which employs the existing anonymous class declaration construct:

      new Object() {
          // the unnamed class's body
      }.main();
      

      No String[] args

      They are just optional I’m sure, like C and C++. You still need them to read command line arguments.

      Without the preview feature enabled, it is not an optional part of the method signature. It specifically looks for a main(String[]) signature.

      • مهما طال الليل@lemm.ee
        link
        fedilink
        arrow-up
        2
        arrow-down
        6
        ·
        7 days ago

        I am not in the mood to read a technical document, but I don’t think the resulting binary/byte code should be different between the two “hello world” programs. But then again, why not?

        Without the preview feature enabled, it is not an optional part of the method signature. It specifically looks for a main(String[]) signature.

        Ah ha! So that’s what’s going on here. They almost got it right. They had the potential to make a lot of the boilerplate optional or implicit under relevant circumstances, but instead the language has two explicit switchable modes.

        Can I write a Java application in “preview feature”?

        • JackbyDev@programming.dev
          link
          fedilink
          English
          arrow-up
          7
          ·
          edit-2
          7 days ago

          I mentioned this uses preview features twice in the first comment regarding this, so I don’t know why you’re "ah ha"ing. Also you don’t need to read the technical document, I’ve quoted the entirety of the relevant text. I provided it as a citation.

          You seem confused about preview features. It’s not a switchable mode to reduce boiler plate. I find the name very clear, but here is more information. From JEP-12

          A preview feature is a new feature of the Java language, Java Virtual Machine, or Java SE API that is fully specified, fully implemented, and yet impermanent. It is available in a JDK feature release to provoke developer feedback based on real world use; this may lead to it becoming permanent in a future Java SE Platform.

          As an example, JDK 17 added pattern matching for switch statements as a preview, and by JDK 21 it was added as a full fledged feature that doesn’t require usage of the enable preview flag. Presumably in some future release of Java this feature will not require the usage of a flag.

          • مهما طال الليل@lemm.ee
            link
            fedilink
            arrow-up
            1
            arrow-down
            2
            ·
            edit-2
            6 days ago

            It is pretty late for me. Sorry. And thank you for your patience. Repeating it three times helped.

            It will be interesting to find out if the resulting binary is the same or not and what’s possible once it matured.

            • JackbyDev@programming.dev
              link
              fedilink
              English
              arrow-up
              3
              ·
              7 days ago

              Yes, because it’s genuinely not a static method. It’s an instance method. Also the signature is different. It’s not some sort of mere syntactic trick that translates void main() to public static void main(String[] args).