• lurklurk@lemmy.world
    302·
    10 months ago

    Hello World

    30 minutes of boilerplate

    writing imports

    $ cat < Hello.java
public class Hello {
  public static void main(String args[]) {
    System.out.println("Hello world!");
  }
}
EOF
$ java Hello.java
Hello world!

    ok

      • Classy@sh.itjust.works
        9·
        10 months ago

        Oh my god I got fucked by a python script once because of a single space. It took forever to figure out what went wrong

        • TonyOstrich@lemmy.world
          3·
          10 months ago

          I refuse to code in Python without a really good IDE and linting like PyCharm. When using PyCharm it’s very rare I have issues like this, because it catches them in one way or another, but I notice it catches those kinds of issues a lot when I’m coding soooooooo…

          I have also setup the IDE to specifically color code comments like

          ’ # End If and ’ # Next

          in the same style as their beginning statements as I find it much easier to visually scam through code when they are present.

        • greenkarmic@lemmy.ca
          2·
          10 months ago

          You can’t use Python without a linter. I have everything setup in vscode to use tabs yet copilot autocomplete insists on inserting random spaces everywhere creating indentation errors. The linter is essential to quickly see and fix them.

      • JackbyDev@programming.devEnglish
        3·
        10 months ago

        **kwargs

        “No, I don’t use type annotations because they don’t actually do anything. In fact I purposefully give this parameter different types for different behaviors. How is that confusing?”

      • lurklurk@lemmy.world
        3·
        10 months ago

        Python has its drawbacks but it also has a pretty useful standard library so as a language for small scripts, one can do much worse

    • JackbyDev@programming.devEnglish
      7·
      10 months ago

      This is getting a little better nowadays.

      > cat Hello.java
void main() {
    System.out.println("Hello, World!");
}
> java --enable-preview Hello.java
Hello, World!

      Things to notice:

      1. No compilation step.
      2. No class declaration.
      3. Main method is not public static
      4. No String[] args.

      This still uses preview features though. However, like you demonstrated already, compilation is no longer a required step for simplistic programs like this.

      • cashew@lemmy.world
        41·
        10 months ago

        Microsoft Java is a one-liner these days.

        > cat program.cs
Console.WriteLine("Hello, World!");
> dotnet run
Hello, World!
      • Valmond@lemmy.world
        2·
        10 months ago

        System.base.stuff.output.out.printfunctions.println

        Or so it felt every time you wanted to dump something into the console…

        • JackbyDev@programming.devEnglish
          2·
          10 months 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.

            • JackbyDev@programming.devEnglish
              7·
              10 months 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.

                • JackbyDev@programming.devEnglish
                  3·
                  10 months 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).

    • meowMix2525@lemm.ee
      3·
      10 months ago

      I got the impression they skipped the hello world cause it was too easy and they wanted to get right to writing their app, so they moved on to more advanced stuff without having a real grasp of the basics