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kotlinlang

I'm trying to run a _.class_ file compiled through Gradle, *just for the sake of it* but I haven't had any success. I want to use `java`, how can I make it run? I've tried stuff like this:
```$ java -cp "/usr/share/kotlin/lib/kotlin-stdlib.jar:." kott.AppKt     
Error: Could not find or load main class kott.AppKt
Caused by: java.lang.ClassNotFoundException: kott.AppKt

$ java AppKt 
Error: Could not find or load main class AppKt
Caused by: java.lang.NoClassDefFoundError: kott/AppKt (wrong name: AppKt)```

classpath `.` implies `kott.AppKt` is can be found at `./kott/AppKt.class`. is it?

Are you sure you have kott directory where you are starting and AppKt class (or App file)

```/home/manuel/dev/kott/app/build/classes/kotlin/main/kott&gt; ls
App.class  AppKt.class```

Java only works with the correct directory structure

`/home/manuel/dev/kott/app/build/classes/kotlin/main` here

Java is expecting to load `kott.AppKt` from the file `./kott/AppKt.class`. if it is actually at `./AppKt.class` it will not be found.

```/home/manuel/dev/kott/app/build/classes/kotlin/main&gt; java AppKt
Error: Could not find or load main class AppKt
Caused by: java.lang.ClassNotFoundException: AppKt```
I dunno what I'm doing wrong yet

```/home/manuel/dev/kott/app/build/classes/kotlin/main&gt; java <http://kott.App|kott.App>
Error: Main method not found in class <http://kott.App|kott.App>, please define the main method as:
   public static void main(String[] args)
or a JavaFX application class must extend javafx.application.Application```
okay it works now (except it doesn't, but I know why this doesn't work) thanks for the help

if you use Gradle's `application` plugin, it can generate a startup script that encapsulates all the JAVA_HOME and classpath manipulation

Kotlin usually generate `{FileName}Kt` file encapsulating the top-level main function.

You can rename it through `@file:JvmName("...")`

not just main but any top-level declarations (e.g. outside of a class or interface). because Java requires everything belong to a class

and yes, although of course `@file:` annotations have to precede all other content in the file (except whitespace and comments, those are allowed)

Oh yeah I actually landed on <https://stackoverflow.com/a/34513057/13335378|here> minutes before I made this thread, and I checked the docs too

I kept doing stupid mistakes because I'm not used to the compiler at all

Just use the kotlin jupyter kernel if you like to build and test only a few code, it'll be alot more productive. Or else use the gradle to build your project.