generate class is MainKt

# getting-started

[claudiug]

generate class is MainKt

[karelpeeters]

And what goes wrong with this?

[claudiug]

I have this

[claudiug]

java -jar build/libs/files-1.0-SNAPSHOT.jar
Error: Could not find or load main class MainKt
Caused by: java.lang.ClassNotFoundException: MainKt

[claudiug]

even if in build/classes/ I have: kotlin/main/MainTk.class

[karelpeeters]

Ah, kotlin and main shouldn't actually be part of the package.

[karelpeeters]

Take a look in the generated jar, MainKt.class is probably top level.

[claudiug]

hmm

[claudiug]

it looks like this

[claudiug]

// IntelliJ API Decompiler stub source generated from a class file
// Implementation of methods is not available

public fun main(args: kotlin.Array<kotlin.String>): kotlin.Unit { /* compiled code */ }

[karelpeeters]

Okay but what's the path of that file within the jar?

[karelpeeters]

Probably not main/kotlin/MainKt.class

[claudiug]

Screenshot 2018-11-28 at 13.59.13.png

[claudiug]

the Main.tk is this

[claudiug]

package main.kotlin

fun main(args: Array<String>) {
    println("Hello World")
}

[claudiug]

jar {
    manifest {
        attributes 'Main-Class': 'main.kotlin.MainKt'
    }
    // Add this
    from {
        configurations.compile.collect {
            it.isDirectory() ? it : zipTree(it)
        }
    }
}

[karelpeeters]

You actually wrote package main.kotlin is the source file? src/main/kotlin is supposed to be the root package simple smile

[claudiug]

intellij told me that 😄

[claudiug]

lol

[claudiug]

let me remove that, from code and build

[claudiug]

same 😕

[claudiug]

I will be out of hair soon :((

[karelpeeters]

So to recap: there's a manifest in your jar that points to the exact right path within the jar?

[karelpeeters]

(don't look at the build folder, actually open the jar with 7zip or something)

[claudiug]

and look for?

[claudiug]

manifest?

[karelpeeters]

manifest and the path to MainKt.class

[claudiug]

moment

[claudiug]

Screenshot 2018-11-28 at 14.13.54.png

[claudiug]

this is how it look unzip

[claudiug]

manifest:

Manifest-Version: 1.0
Main-Class: main.kotlin.MainKt

[aarjav]

Looks like the sourceSets are overridden to be eclipse style with src folder as the root so main.kotlin package is correct. Also line 46 has no effect since it is overridden by line 48. Also you may want to look into using shadow jar plugin https://github.com/johnrengelman/shadow

[karelpeeters]

But the jar end result looks right :/

[claudiug]

yup

[claudiug]

I will clone this: https://github.com/niksw7/gradle-kotlin-demo

[claudiug]

and is working 😕

[claudiug]

the repo that I clone

[claudiug]

insane! 😐

[aarjav]

When you decompile main class does it have same main method signature

[aarjav]

In the one that's working

[claudiug]

https://github.com/niksw7/gradle-kotlin-demo this one works

[claudiug]

I'm baffled now 😕

[claudiug]

anyway, thanks for the time and the help. I guess I will learn and read more about gradle

[claudiug]

I'm trying to do a tiny kotlin script -> jar and then use graal to build a native image 🙂