Hello I m getting a very strange error when trying to call a kotlinlang #announcements

Hello, I'm getting a very strange error when trying to call a function. In a certain function I've written, I've wrapped my Kotlin Strings in Java Strings to benefit from the significant speedup in

java.lang.String#repeat(int)

compared to

kotlin.text.repeat(CharSequence, int)

. When I run the code in IJ, it works fine, when I call the function from Java for testing purposes, it works fine, but when I compile the jar and run it via

java -jar

, it throws a

NoSuchMethodError

, saying that there is no method

java.lang.String#repeat(int)

. Does anyone know the cause?

The function I'm calling uses Java strings so:

Copy code

kt
```fun cls(size: Int) = print(java.lang.String(
	java.lang.String(" ").repeat(size * 2 + 3) + "[1F"
).repeat(size + 2))

Ooops, looks like Slack doesn't support syntax highlighting for code blocks

ephemient

05/11/2021, 12:50 AM

https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/String.html#repeat(int)

Since: 11

if you are running with an older Java you can't use String.repeat

also, Kotlin strings are Java strings, you don't need to wrap

SirNapkin1334

05/11/2021, 12:52 AM

ah, oops, i had forgotten to set my system java back version to 15!

ephemient

05/11/2021, 12:53 AM

Copy code

(" " as java.lang.String).repeat(10)

SirNapkin1334

05/11/2021, 12:54 AM

ah, thanks, i probably should have tried that.

ephemient

05/11/2021, 12:55 AM

no worries, the way in which platform types are aliased can be a bit confusing

SirNapkin1334

05/11/2021, 12:57 AM

my question is, why they don't use the java implementation of that if it's available

i benchmarked it and the speedup is on the order of 5x

ephemient

05/11/2021, 12:58 AM

kotlin-stdlib-jvm only depends on Java 6

💯 1

SirNapkin1334

05/11/2021, 12:59 AM

6 Views