Trouble with Gradle and Junit


#1

I wanted to get started but I’m having trouble combining kotlin with gradle and Junit.

For all of these repositories, ‘gradle build’ gives an error:

Given that all these are failing, I’m guessing something is wrong with my installation.
I am using:

  • “kotlin -version” -> “Kotlin version 1.2.21-release-88 (JRE 9.0.4+11)”
  • “gradle --version” -> “Gradle 4.5… 9.0.4”
  • “java -version” -> “openjdk version “9-internal””
  • “javac -version” -> “javac 9-internal”
  • ubuntu 16.04

Could someone try to run one of these repos, and if it works, what their setup is.


#2

Please install Oracle JDK 8. I’m not sure what exactly the “9-internal” version of OpenJDK is, but obviously it doesn’t work properly.


#3

I believe OpenJDK ‘9-internal’ is what newer versions of Ubuntu install if you run this command:

sudo apt-get install default-jdk

The errors are most likely the result of missing module exports.
For instance java.lang.NoClassDefFoundError: sun/reflect/ConstructorAccessor can be fixed if java is run with the following switch:
--add-exports java.base/sun.reflect=ALL-UNNAMED

Determining which module exports are missing and adding appropriate switches is somewhat time consuming so I would recommend installing Java 8 and setting it up as default as the best solution to your issues - exactly like @yole said :slight_smile: