Troubleshooting

Setup

Opening the project in IntelliJ

Incorrect JDK

File | Project Structure | Project Settings | Project

SDK: and Language level: are set to a valid jdk (19+)

Broken Gradle

View | Tool Windows | Gradle (also the elephant icon on the right-hand bar)

Press the Reload All Gradle Project button.

Running with Gradle Wrapper

> Kotlin could not find the required JDK tools in the Java installation. Make sure Kotlin compilation is running on a JDK, not JRE.

Open the gradle.properties file, remove the hash from the first line and replace the directory with the location of your JDK installation.

org.gradle.java.home=C:/Users/Greg/.jdks/openjdk-19.0.1/