IntelliJ IDEA

IntelliJ's Gradle integration allows running Gradle tasks with debugging out of the box, and it will automatically attach to the correct JVM.

Hot-swap

Many JVMs implement basic hot-swap support out of the box. However, the JetBrains runtime includes enhanced redefinition features such as adding and removing methods. See below for instructions to use the JetBrains runtime.

If you are using Shadow to relocate dependencies, you may need to disable relocations or create a separate artifact without relocations for hot-swap to work properly.

settings.gradle.kts

plugins {
  // add toolchain resolver
  id("org.gradle.toolchains.foojay-resolver-convention") version "0.9.0"
}

build.gradle.kts

tasks.withType(xyz.jpenilla.runtask.task.AbstractRun::class) {
  javaLauncher = javaToolchains.launcherFor { 
    vendor = JvmVendorSpec.JETBRAINS
    languageVersion = JavaLanguageVersion.of(21)
  }
  jvmArgs("-XX:+AllowEnhancedClassRedefinition")
}