build.gradle

plugins {
    id 'java'
    id 'java-library'
    id 'org.jetbrains.kotlin.jvm' version '1.5.0'
}

group 'com.example' //Not my actual group ID
version '1.0-SNAPSHOT'


test {
    useJUnit()
}

java {
    modularity.inferModulePath = true
}

tasks.named('compileJava') {
    modularity.inferModulePath = true
    options.javaModuleVersion = provider { project.version }
}

dependencies {
    compile 'org.jetbrains:annotations:20.1.0'
    compile 'org.ow2.asm:asm:9.1'
    compile 'org.ow2.asm:asm-util:9.1'
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"

    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.6.0'
    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine'
}


subprojects {

    apply plugin: 'kotlin'


    dependencies {

        compile "org.jetbrains.kotlin:kotlin-stdlib-jdk8"

    }

    sourceCompatibility = 1.11
    targetCompatibility = 1.11

    compileKotlin {
        kotlinOptions.jvmTarget = "1.11"
    }
    compileTestKotlin {
        kotlinOptions.jvmTarget = "1.11"
    }

}

settings.gradle

rootProject.name = 'mixin-utils'

include 'base.test'

//subProject('base.test') //Uncommenting to provide a path to the project directory

private String[] subProject(String... names) {
    for (int i = 0; i < names.length; i++) {
        project(names[i]).projectDir = new File("${rootDir.absolutePath}${File.separator}src${File.separator}${names[i]}")
    }
    return names
}

structure.txt

src
   module1 (setup as a IJ module)
      kotlin (setup as IJ sources)
         example.packages
         module-info.java
   module2 (setup as a IJ module)
      kotlin (setup as IJ sources)
         example.packages
         module-info.java
settings.gradle
build.gradle