[Kotlin] Kotlin 소스 파일 컴파일하여 Class 객체로 로딩하기

build.gradle.kts

implementation("org.jetbrains.kotlin:kotlin-compiler:1.8.21")

KotlinFileClassLoader

import org.jetbrains.kotlin.cli.common.arguments.K2JVMCompilerArguments
import org.jetbrains.kotlin.cli.common.messages.MessageRenderer
import org.jetbrains.kotlin.cli.common.messages.PrintingMessageCollector
import org.jetbrains.kotlin.cli.jvm.K2JVMCompiler
import org.jetbrains.kotlin.config.Services
import java.io.File
import java.net.URLClassLoader
import java.util.regex.Pattern

class KotlinFileClassLoader

fun main(args: Array<String>) {
    val kotlinFiles = listOf(
        File("/Users/demo-user/IdeaProjects/demo-project/src/main/kotlin/com/example/demo/DemoApplication.kt"),
        File("/Users/demo-user/IdeaProjects/demo-project/src/main/kotlin/com/example/demo/model/Demo.kt")
    )

    val classes = compileKotlinFiles(kotlinFiles)

    classes.forEach { println("${it.packageName}.${it.name}") }
}

fun compileKotlinFiles(kotlinFiles: List<File>): List<Class<*>> {
    val outDir = File("out")
    val arguments = K2JVMCompilerArguments().apply {
        freeArgs = kotlinFiles.map { it.absolutePath }
        classpath = System.getProperty("java.class.path")
        destination = outDir.absolutePath
    }

    val collector = PrintingMessageCollector(System.err, MessageRenderer.PLAIN_RELATIVE_PATHS, arguments.verbose)
    val compiler = K2JVMCompiler()
    val exitCode = compiler.exec(collector, Services.EMPTY, arguments)

    return URLClassLoader(arrayOf(outDir.toURI().toURL())).use { classLoader ->
        kotlinFiles
            .asSequence()
            .map { it.absolutePath }
            .map { Pattern.compile("src/main/kotlin/(.*)").matcher(it) }
            .filter { it.find() }
            .map { it.group(1) }
            .map { it.replace("/", ".") }
            .map { it.replace(".kt", "") }
            .map { packageName: String -> classLoader.loadClass(packageName) }
            .toList()
    }
}