Use platform class loader in 'kotlin' runner on JDK 9+

#KT-46312 Fixed

compiler/cli/cli-runner/src/org/jetbrains/kotlin/runner/runners.kt

@@ -84,30 +84,24 @@ abstract class AbstractRunner : Runner {
 
 class MainClassRunner(override val className: String) : AbstractRunner() {
     override fun createClassLoader(classpath: List<URL>): ClassLoader =
-            URLClassLoader(classpath.toTypedArray(), null)
+        URLClassLoader(classpath.toTypedArray(), getPlatformClassLoader())
 }
 
 class JarRunner(private val path: String) : AbstractRunner() {
     override val className: String =
-            try {
-                val jar = JarFile(path)
-                try {
-                    jar.manifest.mainAttributes.getValue(Attributes.Name.MAIN_CLASS)
-                }
-                finally {
-                    jar.close()
-                }
+        try {
+            JarFile(path).use { jar ->
+                jar.manifest.mainAttributes.getValue(Attributes.Name.MAIN_CLASS)
             }
-            catch (e: IOException) {
-                throw RunnerException("could not read manifest from " + path + ": " + e.message)
-            }
-            ?: throw RunnerException("no Main-Class entry found in manifest in $path")
+        } catch (e: IOException) {
+            throw RunnerException("could not read manifest from " + path + ": " + e.message)
+        } ?: throw RunnerException("no Main-Class entry found in manifest in $path")
 
     override fun createClassLoader(classpath: List<URL>): ClassLoader {
         // 'kotlin *.jar' ignores the passed classpath as 'java -jar' does
         // TODO: warn on non-empty classpath?
 
-        return URLClassLoader(arrayOf(File(path).toURI().toURL()), null)
+        return URLClassLoader(arrayOf(File(path).toURI().toURL()), getPlatformClassLoader())
     }
 }
 
@@ -176,3 +170,10 @@ class ExpressionRunner(private val code: String) : RunnerWithCompiler() {
         runCompiler(compilerClasspath, compilerArgs)
     }
 }
+
+private fun getPlatformClassLoader(): ClassLoader? =
+    try {
+        ClassLoader::class.java.getDeclaredMethod("getPlatformClassLoader")?.invoke(null) as? ClassLoader?
+    } catch (_: Exception) {
+        null
+    }

compiler/testData/launcher/jdkModuleUsage.kt

@@ -0,0 +1,7 @@
+package test
+
+import java.sql.Driver
+
+fun main() {
+    println(Driver::class.java)
+}

compiler/tests/org/jetbrains/kotlin/cli/LauncherScriptTest.kt

@@ -444,4 +444,31 @@ println(42)
             workDirectory = subDir
         )
     }
+
+    fun testKotlinUseJdkModuleFromMainClass() {
+        val jdk11 = mapOf("JAVA_HOME" to KtTestUtil.getJdk11Home().absolutePath)
+        runProcess(
+            "kotlinc", "$testDataDirectory/jdkModuleUsage.kt", "-d", tmpdir.path,
+            environment = jdk11,
+        )
+        runProcess(
+            "kotlin", "-cp", tmpdir.path, "test.JdkModuleUsageKt",
+            expectedStdout = "interface java.sql.Driver\n",
+            environment = jdk11,
+        )
+    }
+
+    fun testKotlinUseJdkModuleFromJar() {
+        val jdk11 = mapOf("JAVA_HOME" to KtTestUtil.getJdk11Home().absolutePath)
+        val output = tmpdir.resolve("out.jar")
+        runProcess(
+            "kotlinc", "$testDataDirectory/jdkModuleUsage.kt", "-d", output.path,
+            environment = jdk11,
+        )
+        runProcess(
+            "kotlin", output.path,
+            expectedStdout = "interface java.sql.Driver\n",
+            environment = jdk11,
+        )
+    }
 }

plugins/scripting/scripting-compiler/src/org/jetbrains/kotlin/scripting/compiler/plugin/JvmCliScriptEvaluationExtension.kt

@@ -51,7 +51,7 @@ class JvmCliScriptEvaluationExtension : AbstractScriptEvaluationExtension() {
 
 private fun getPlatformClassLoader(): ClassLoader? =
     try {
-        ClassLoader::class.java.getDeclaredMethod("getPlatformClassLoader")?.invoke(null)?.let { it as? ClassLoader }
+        ClassLoader::class.java.getDeclaredMethod("getPlatformClassLoader")?.invoke(null) as? ClassLoader?
     } catch (_: Exception) {
         null
     }