Introduce Java support in JVM MPP targets (KT-26256)

Deprecate the `jvmWithJava` preset, add warning.

Add a function `withJava()` to JVM MPP targets which applies the 'java'
plugin and sets up the Kotlin & Java interoperation.

Issue #KT-26256 Fixed

Signed-off-by: Sergey Igushkin <hotkeytlt@gmail.com>

libraries/tools/kotlin-gradle-plugin-dsl-codegen/src/main/kotlin/org/jetbrains/kotlin/generators/gradle/dsl/presetEntries.kt

@@ -21,22 +21,17 @@ internal const val MPP_PACKAGE = "org.jetbrains.kotlin.gradle.plugin.mpp"
 internal const val KOTLIN_NATIVE_TARGET_PRESET_CLASS_FQNAME = "$MPP_PACKAGE.KotlinNativeTargetPreset"
 internal const val KOTLIN_NATIVE_TARGET_CLASS_FQNAME = "$MPP_PACKAGE.KotlinNativeTarget"
 
-private const val KOTLIN_ONLY_TARGET_CLASS_FQNAME = "$MPP_PACKAGE.KotlinOnlyTarget"
-
 internal val jvmPresetEntry = KotlinPresetEntry(
     "jvm",
     typeName("$MPP_PACKAGE.KotlinJvmTargetPreset"),
-    typeName(
+    typeName("org.jetbrains.kotlin.gradle.targets.jvm.KotlinJvmTarget")
-        KOTLIN_ONLY_TARGET_CLASS_FQNAME,
-        "$MPP_PACKAGE.KotlinJvmCompilation"
-    )
 )
 
 internal val jsPresetEntry = KotlinPresetEntry(
     "js",
     typeName("$MPP_PACKAGE.KotlinJsTargetPreset"),
     typeName(
-        KOTLIN_ONLY_TARGET_CLASS_FQNAME,
+        "$MPP_PACKAGE.KotlinOnlyTarget",
         "$MPP_PACKAGE.KotlinJsCompilation"
     )
 )

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/kotlin/org/jetbrains/kotlin/gradle/NewMultiplatformIT.kt

@@ -5,11 +5,13 @@
 package org.jetbrains.kotlin.gradle
 
 import org.jetbrains.kotlin.gradle.plugin.ProjectLocalConfigurations
+import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinJvmWithJavaTargetPreset
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinMultiplatformPlugin
 import org.jetbrains.kotlin.gradle.plugin.mpp.NativeOutputKind
 import org.jetbrains.kotlin.gradle.plugin.mpp.UnusedSourceSetsChecker
 import org.jetbrains.kotlin.gradle.plugin.sources.METADATA_CONFIGURATION_NAME_SUFFIX
 import org.jetbrains.kotlin.gradle.plugin.sources.SourceSetConsistencyChecks
+import org.jetbrains.kotlin.gradle.targets.jvm.KotlinJvmTarget
 import org.jetbrains.kotlin.gradle.util.*
 import org.jetbrains.kotlin.konan.target.CompilerOutputKind
 import org.jetbrains.kotlin.konan.target.HostManager
@@ -299,52 +301,131 @@ class NewMultiplatformIT : BaseGradleIT() {
     }
 
     @Test
-    fun testJvmWithJavaEquivalence() = with(Project("sample-lib", gradleVersion, "new-mpp-lib-and-app")) {
+    fun testJvmWithJavaEquivalence() = doTestJvmWithJava(testJavaSupportInJvmTargets = false)
-        lateinit var classesWithoutJava: Set<String>
 
-        fun getFilePathsSet(inDirectory: String): Set<String> {
+    @Test
-            val dir = projectDir.resolve(inDirectory)
+    fun testJavaSupportInJvmTargets() = doTestJvmWithJava(testJavaSupportInJvmTargets = true)
-            return dir.walk().filter { it.isFile }.map { it.relativeTo(dir).path.replace('\\', '/') }.toSet()
-        }
 
-        build("assemble") {
+    private fun doTestJvmWithJava(testJavaSupportInJvmTargets: Boolean) =
-            assertSuccessful()
+        with(Project("sample-lib", GradleVersionRequired.AtLeast("5.0"), "new-mpp-lib-and-app")) {
-            classesWithoutJava = getFilePathsSet("build/classes")
+            lateinit var classesWithoutJava: Set<String>
-        }
 
-        gradleBuildScript().modify {
+            fun getFilePathsSet(inDirectory: String): Set<String> {
-            it.replace("presets.jvm", "presets.jvmWithJava").replace("jvm(", "targetFromPreset(presets.jvmWithJava, ")
+                val dir = projectDir.resolve(inDirectory)
-        }
+                return dir.walk().filter { it.isFile }.map { it.relativeTo(dir).invariantSeparatorsPath }.toSet()
+            }
 
-        projectDir.resolve("src/main/java").apply {
+            build("assemble") {
-            mkdirs()
+                assertSuccessful()
-            mkdir()
+                classesWithoutJava = getFilePathsSet("build/classes")
-            // Check that Java can access the dependencies (kotlin-stdlib):
+            }
-            resolve("JavaClassInJava.java").writeText("""
+
-                package com.example.lib;
+            gradleBuildScript().modify {
-                import kotlin.sequences.Sequence;
+                if (testJavaSupportInJvmTargets) {
-                class JavaClassInJava {
+                    it + "\nkotlin.jvm(\"jvm6\").${KotlinJvmTarget::withJava.name}()"
-                    Sequence<String> makeSequence() { throw new UnsupportedOperationException(); }
+                } else {
+                    it.replace("presets.jvm", "presets.jvmWithJava").replace("jvm(", "targetFromPreset(presets.jvmWithJava, ")
+                }.plus(
+                    "\n" + """
+                    buildscript {
+                        repositories {
+                            maven { url 'https://plugins.gradle.org/m2/' }
+                        }
+                        dependencies {
+                            classpath 'com.github.jengelman.gradle.plugins:shadow:5.0.0'
+                        }
+                    }
+                    
+                    apply plugin: 'com.github.johnrengelman.shadow'
+                    apply plugin: 'application'
+                    
+                    mainClassName = 'com.example.lib.CommonKt'
+                    """.trimIndent()
+                )
+            }
+
+            fun javaSourceRootForCompilation(compilationName: String) =
+                if (testJavaSupportInJvmTargets) "src/jvm6${compilationName.capitalize()}/java" else "src/$compilationName/java"
+
+            val javaMainSrcDir = javaSourceRootForCompilation("main")
+            val javaTestSrcDir = javaSourceRootForCompilation("test")
+
+            projectDir.resolve(javaMainSrcDir).apply {
+                mkdirs()
+                // Check that Java can access the dependencies (kotlin-stdlib):
+                resolve("JavaClassInJava.java").writeText(
+                    """
+                    package com.example.lib;
+                    import kotlin.sequences.Sequence;
+                    class JavaClassInJava {
+                        Sequence<String> makeSequence() { throw new UnsupportedOperationException(); }
+                    }
+                    """.trimIndent()
+                )
+
+                // Add a Kotlin source file in the Java source root and check that it is compiled:
+                resolve("KotlinClassInJava.kt").writeText(
+                    """
+                    package com.example.lib
+                    class KotlinClassInJava
+                    """.trimIndent()
+                )
+            }
+
+            projectDir.resolve(javaTestSrcDir).apply {
+                mkdirs()
+                resolve("JavaTest.java").writeText(
+                    """
+                    package com.example.lib;
+                    import org.junit.*;
+                    public class JavaTest {
+                        @Test
+                        public void testAccessKotlin() {
+                            MainKt.expectedFun();
+                            MainKt.x();
+                            new KotlinClassInJava();
+                            new JavaClassInJava();
+                        }
+                    }
+                    """.trimIndent()
+                )
+            }
+
+            build("clean", "build", "run", "shadowJar") {
+                assertSuccessful()
+                val expectedMainClasses =
+                    classesWithoutJava + setOf(
+                        "kotlin/jvm6/main/com/example/lib/KotlinClassInJava.class",
+                        "java/main/com/example/lib/JavaClassInJava.class",
+                        "java/test/com/example/lib/JavaTest.class"
+                    )
+                val actualClasses = getFilePathsSet("build/classes")
+                Assert.assertEquals(expectedMainClasses, actualClasses)
+
+                val jvmTestTaskName = if (testJavaSupportInJvmTargets) "jvm6Test" else "test"
+                assertTasksExecuted(":$jvmTestTaskName")
+                assertFileExists("build/reports/tests/$jvmTestTaskName/classes/com.example.lib.JavaTest.html")
+
+                if (testJavaSupportInJvmTargets) {
+                    assertNotContains(KotlinJvmWithJavaTargetPreset.DEPRECATION_WARNING)
+                } else {
+                    assertContains(KotlinJvmWithJavaTargetPreset.DEPRECATION_WARNING)
                 }
-            """.trimIndent())
 
-            // Add a Kotlin source file in the Java source root and check that it is compiled:
+                assertTasksExecuted(":run")
-            resolve("KotlinClassInJava.kt").writeText("""
+                assertContains(">>> Common.kt >>> main()")
-                package com.example.lib
-                class KotlinClassInJava
-            """.trimIndent())
-        }
 
-        build("clean", "assemble") {
+                assertTasksExecuted(":shadowJar")
-            assertSuccessful()
+                val entries = ZipFile(projectDir.resolve("build/libs/sample-lib-1.0-all.jar")).use { zip ->
-            val expectedClasses =
+                    zip.entries().asSequence().map { it.name }.toSet()
-                classesWithoutJava +
+                }
-                        "kotlin/jvm6/main/com/example/lib/KotlinClassInJava.class" +
+                assertTrue { "kotlin/Pair.class" in entries }
-                        "java/main/com/example/lib/JavaClassInJava.class"
+                assertTrue { "com/example/lib/CommonKt.class" in entries }
-            val actualClasses = getFilePathsSet("build/classes")
+                assertTrue { "com/example/lib/MainKt.class" in entries }
-            Assert.assertEquals(expectedClasses, actualClasses)
+                assertTrue { "com/example/lib/JavaClassInJava.class" in entries }
+                assertTrue { "com/example/lib/KotlinClassInJava.class" in entries }
+            }
         }
-    }
 
     @Test
     fun testLibWithTests() = doTestLibWithTests(Project("new-mpp-lib-with-tests", gradleVersion))

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/new-mpp-lib-and-app/sample-lib/build.gradle

@@ -63,12 +63,23 @@ kotlin {
                 api 'org.jetbrains.kotlin:kotlin-stdlib-common'
             }
         }
+        commonTest {
+            dependencies {
+                implementation kotlin("test-common")
+                implementation kotlin("test-annotations-common")
+            }
+        }
         jvm6Main {
             dependencies {
                 api 'org.jetbrains.kotlin:kotlin-stdlib'
                 implementation 'org.jetbrains.kotlinx:kotlinx-coroutines-core:0.23.4'
             }
         }
+        jvm6Test {
+            dependencies {
+                implementation kotlin("test-junit")
+            }
+        }
         nodeJsMain {
         	dependencies {
                 api 'org.jetbrains.kotlin:kotlin-stdlib-js'

libraries/tools/kotlin-gradle-plugin-integration-tests/src/test/resources/testProject/new-mpp-lib-and-app/sample-lib/src/commonMain/kotlin/Common.kt

@@ -3,3 +3,7 @@ package com.example.lib
 fun <T> id(t: T): T = t
 
 expect fun expectedFun(): Unit
+
+fun main() {
+    println(">>> Common.kt >>> main()")
+}

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/dsl/KotlinTargetContainerWithPresetFunctions.kt

@@ -7,11 +7,11 @@ import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinAndroidTarget
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinAndroidTargetPreset
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinJsCompilation
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinJsTargetPreset
-import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinJvmCompilation
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinJvmTargetPreset
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinNativeTarget
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinNativeTargetPreset
 import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinOnlyTarget
+import org.jetbrains.kotlin.gradle.targets.jvm.KotlinJvmTarget
 
 // DO NOT EDIT MANUALLY! Generated by org.jetbrains.kotlin.generators.gradle.dsl.MppPresetFunctionsCodegenKt
 
@@ -19,8 +19,8 @@ interface KotlinTargetContainerWithPresetFunctions : KotlinTargetsContainerWithP
 
     fun jvm(
         name: String = "jvm",
-        configure: KotlinOnlyTarget<KotlinJvmCompilation>.() -> Unit = { }
+        configure: KotlinJvmTarget.() -> Unit = { }
-    ): KotlinOnlyTarget<KotlinJvmCompilation> =
+    ): KotlinJvmTarget =
         configureOrCreate(
             name,
             presets.getByName("jvm") as KotlinJvmTargetPreset,

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/KotlinPlugin.kt

@@ -2,6 +2,7 @@ package org.jetbrains.kotlin.gradle.plugin
 
 import com.android.build.gradle.BaseExtension
 import com.android.build.gradle.BasePlugin
+import com.android.build.gradle.api.AndroidSourceSet
 import com.android.build.gradle.api.BaseVariant
 import com.android.builder.model.SourceProvider
 import groovy.lang.Closure
@@ -430,8 +431,9 @@ internal abstract class AbstractKotlinPlugin(
             jarTask.dependsOn(inspectTask.getTaskOrProvider())
         }
 
-        private fun setUpJavaSourceSets(
+        internal fun setUpJavaSourceSets(
-            kotlinTarget: KotlinWithJavaTarget<*>
+            kotlinTarget: KotlinTarget,
+            duplicateJavaSourceSetsAsKotlinSourceSets: Boolean = true
         ) {
             val project = kotlinTarget.project
             val javaSourceSets = project.convention.getPlugin(JavaPluginConvention::class.java).sourceSets
@@ -442,22 +444,27 @@ internal abstract class AbstractKotlinPlugin(
             }
 
             // Workaround for indirect mutual recursion between the two `all { ... }` handlers:
-            val compilationsUnderConstruction = mutableMapOf<String, KotlinWithJavaCompilation<*>>()
+            val compilationsUnderConstruction = mutableMapOf<String, KotlinCompilation<*>>()
 
             javaSourceSets.all { javaSourceSet ->
                 val kotlinCompilation =
                     compilationsUnderConstruction[javaSourceSet.name] ?: kotlinTarget.compilations.maybeCreate(javaSourceSet.name)
-                kotlinCompilation.javaSourceSet = javaSourceSet
+                (kotlinCompilation as? KotlinWithJavaCompilation<*>)?.javaSourceSet = javaSourceSet
-                val kotlinSourceSet = project.kotlinExtension.sourceSets.maybeCreate(kotlinCompilation.name)
+
-                javaSourceSet.addConvention(kotlinSourceSetDslName, kotlinSourceSet)
+                if (duplicateJavaSourceSetsAsKotlinSourceSets) {
-                kotlinSourceSet.kotlin.source(javaSourceSet.java)
+                    val kotlinSourceSet = project.kotlinExtension.sourceSets.maybeCreate(kotlinCompilation.name)
-                kotlinCompilation.source(kotlinSourceSet)
+                    kotlinSourceSet.kotlin.source(javaSourceSet.java)
+                    kotlinCompilation.source(kotlinSourceSet)
+                    javaSourceSet.addConvention(kotlinSourceSetDslName, kotlinSourceSet)
+                } else {
+                    javaSourceSet.addConvention(kotlinSourceSetDslName, kotlinCompilation.defaultSourceSet)
+                }
             }
 
             kotlinTarget.compilations.all { kotlinCompilation ->
                 val sourceSetName = kotlinCompilation.name
                 compilationsUnderConstruction[sourceSetName] = kotlinCompilation
-                kotlinCompilation.javaSourceSet = javaSourceSets.maybeCreate(sourceSetName)
+                (kotlinCompilation as? KotlinWithJavaCompilation<*>)?.javaSourceSet = javaSourceSets.maybeCreate(sourceSetName)
 
                 // Another Kotlin source set following the other convention, named according to the compilation, not the Java source set:
                 val kotlinSourceSet = project.kotlinExtension.sourceSets.maybeCreate(kotlinCompilation.defaultSourceSetName)

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/KotlinTargetConfigurator.kt

@@ -301,6 +301,9 @@ internal val KotlinCompilation<*>.deprecatedCompileConfigurationName: String
 internal val KotlinCompilationToRunnableFiles<*>.deprecatedRuntimeConfigurationName: String
     get() = disambiguateName("runtime")
 
+internal val KotlinTarget.testTaskName: String
+    get() = lowerCamelCaseName(targetName, AbstractKotlinTargetConfigurator.testTaskNameSuffix)
+
 abstract class KotlinTargetConfigurator<KotlinCompilationType : KotlinCompilation<*>>(
     createDefaultSourceSets: Boolean,
     createTestCompilation: Boolean,

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/plugin/mpp/kotlinTargetPresets.kt

@@ -6,20 +6,25 @@
 package org.jetbrains.kotlin.gradle.plugin.mpp
 
 import org.gradle.api.Project
-import org.jetbrains.kotlin.gradle.plugin.*
+import org.jetbrains.kotlin.gradle.plugin.KotlinCompilation
+import org.jetbrains.kotlin.gradle.plugin.KotlinPlatformType
+import org.jetbrains.kotlin.gradle.plugin.KotlinTargetConfigurator
+import org.jetbrains.kotlin.gradle.plugin.KotlinTargetPreset
 
-abstract class KotlinOnlyTargetPreset<T : KotlinCompilation<*>>(
+abstract class KotlinOnlyTargetPreset<R : KotlinOnlyTarget<T>, T : KotlinCompilation<*>>(
     protected val project: Project,
     protected val kotlinPluginVersion: String
-) : KotlinTargetPreset<KotlinOnlyTarget<T>> {
+) : KotlinTargetPreset<R> {
 
     protected abstract fun createKotlinTargetConfigurator(): KotlinTargetConfigurator<T>
 
     protected open fun provideTargetDisambiguationClassifier(target: KotlinOnlyTarget<T>): String? =
         target.targetName
 
-    override fun createTarget(name: String): KotlinOnlyTarget<T> {
+    abstract protected fun instantiateTarget(): R
-        val result = KotlinOnlyTarget<T>(project, platformType).apply {
+
+    override fun createTarget(name: String): R {
+        val result = instantiateTarget().apply {
             targetName = name
             disambiguationClassifier = provideTargetDisambiguationClassifier(this@apply)
             preset = this@KotlinOnlyTargetPreset

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/js/KotlinJsTargetPreset.kt

@@ -13,10 +13,12 @@ import org.jetbrains.kotlin.gradle.targets.js.KotlinJsTargetConfigurator
 open class KotlinJsTargetPreset(
     project: Project,
     kotlinPluginVersion: String
-) : KotlinOnlyTargetPreset<KotlinJsCompilation>(
+) : KotlinOnlyTargetPreset<KotlinOnlyTarget<KotlinJsCompilation>, KotlinJsCompilation>(
     project,
     kotlinPluginVersion
 ) {
+    override fun instantiateTarget() = KotlinOnlyTarget<KotlinJsCompilation>(project, KotlinPlatformType.js)
+
     override fun createKotlinTargetConfigurator() = KotlinJsTargetConfigurator(kotlinPluginVersion)
 
     override fun getName(): String = PRESET_NAME

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/jvm/KotlinJvmTarget.kt

@@ -0,0 +1,162 @@
+/*
+ * Copyright 2010-2019 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.gradle.targets.jvm
+
+import org.gradle.api.InvalidUserCodeException
+import org.gradle.api.Project
+import org.gradle.api.file.ConfigurableFileCollection
+import org.gradle.api.plugins.JavaPlugin
+import org.gradle.api.plugins.JavaPluginConvention
+import org.gradle.api.tasks.SourceSet
+import org.gradle.api.tasks.compile.AbstractCompile
+import org.gradle.api.tasks.testing.Test
+import org.gradle.jvm.tasks.Jar
+import org.jetbrains.kotlin.gradle.dsl.multiplatformExtension
+import org.jetbrains.kotlin.gradle.plugin.*
+import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinJvmCompilation
+import org.jetbrains.kotlin.gradle.plugin.mpp.KotlinOnlyTarget
+import org.jetbrains.kotlin.gradle.utils.addExtendsFromRelation
+import java.util.concurrent.Callable
+
+class KotlinJvmTarget(
+    project: Project
+) : KotlinOnlyTarget<KotlinJvmCompilation>(
+    project, KotlinPlatformType.jvm
+) {
+    var withJavaEnabled = false
+        private set
+
+    @Suppress("unused") // user DSL
+    fun withJava() {
+        project.multiplatformExtension.targets.find { it is KotlinJvmTarget && it.withJavaEnabled }
+            ?.let { existingJavaTarget ->
+                throw InvalidUserCodeException(
+                    "Only one of the JVM targets can be configured to work with Java. The target '${existingJavaTarget.name}' is " +
+                            "already set up to work with Java; cannot setup another target '$targetName'"
+                )
+            }
+
+        withJavaEnabled = true
+
+        project.plugins.apply(JavaPlugin::class.java)
+        val javaPluginConvention = project.convention.getPlugin(JavaPluginConvention::class.java)
+        AbstractKotlinPlugin.setUpJavaSourceSets(this, duplicateJavaSourceSetsAsKotlinSourceSets = false)
+
+        // Below, some effort is made to ensure that a user or 3rd-party plugin that inspects or interacts
+        // with the entities created by the Java plugin, not knowing of the existence of the Kotlin plugin,
+        // sees 'the right picture' of the inputs and outputs, for example:
+        // * the relevant dependencies for Java and Kotlin are in sync,
+        // * the Java outputs contain the outputs produced by Kotlin as well
+
+        javaPluginConvention.sourceSets.all { javaSourceSet ->
+            val compilation = compilations.getByName(javaSourceSet.name)
+            val compileJavaTask = project.tasks.getByName(javaSourceSet.compileJavaTaskName) as AbstractCompile
+            configureJavaTask(compilation.compileKotlinTask, compileJavaTask, project.logger)
+
+            setupJavaSourceSetSourcesAndResources(javaSourceSet, compilation)
+
+            val javaClasses = project.files(Callable { compileJavaTask.destinationDir }).builtBy(compileJavaTask)
+
+            compilation.output.classesDirs.from(javaClasses)
+
+            (javaSourceSet.output.classesDirs as? ConfigurableFileCollection)?.from(
+                compilation.output.classesDirs.minus(javaClasses)
+            )
+
+            javaSourceSet.output.setResourcesDir(Callable { compilation.output.resourcesDirProvider })
+
+            setupDependenciesCrossInclusionForJava(compilation, javaSourceSet)
+        }
+
+        // Eliminate the Java output configurations from dependency resolution to avoid ambiguity between them and
+        // the equivalent configurations created for the target:
+        listOf(JavaPlugin.API_ELEMENTS_CONFIGURATION_NAME, JavaPlugin.RUNTIME_ELEMENTS_CONFIGURATION_NAME)
+            .forEach { outputConfigurationName ->
+                project.configurations.findByName(outputConfigurationName)?.isCanBeConsumed = false
+            }
+
+        disableJavaPluginTasks(javaPluginConvention)
+    }
+
+    private fun setupJavaSourceSetSourcesAndResources(
+        javaSourceSet: SourceSet,
+        compilation: KotlinJvmCompilation
+    ) {
+        javaSourceSet.java.setSrcDirs(listOf("src/${compilation.defaultSourceSet.name}/java"))
+        compilation.defaultSourceSet.kotlin.srcDirs(javaSourceSet.java.sourceDirectories)
+
+        // To avoid confusion in the sources layout, remove the default Java source directories
+        // (like src/main/java, src/test/java) and instead add sibling directories to those where the Kotlin
+        // sources are placed (i.e. src/jvmMain/java, src/jvmTest/java):
+        javaSourceSet.resources.setSrcDirs(compilation.defaultSourceSet.resources.sourceDirectories)
+        compilation.defaultSourceSet.resources.srcDirs(javaSourceSet.resources.sourceDirectories)
+
+        // Resources processing is done with the Kotlin resource processing task:
+        val processJavaResourcesTask = project.tasks.getByName(javaSourceSet.processResourcesTaskName)
+        processJavaResourcesTask.dependsOn(project.tasks.getByName(compilation.processResourcesTaskName))
+        processJavaResourcesTask.enabled = false
+    }
+
+    private fun disableJavaPluginTasks(javaPluginConvention: JavaPluginConvention) {
+        // A 'normal' build should not do redundant job like running the tests twice or building two JARs,
+        // so disable some tasks and just make them depend on the others:
+        val targetJar = project.tasks.getByName(artifactsTaskName) as Jar
+        val javaJar = project.tasks.getByName(javaPluginConvention.sourceSets.getByName("main").jarTaskName) as Jar
+        (javaJar.source as? ConfigurableFileCollection)?.setFrom(targetJar.source)
+        javaJar.conventionMapping("archiveName") { targetJar.archiveName }
+        javaJar.dependsOn(targetJar)
+        javaJar.enabled = false
+
+        val javaTestTask = project.tasks.getByName(JavaPlugin.TEST_TASK_NAME) as Test
+        javaTestTask.dependsOn(project.tasks.getByName(testTaskName) as Test)
+        javaTestTask.enabled = false
+    }
+
+    private fun setupDependenciesCrossInclusionForJava(
+        compilation: KotlinJvmCompilation,
+        javaSourceSet: SourceSet
+    ) {
+        // Make sure Kotlin compilation dependencies appear in the Java source set classpaths:
+
+        listOf(
+            compilation.apiConfigurationName,
+            compilation.implementationConfigurationName,
+            compilation.compileOnlyConfigurationName,
+            compilation.deprecatedCompileConfigurationName
+        ).forEach { configurationName ->
+            project.addExtendsFromRelation(javaSourceSet.compileClasspathConfigurationName, configurationName)
+        }
+
+        listOf(
+            compilation.apiConfigurationName,
+            compilation.implementationConfigurationName,
+            compilation.runtimeOnlyConfigurationName,
+            compilation.deprecatedRuntimeConfigurationName
+        ).forEach { configurationName ->
+            project.addExtendsFromRelation(javaSourceSet.runtimeClasspathConfigurationName, configurationName)
+        }
+
+        // Add the Java source set dependencies to the Kotlin compilation compile & runtime configurations:
+
+        listOfNotNull(
+            javaSourceSet.compileConfigurationName,
+            javaSourceSet.compileOnlyConfigurationName,
+            javaSourceSet.apiConfigurationName.takeIf { project.configurations.findByName(it) != null },
+            javaSourceSet.implementationConfigurationName
+        ).forEach { configurationName ->
+            project.addExtendsFromRelation(compilation.compileDependencyConfigurationName, configurationName)
+        }
+
+        listOfNotNull(
+            javaSourceSet.runtimeConfigurationName,
+            javaSourceSet.runtimeOnlyConfigurationName,
+            javaSourceSet.apiConfigurationName.takeIf { project.configurations.findByName(it) != null },
+            javaSourceSet.implementationConfigurationName
+        ).forEach { configurationName ->
+            project.addExtendsFromRelation(compilation.runtimeDependencyConfigurationName, configurationName)
+        }
+    }
+}

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/jvm/KotlinJvmTargetPreset.kt

@@ -7,20 +7,19 @@
 package org.jetbrains.kotlin.gradle.plugin.mpp
 
 import org.gradle.api.Project
-import org.jetbrains.kotlin.gradle.plugin.Kotlin2JvmSourceSetProcessor
 import org.jetbrains.kotlin.gradle.plugin.KotlinPlatformType
-import org.jetbrains.kotlin.gradle.plugin.KotlinSourceSetProcessor
+import org.jetbrains.kotlin.gradle.targets.jvm.KotlinJvmTarget
-import org.jetbrains.kotlin.gradle.plugin.KotlinTargetConfigurator
 import org.jetbrains.kotlin.gradle.targets.jvm.KotlinJvmTargetConfigurator
-import org.jetbrains.kotlin.gradle.tasks.KotlinTasksProvider
 
 class KotlinJvmTargetPreset(
     project: Project,
     kotlinPluginVersion: String
-) : KotlinOnlyTargetPreset<KotlinJvmCompilation>(
+) : KotlinOnlyTargetPreset<KotlinJvmTarget, KotlinJvmCompilation>(
     project,
     kotlinPluginVersion
 ) {
+    override fun instantiateTarget(): KotlinJvmTarget = KotlinJvmTarget(project)
+
     override fun getName(): String = PRESET_NAME
 
     override fun createCompilationFactory(forTarget: KotlinOnlyTarget<KotlinJvmCompilation>): KotlinCompilationFactory<KotlinJvmCompilation> =

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/jvm/KotlinJvmWithJavaTargetPreset.kt

@@ -10,7 +10,9 @@ import org.gradle.api.Project
 import org.gradle.api.plugins.JavaPlugin
 import org.jetbrains.kotlin.gradle.dsl.KotlinJvmOptions
 import org.jetbrains.kotlin.gradle.plugin.*
+import org.jetbrains.kotlin.gradle.targets.jvm.KotlinJvmTarget
 import org.jetbrains.kotlin.gradle.tasks.KotlinTasksProvider
+import org.jetbrains.kotlin.gradle.utils.SingleWarningPerBuild
 
 class KotlinJvmWithJavaTargetPreset(
     private val project: Project,
@@ -20,6 +22,11 @@ class KotlinJvmWithJavaTargetPreset(
     override fun getName(): String = PRESET_NAME
 
     override fun createTarget(name: String): KotlinWithJavaTarget<KotlinJvmOptions> {
+        SingleWarningPerBuild.show(
+            project,
+            DEPRECATION_WARNING
+        )
+
         project.plugins.apply(JavaPlugin::class.java)
 
         val target = KotlinWithJavaTarget<KotlinJvmOptions>(project, KotlinPlatformType.jvm, name).apply {
@@ -50,5 +57,17 @@ class KotlinJvmWithJavaTargetPreset(
 
     companion object {
         const val PRESET_NAME = "jvmWithJava"
+
+        val DEPRECATION_WARNING = "\nThe 'jvmWithJava' preset is deprecated and will be removed soon. " +
+                "Please use an ordinary JVM target with Java support: \n\n" +
+                "    kotlin { \n" +
+                "        jvm { \n" +
+                "            ${KotlinJvmTarget::withJava.name}() \n" +
+                "        } \n" +
+                "    }\n\n" +
+                "After this change, please move the Java sources to the Kotlin source set directories. " +
+                "For example, if the JVM target is given the default name 'jvm':\n" +
+                " * instead of 'src/main/java', use 'src/jvmMain/java'\n" +
+                " * instead of 'src/test/java', use 'src/jvmTest/java'\n"
     }
 }

libraries/tools/kotlin-gradle-plugin/src/main/kotlin/org/jetbrains/kotlin/gradle/targets/metadata/KotlinMetadataTargetPreset.kt

@@ -9,18 +9,22 @@ package org.jetbrains.kotlin.gradle.plugin.mpp
 import org.gradle.api.Project
 import org.jetbrains.kotlin.gradle.dsl.KotlinCompile
 import org.jetbrains.kotlin.gradle.dsl.kotlinExtension
-import org.jetbrains.kotlin.gradle.plugin.*
+import org.jetbrains.kotlin.gradle.plugin.KotlinCompilation
+import org.jetbrains.kotlin.gradle.plugin.KotlinPlatformType
+import org.jetbrains.kotlin.gradle.plugin.KotlinSourceSet
+import org.jetbrains.kotlin.gradle.plugin.KotlinTargetConfigurator
 import org.jetbrains.kotlin.gradle.plugin.sources.applyLanguageSettingsToKotlinTask
 import org.jetbrains.kotlin.gradle.targets.metadata.KotlinMetadataTargetConfigurator
-import org.jetbrains.kotlin.gradle.tasks.KotlinTasksProvider
 
 class KotlinMetadataTargetPreset(
     project: Project,
     kotlinPluginVersion: String
-) : KotlinOnlyTargetPreset<KotlinCommonCompilation>(
+) : KotlinOnlyTargetPreset<KotlinOnlyTarget<KotlinCommonCompilation>, KotlinCommonCompilation>(
     project,
     kotlinPluginVersion
 ) {
+    override fun instantiateTarget() = KotlinOnlyTarget<KotlinCommonCompilation>(project, KotlinPlatformType.common)
+
     override fun getName(): String = PRESET_NAME
 
     override fun createCompilationFactory(