1.27.0: Add javaLauncher and toolchainSpec to `DownloadJbrForPlat…

…form` task

CHANGELOG.md

@@ -2,6 +2,14 @@
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## 1.27.0
+
+### Added
+
+- `DownloadJbrForPlatform#toolchainSpec`: a `Provider<JavaToolchainSpec>` that can be used with `JavaToolchainService`
+  to look up tools such as the Java launcher, compiler or Javadoc generator.
+- `DownloadJbrForPlatform#javaLauncher`: a `Provider<JavaLauncher>` that can be used with `JavaExec` tasks.
+
 ## 1.26.0
 
 ### Changed

api/mps-gradle-plugin.api

@@ -209,9 +209,11 @@ public class de/itemis/mps/gradle/downloadJBR/DownloadJbrConfiguration {
 }
 
 public class de/itemis/mps/gradle/downloadJBR/DownloadJbrForPlatform : org/gradle/api/DefaultTask {
-	public fun <init> ()V
+	public fun <init> (Lorg/gradle/api/model/ObjectFactory;Lorg/gradle/jvm/toolchain/JavaToolchainService;)V
 	public final fun getJavaExecutable ()Ljava/io/File;
+	public final fun getJavaLauncher ()Lorg/gradle/api/provider/Provider;
 	public final fun getJbrDir ()Ljava/io/File;
+	public final fun getToolchainSpec ()Lorg/gradle/api/provider/Provider;
 	public final fun setJavaExecutable (Ljava/io/File;)V
 	public final fun setJbrDir (Ljava/io/File;)V
 }

build.gradle.kts

@@ -24,7 +24,7 @@ plugins {
     id("org.jetbrains.kotlinx.binary-compatibility-validator") version "0.13.2"
 }
 
-val baseVersion = "1.26.0"
+val baseVersion = "1.27.0"
 
 group = "de.itemis.mps"
 

docs/plugins/download-jbr.md

@@ -1,17 +1,17 @@
 ## Download JetBrains Runtime
 
-When building MPS projects with the JetBrains Runtime, the JDK/JRE used by MPS and other intellij based IDEs, it's
-required to download the correct version of the runtime. Since the runtime is platform dependent it's required to
-download a platform dependent binary. While it's possible to add the logic to your own build script we provide a convenient
-way of doing this with a Gradle plugin.
+When building MPS projects with the JetBrains Runtime, the JDK/JRE used by MPS and other JetBrains IDEs, it's
+required to download the correct version of the runtime. Since the runtime is platform-dependent it is required to
+download a platform-dependent binary. While it's possible to add the logic to your own build script, we provide
+a convenient way of doing this with a Gradle plugin.
 
-The download-jbr plugin will add new dependencies and a task to your build. It will add a dependency to `com.jetbrains.jdk:jbr`
-to your build, you need to make sure that it is available in your dependency repositories. The itemis Maven repository at
-https://artifacts.itemis.cloud/repository/maven-mps provides this dependency, but you can create your own with
-the scripts located in [mbeddr/build.publish.jdk](https://github.com/mbeddr/build.publish.jdk).
+The `download-jbr` plugin will add new dependencies and a task to your build. It will add a dependency to
+`com.jetbrains.jdk:jbr` to your build, you need to make sure that it is available in your dependency repositories. The
+[itemis Maven repository](https://artifacts.itemis.cloud/repository/maven-mps) provides this dependency, but you can
+create your own with the scripts located in [mbeddr/build.publish.jdk](https://github.com/mbeddr/build.publish.jdk).
 
 For easy consumption and incremental build support the plugin creates a task `downloadJbr` which exposes the location of
-the java executable via the `javaExecutable` property. See
+the java executable via the `javaExecutable` and `javaLauncher` properties. See
 [the tests](../../src/test/kotlin/test/others/JBRDownloadTest.kt) for an example of how to use it.
 
 ### Usage
@@ -25,9 +25,7 @@ plugins {
 
 repositories {
     mavenCentral()
-    maven {
-        url = URI("https://artifacts.itemis.cloud/repository/maven-mps")
-    }
+    maven("https://artifacts.itemis.cloud/repository/maven-mps")
 }
 
 downloadJbr {
@@ -51,6 +49,7 @@ downloadJbr {
 ```
 
 ### Parameters
+
 * `jbrVersion` - version of the JBR to download. While this supports maven version selectors we highly recommend not
   using wildcards like `*` or `+` in there for reproducible builds.
 * `distributionType` - optional distribution type for the JBR to use. Will default to `jbr_jcef` if omitted.

src/main/kotlin/de/itemis/mps/gradle/downloadJBR/Tasks.kt

@@ -3,13 +3,23 @@ package de.itemis.mps.gradle.downloadJBR
 import org.gradle.api.DefaultTask
 import org.gradle.api.file.DirectoryProperty
 import org.gradle.api.file.RegularFileProperty
+import org.gradle.api.model.ObjectFactory
+import org.gradle.api.provider.Provider
 import org.gradle.api.tasks.*
+import org.gradle.jvm.toolchain.JavaLauncher
+import org.gradle.jvm.toolchain.JavaToolchainService
+import org.gradle.jvm.toolchain.JavaToolchainSpec
+import org.gradle.jvm.toolchain.internal.SpecificInstallationToolchainSpec
 import java.io.File
+import javax.inject.Inject
 
-open class DownloadJbrForPlatform : DefaultTask() {
+open class DownloadJbrForPlatform @Inject constructor(
+    private val objects: ObjectFactory,
+    private val javaToolchainService: JavaToolchainService
+) : DefaultTask() {
 
     @get:Internal
-    internal val jbrDirProperty: DirectoryProperty = project.objects.directoryProperty()
+    internal val jbrDirProperty: DirectoryProperty = objects.directoryProperty()
 
     @get:Internal
     var jbrDir : File
@@ -19,12 +29,26 @@ open class DownloadJbrForPlatform : DefaultTask() {
         }
 
     @get:Internal
-    internal val javaExecutableProperty: RegularFileProperty = project.objects.fileProperty()
+    internal val javaExecutableProperty: RegularFileProperty = objects.fileProperty()
 
     @get:Internal
     var javaExecutable: File
         get() = javaExecutableProperty.get().asFile
         set(value) {
             javaExecutableProperty.set(value)
         }
+
+    /**
+     * A [JavaToolchainSpec] that can be passed to [JavaToolchainService] to obtain various tools (Java compiler,
+     * launcher, javadoc).
+     */
+    @get:Internal
+    val toolchainSpec: Provider<JavaToolchainSpec> =
+        javaExecutableProperty.map { SpecificInstallationToolchainSpec.fromJavaExecutable(objects, it.asFile.path) }
+
+    /**
+     * A [JavaLauncher] for the downloaded JBR that can be used with [JavaExec] task.
+     */
+    @get:Internal
+    val javaLauncher: Provider<JavaLauncher> = toolchainSpec.flatMap(javaToolchainService::launcherFor)
 }

src/test/kotlin/test/others/JBRDownloadTest.kt

@@ -2,6 +2,8 @@ package test.others
 
 import org.gradle.testkit.runner.GradleRunner
 import org.gradle.testkit.runner.TaskOutcome
+import org.hamcrest.CoreMatchers.containsString
+import org.hamcrest.MatcherAssert.assertThat
 import org.junit.Assert
 import org.junit.Before
 import org.junit.Rule
@@ -199,4 +201,50 @@ class JBRDownloadTest {
                 .build()
         Assert.assertEquals(TaskOutcome.SUCCESS, result.task(":exec")?.outcome)
     }
+
+    @Test
+    fun `executed downloaded java using JavaLauncher`() {
+        settingsFile.writeText("""
+            rootProject.name = "hello-world"
+        """.trimIndent())
+
+        buildFile.writeText("""
+            import java.net.URI
+            import de.itemis.mps.gradle.downloadJBR.DownloadJbrForPlatform
+            
+            plugins {
+                id("download-jbr")
+            }
+            
+            repositories {
+                mavenCentral()
+                maven {
+                    url = URI("https://artifacts.itemis.cloud/repository/maven-mps")
+                }
+            }
+            
+            downloadJbr {
+                jbrVersion = "$JBR_VERSION"
+            }
+            
+            val downloadJbrTask = tasks.named("downloadJbr", DownloadJbrForPlatform::class)
+            
+            tasks.register<JavaExec>("exec") {
+                dependsOn(downloadJbrTask)
+                javaLauncher.set(downloadJbrTask.flatMap { it.javaLauncher })
+                jvmArgs("--version")
+
+                // Main class will be ignored due to --version but has to be provided
+                mainClass.set("ignored")
+            }
+        """.trimIndent())
+
+        val result = GradleRunner.create()
+            .withProjectDir(testProjectDir.root)
+            .withArguments("exec")
+            .withPluginClasspath()
+            .build()
+        Assert.assertEquals(TaskOutcome.SUCCESS, result.task(":exec")?.outcome)
+        assertThat(result.output, containsString("OpenJDK Runtime Environment JBR"))
+    }
 }