Kotlinify PlugPlugin.

Author: nedtwigg

atplug-plugin-gradle/src/main/java/com/diffplug/atplug/tooling/gradle/PlugPlugin.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright (C) 2020-2023 DiffPlug
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.diffplug.atplug.tooling.gradle
+
+import java.io.File
+import java.io.Serializable
+import org.gradle.api.Action
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+import org.gradle.api.Task
+import org.gradle.api.UnknownTaskException
+import org.gradle.api.artifacts.Configuration
+import org.gradle.api.plugins.JavaPlugin
+import org.gradle.api.plugins.JavaPluginExtension
+import org.gradle.api.tasks.SourceSet
+import org.gradle.jvm.tasks.Jar
+
+/**
+ * `plugGenerate` task uses `@Plug` to generate files in `src/main/resources/ATPLUG-INF` as a
+ * dependency of `processResources`.
+ */
+class PlugPlugin : Plugin<Project> {
+	override fun apply(project: Project) {
+		// get the classes we're compiling
+		project.plugins.apply(JavaPlugin::class.java)
+		val javaExtension = project.extensions.getByType(JavaPluginExtension::class.java)
+		val main = javaExtension.sourceSets.getByName(SourceSet.MAIN_SOURCE_SET_NAME)
+		val dep = project.dependencies.create("org.jetbrains.kotlin:kotlin-reflect:1.8.20")
+		val plugGenConfig =
+				project.configurations.create("plugGenerate") { plugGen: Configuration ->
+					plugGen.extendsFrom(
+							project.configurations.getByName(JavaPlugin.RUNTIME_CLASSPATH_CONFIGURATION_NAME))
+					plugGen.dependencies.add(dep)
+				}
+
+		// jar --dependsOn--> plugGenerate
+		val generateTask =
+				project.tasks.register<PlugGenerateTask>(GENERATE, PlugGenerateTask::class.java) {
+						task: PlugGenerateTask ->
+					task.setClassesFolders(main.output.classesDirs)
+					task.jarsToLinkAgainst.setFrom(plugGenConfig)
+					task.resourcesFolder = main.resources.sourceDirectories.singleFile
+					// dep on java
+					for (taskName in mutableListOf("compileJava", "compileKotlin")) {
+						try {
+							task.dependsOn(project.tasks.named(taskName))
+						} catch (e: UnknownTaskException) {
+							// not a problem
+						}
+					}
+				}
+		project.tasks.named(JavaPlugin.JAR_TASK_NAME).configure { jarTaskUntyped: Task ->
+			val jarTask = jarTaskUntyped as Jar
+			val metadataTask = generateTask.get()
+			jarTask.inputs.dir(metadataTask.atplugInfFolder)
+			jarTask.doFirst(
+					"Set " + SERVICE_COMPONENT + " header",
+					SetServiceComponentHeader(metadataTask.atplugInfFolder))
+		}
+		project.tasks.named(JavaPlugin.PROCESS_RESOURCES_TASK_NAME).configure { t: Task ->
+			t.dependsOn(generateTask)
+		}
+	}
+
+	internal class SetServiceComponentHeader(private val atplugInfFolder: File) :
+			Serializable, Action<Task> {
+		override fun execute(task: Task) {
+			val serviceComponents = PlugGenerateTask.atplugComponents(atplugInfFolder)
+			val jarTask = task as Jar
+			if (serviceComponents == null) {
+				jarTask.manifest.attributes.remove(SERVICE_COMPONENT)
+			} else {
+				jarTask.manifest.attributes[SERVICE_COMPONENT] = serviceComponents
+			}
+		}
+	}
+
+	companion object {
+		const val GENERATE = "plugGenerate"
+		const val SERVICE_COMPONENT = "AtPlug-Component"
+		const val DOT_JSON = ".json"
+		const val ATPLUG_INF = "ATPLUG-INF/"
+	}
+}