lucene/gradle/java/core-mrjar.gradle

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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
 *
 *     http://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.
 */

// Produce an MR-JAR with Java 19+ foreign and vector implementations

configure(project(":lucene:core")) {
  plugins.withType(JavaPlugin) {
    mrjarJavaVersions.each { jdkVersion ->
      sourceSets.create("main${jdkVersion}") {
        java {
          srcDirs = ["src/java${jdkVersion}"]
        }
      }
      configurations["main${jdkVersion}Implementation"].extendsFrom(configurations['implementation'])
      dependencies.add("main${jdkVersion}Implementation", sourceSets.main.output)

      tasks.named("compileMain${jdkVersion}Java").configure {
        def apijar = apijars.file("jdk${jdkVersion}.apijar")
        
        int releaseIndex = options.compilerArgs.indexOf("--release")
        options.compilerArgs.removeAt(releaseIndex)
        options.compilerArgs.removeAt(releaseIndex)
        options.compilerArgs += [
          "-Xlint:-options",
          "--add-exports", "java.base/java.lang.foreign=ALL-UNNAMED",
          // for compilation we patch the incubator packages into java.base, this has no effect on resulting class files:
          "--add-exports", "java.base/jdk.incubator.vector=ALL-UNNAMED",
        ]

        options.compilerArgumentProviders.add(new CompilerArgsProvider(apiJarFile: apijar))
      }
    }
    
    tasks.named('jar').configure {
      boolean needMRJAR = false;
      mrjarJavaVersions.each { jdkVersion ->
        // the sourceSet which corresponds to the minimum/base Java version
        // will copy its output to root of JAR, all other sourceSets will go into MR-JAR folders:
        boolean isBaseVersion = (jdkVersion.toString() == rootProject.minJavaVersion.toString())
        into(isBaseVersion ? '' : "META-INF/versions/${jdkVersion}") {
          from sourceSets["main${jdkVersion}"].output
        }
        needMRJAR |= !isBaseVersion
      }

      if (needMRJAR) {
        manifest.attributes(
          'Multi-Release': 'true'
        )
      }
    }
  }
}

class CompilerArgsProvider implements CommandLineArgumentProvider {

  @InputFile
  @PathSensitive(PathSensitivity.RELATIVE)
  RegularFile apiJarFile

  @Override
  Iterable<String> asArguments() {
    return ["--patch-module", "java.base=${apiJarFile}"]
  }
}