package org.codehaus.plexus.languages.java.jpms;
   
   /*
    * 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.
   */
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.nio.file.Files;
  import java.nio.file.Path;
  import java.util.jar.JarEntry;
  import java.util.jar.JarFile;
  import java.util.jar.Manifest;
  
  import org.codehaus.plexus.languages.java.version.JavaVersion;
  
  abstract class AbstractBinaryModuleInfoParser implements ModuleInfoParser {
      @Override
      public JavaModuleDescriptor getModuleDescriptor(Path modulePath) throws IOException {
          return getModuleDescriptor(modulePath, JavaVersion.JAVA_SPECIFICATION_VERSION);
      }
  
      @Override
      public JavaModuleDescriptor getModuleDescriptor(Path modulePath, JavaVersion jdkVersion) throws IOException {
          JavaModuleDescriptor descriptor;
          if (Files.isDirectory(modulePath)) {
              try (InputStream in = Files.newInputStream(modulePath.resolve("module-info.class"))) {
                  descriptor = parse(in);
              }
          } else {
              try (JarFile jarFile = new JarFile(modulePath.toFile())) {
                  JarEntry moduleInfo;
                  if (modulePath.toString().toLowerCase().endsWith(".jmod")) {
                      moduleInfo = jarFile.getJarEntry("classes/module-info.class");
                  } else {
                      moduleInfo = jarFile.getJarEntry("module-info.class");
  
                      if (moduleInfo == null) {
                          Manifest manifest = jarFile.getManifest();
  
                          if (manifest != null
                                  && "true"
                                          .equalsIgnoreCase(
                                                  manifest.getMainAttributes().getValue("Multi-Release"))) {
                              int javaVersion =
                                      Integer.parseInt(jdkVersion.asMajor().getValue(1));
  
                              for (int version = javaVersion; version >= 9; version--) {
                                  String resource = "META-INF/versions/" + version + "/module-info.class";
                                  JarEntry entry = jarFile.getJarEntry(resource);
                                  if (entry != null) {
                                      moduleInfo = entry;
                                      break;
                                  }
                              }
                          }
                      }
                  }
  
                  if (moduleInfo != null) {
                      descriptor = parse(jarFile.getInputStream(moduleInfo));
                  } else {
                      descriptor = null;
                  }
              }
          }
          return descriptor;
      }
  
      abstract JavaModuleDescriptor parse(InputStream in) throws IOException;
  }