| /* |
| * 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. |
| */ |
| |
| package org.apache.lucene.luke.util.reflection; |
| |
| import java.io.IOException; |
| import java.lang.invoke.MethodHandles; |
| import java.net.URL; |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.Enumeration; |
| import java.util.HashSet; |
| import java.util.List; |
| import java.util.Set; |
| import java.util.concurrent.ExecutorService; |
| import java.util.concurrent.Executors; |
| import java.util.concurrent.TimeUnit; |
| |
| import org.apache.logging.log4j.Logger; |
| import org.apache.lucene.luke.util.LoggerFactory; |
| import org.apache.lucene.util.NamedThreadFactory; |
| |
| /** |
| * Utility class for scanning class files in jars. |
| */ |
| public class ClassScanner { |
| |
| private static final Logger log = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass()); |
| |
| private final String packageName; |
| private final ClassLoader[] classLoaders; |
| |
| public ClassScanner(String packageName, ClassLoader... classLoaders) { |
| this.packageName = packageName; |
| this.classLoaders = classLoaders; |
| } |
| |
| public <T> Set<Class<? extends T>> scanSubTypes(Class<T> superType) { |
| final int numThreads = Runtime.getRuntime().availableProcessors(); |
| |
| List<SubtypeCollector<T>> collectors = new ArrayList<>(); |
| for (int i = 0; i < numThreads; i++) { |
| collectors.add(new SubtypeCollector<T>(superType, packageName, classLoaders)); |
| } |
| |
| try { |
| List<URL> urls = getJarUrls(); |
| for (int i = 0; i < urls.size(); i++) { |
| collectors.get(i % numThreads).addUrl(urls.get(i)); |
| } |
| |
| ExecutorService executorService = Executors.newFixedThreadPool(numThreads, new NamedThreadFactory("scanner-scan-subtypes")); |
| for (SubtypeCollector<T> collector : collectors) { |
| executorService.submit(collector); |
| } |
| |
| try { |
| executorService.shutdown(); |
| executorService.awaitTermination(10, TimeUnit.SECONDS); |
| } catch (InterruptedException e) { |
| } finally { |
| executorService.shutdownNow(); |
| } |
| |
| Set<Class<? extends T>> types = new HashSet<>(); |
| for (SubtypeCollector<T> collector : collectors) { |
| types.addAll(collector.getTypes()); |
| } |
| return types; |
| } catch (IOException e) { |
| log.error("Cannot load jar file entries", e); |
| } |
| return Collections.emptySet(); |
| } |
| |
| private List<URL> getJarUrls() throws IOException { |
| List<URL> urls = new ArrayList<>(); |
| String resourceName = resourceName(packageName); |
| for (ClassLoader loader : classLoaders) { |
| for (Enumeration<URL> e = loader.getResources(resourceName); e.hasMoreElements(); ) { |
| URL url = e.nextElement(); |
| // extract jar file path from the resource name |
| int index = url.getPath().lastIndexOf(".jar"); |
| if (index > 0) { |
| String path = url.getPath().substring(0, index + 4); |
| urls.add(new URL(path)); |
| } |
| } |
| } |
| return urls; |
| } |
| |
| private static String resourceName(String packageName) { |
| if (packageName == null || packageName.equals("")) { |
| return packageName; |
| } |
| return packageName.replace('.', '/'); |
| } |
| } |