| /* |
| * 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.twill.launcher; |
| |
| import org.apache.twill.internal.Constants; |
| |
| import java.io.BufferedReader; |
| import java.io.File; |
| import java.io.IOException; |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.net.MalformedURLException; |
| import java.net.URL; |
| import java.net.URLClassLoader; |
| import java.nio.charset.StandardCharsets; |
| import java.nio.file.Files; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.Comparator; |
| import java.util.List; |
| import java.util.Map; |
| |
| /** |
| * A launcher for application from a archive jar. |
| * This class should have no dependencies on any library except the J2SE one. |
| * This class should not import any thing except java.* |
| */ |
| public final class TwillLauncher { |
| |
| /** |
| * Main method to unpackage a jar and run the mainClass.main() method. |
| * @param args args[0] is the class name of the mainClass, args[1] is a boolean, telling whether to append classpath |
| * from the "classpath.txt" runtime config jar or not. The rest of args are arguments to the mainClass. |
| */ |
| public static void main(String[] args) throws Exception { |
| if (args.length < 2) { |
| System.out.println("Usage: java " + TwillLauncher.class.getName() + " [mainClass] [use_classpath] [args...]"); |
| return; |
| } |
| |
| String mainClassName = args[0]; |
| boolean userClassPath = Boolean.parseBoolean(args[1]); |
| |
| // Create ClassLoader |
| URL[] classpath = createClasspath(userClassPath); |
| ClassLoader classLoader = createContainerClassLoader(classpath); |
| System.out.println("Launch class (" + mainClassName + ") using classloader " + classLoader.getClass().getName() |
| + " with classpath: " + Arrays.toString(classpath)); |
| |
| Thread.currentThread().setContextClassLoader(classLoader); |
| |
| Class<?> mainClass = classLoader.loadClass(mainClassName); |
| Method mainMethod = mainClass.getMethod("main", String[].class); |
| String[] arguments = Arrays.copyOfRange(args, 2, args.length); |
| System.out.println("Launching main: " + mainMethod + " " + Arrays.toString(arguments)); |
| mainMethod.invoke(mainClass, new Object[]{arguments}); |
| System.out.println("Main class completed."); |
| |
| System.out.println("Launcher completed"); |
| } |
| |
| private static URL[] createClasspath(boolean useClassPath) throws IOException { |
| List<URL> urls = new ArrayList<>(); |
| |
| File appJarDir = new File(Constants.Files.APPLICATION_JAR); |
| File resourceJarDir = new File(Constants.Files.RESOURCES_JAR); |
| File twillJarDir = new File(Constants.Files.TWILL_JAR); |
| |
| // For backward compatibility, sort jars from twill and jars from application together |
| // With TWILL-179, this will change as the user can have control on how it should be. |
| List<File> libJarFiles = listJarFiles(new File(appJarDir, "lib"), new ArrayList<>()); |
| listJarFiles(new File(twillJarDir, "lib"), libJarFiles).sort(Comparator.comparing(File::getName)); |
| |
| // Add the app jar, resources jar and twill jar directories to the classpath as well |
| for (File dir : Arrays.asList(appJarDir, twillJarDir)) { |
| urls.add(dir.toURI().toURL()); |
| urls.add(new File(dir, "classes").toURI().toURL()); |
| } |
| |
| // this indicates that we are not in the ApplicationMaster |
| if (useClassPath) { |
| urls.add(new File(resourceJarDir, "resources").toURI().toURL()); |
| } |
| |
| // Add all lib jars |
| for (File jarFile : libJarFiles) { |
| urls.add(jarFile.toURI().toURL()); |
| } |
| |
| if (useClassPath) { |
| addClassPathsToList(urls, new File(Constants.Files.RUNTIME_CONFIG_JAR, Constants.Files.CLASSPATH)); |
| } |
| |
| addClassPathsToList(urls, new File(Constants.Files.RUNTIME_CONFIG_JAR, Constants.Files.APPLICATION_CLASSPATH)); |
| return urls.toArray(new URL[0]); |
| } |
| |
| /** |
| * Creates a {@link ClassLoader} to be used by this container that load classes from the given classpath. |
| */ |
| private static ClassLoader createContainerClassLoader(URL[] classpath) { |
| String containerClassLoaderName = System.getProperty(Constants.TWILL_CONTAINER_CLASSLOADER); |
| URLClassLoader classLoader = new URLClassLoader(classpath); |
| if (containerClassLoaderName == null) { |
| return classLoader; |
| } |
| |
| try { |
| @SuppressWarnings("unchecked") |
| Class<? extends ClassLoader> cls = (Class<? extends ClassLoader>) classLoader.loadClass(containerClassLoaderName); |
| |
| // Instantiate with constructor (URL[] classpath, ClassLoader parentClassLoader) |
| return cls.getConstructor(URL[].class, ClassLoader.class).newInstance(classpath, classLoader.getParent()); |
| } catch (ClassNotFoundException e) { |
| throw new RuntimeException("Failed to load container class loader class " + containerClassLoaderName, e); |
| } catch (NoSuchMethodException e) { |
| throw new RuntimeException("Container class loader must have a public constructor with " + |
| "parameters (URL[] classpath, ClassLoader parent)", e); |
| } catch (InstantiationException | InvocationTargetException | IllegalAccessException e) { |
| throw new RuntimeException("Failed to create container class loader of class " + containerClassLoaderName, e); |
| } |
| } |
| |
| private static void addClassPathsToList(List<URL> urls, File classpathFile) throws IOException { |
| try (BufferedReader reader = Files.newBufferedReader(classpathFile.toPath(), StandardCharsets.UTF_8)) { |
| String line = reader.readLine(); |
| if (line != null) { |
| for (String path : expand(line).split(":")) { |
| urls.addAll(getClassPaths(path.trim())); |
| } |
| } |
| } |
| } |
| |
| private static Collection<URL> getClassPaths(String path) throws MalformedURLException { |
| String classpath = expand(path); |
| if (classpath.endsWith("/*")) { |
| // Grab all .jar files |
| File dir = new File(classpath.substring(0, classpath.length() - 2)); |
| List<File> files = listJarFiles(dir, new ArrayList<>()); |
| Collections.sort(files); |
| if (files.isEmpty()) { |
| return singleItem(dir.toURI().toURL()); |
| } |
| |
| List<URL> result = new ArrayList<>(files.size()); |
| for (File file : files) { |
| if (file.getName().endsWith(".jar")) { |
| result.add(file.toURI().toURL()); |
| } |
| } |
| return result; |
| } else { |
| return singleItem(new File(classpath).toURI().toURL()); |
| } |
| } |
| |
| private static Collection<URL> singleItem(URL url) { |
| List<URL> result = new ArrayList<>(1); |
| result.add(url); |
| return result; |
| } |
| |
| private static String expand(String value) { |
| String result = value; |
| for (Map.Entry<String, String> entry : System.getenv().entrySet()) { |
| result = result.replace("$" + entry.getKey(), entry.getValue()); |
| result = result.replace("${" + entry.getKey() + "}", entry.getValue()); |
| } |
| return result; |
| } |
| |
| /** |
| * Populates a list of {@link File} under the given directory that has ".jar" as extension. |
| */ |
| private static List<File> listJarFiles(File dir, List<File> result) { |
| File[] files = dir.listFiles(); |
| if (files == null || files.length == 0) { |
| return result; |
| } |
| for (File file : files) { |
| if (file.getName().endsWith(".jar")) { |
| result.add(file); |
| } |
| } |
| return result; |
| } |
| } |