Java tutorial
/* * 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.sling.testing.serversetup.jarexec; import java.io.File; import java.io.IOException; import java.util.Arrays; import java.util.Properties; import java.util.regex.Pattern; import org.apache.commons.exec.CommandLine; import org.apache.commons.exec.DefaultExecutor; import org.apache.commons.exec.ExecuteException; import org.apache.commons.exec.ExecuteResultHandler; import org.apache.commons.exec.Executor; import org.apache.commons.exec.PumpStreamHandler; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** Start a runnable jar by forking a JVM process, * and terminate the process when this VM exits. */ @SuppressWarnings("ALL") public class JarExecutor { private final File jarToExecute; private final String jvmFullPath; private final int serverPort; private final Properties config; private Executor executor; private final Logger log = LoggerFactory.getLogger(getClass()); public static final int DEFAULT_PORT = 8765; public static final int DEFAULT_EXIT_TIMEOUT = 30; public static final String DEFAULT_JAR_FOLDER = "target/dependency"; public static final String DEFAULT_JAR_NAME_REGEXP = "org.apache.sling.*jar$"; public static final String PROP_PREFIX = "jar.executor."; public static final String PROP_SERVER_PORT = PROP_PREFIX + "server.port"; public static final String PROP_JAR_FOLDER = PROP_PREFIX + "jar.folder"; public static final String PROP_JAR_NAME_REGEXP = PROP_PREFIX + "jar.name.regexp"; public static final String PROP_VM_OPTIONS = PROP_PREFIX + "vm.options"; public static final String PROP_WORK_FOLDER = PROP_PREFIX + "work.folder"; public static final String PROP_JAR_OPTIONS = PROP_PREFIX + "jar.options"; public static final String PROP_EXIT_TIMEOUT_SECONDS = PROP_PREFIX + "exit.timeout.seconds"; public static final String PROP_WAIT_ONSHUTDOWN = PROP_PREFIX + "wait.on.shutdown"; public static final String PROP_JAVA_PATH = PROP_PREFIX + "java.executable.path"; public static final String PROP_SYNC_EXEC = PROP_PREFIX + "synchronous.exec"; public static final String PROP_SYNC_EXEC_EXPECTED = PROP_PREFIX + "synchronous.exec.expected.result"; @SuppressWarnings("serial") public static class ExecutorException extends Exception { ExecutorException(String reason) { super(reason); } ExecutorException(String reason, Throwable cause) { super(reason, cause); } } @Override public String toString() { return getClass().getSimpleName() + ": " + jarToExecute.getName() + " (port " + serverPort + ")"; } public int getServerPort() { return serverPort; } /** Build a JarExecutor, locate the jar to run, etc */ public JarExecutor(Properties config) throws ExecutorException { this.config = config; final boolean isWindows = System.getProperty("os.name").toLowerCase().contains("windows"); String portStr = config.getProperty(PROP_SERVER_PORT); serverPort = portStr == null ? DEFAULT_PORT : Integer.valueOf(portStr); final String configJvmPath = config.getProperty(PROP_JAVA_PATH); if (configJvmPath == null) { final String javaExecutable = isWindows ? "java.exe" : "java"; jvmFullPath = System.getProperty("java.home") + File.separator + "bin" + File.separator + javaExecutable; } else { jvmFullPath = configJvmPath; } String jarFolderPath = config.getProperty(PROP_JAR_FOLDER); jarFolderPath = jarFolderPath == null ? DEFAULT_JAR_FOLDER : jarFolderPath; final File jarFolder = new File(jarFolderPath); String jarNameRegexp = config.getProperty(PROP_JAR_NAME_REGEXP); jarNameRegexp = jarNameRegexp == null ? DEFAULT_JAR_NAME_REGEXP : jarNameRegexp; final Pattern jarPattern = Pattern.compile(jarNameRegexp); // Find executable jar final String[] candidates = jarFolder.list(); if (candidates == null) { throw new ExecutorException("No files found in jar folder specified by " + PROP_JAR_FOLDER + " property: " + jarFolder.getAbsolutePath()); } File f = null; for (String filename : candidates) { if (jarPattern.matcher(filename).matches()) { f = new File(jarFolder, filename); break; } } if (f == null) { throw new ExecutorException("Executable jar matching '" + jarPattern + "' not found in " + jarFolder.getAbsolutePath() + ", candidates are " + Arrays.asList(candidates)); } jarToExecute = f; } /** Start the jar if not done yet, and setup runtime hook * to stop it. */ public void start() throws Exception { final ExecuteResultHandler h = new ExecuteResultHandler() { public void onProcessFailed(ExecuteException ex) { log.error("Process execution failed:" + ex, ex); } public void onProcessComplete(int result) { log.info("Process execution complete, exit code=" + result); } }; final String vmOptions = config.getProperty(PROP_VM_OPTIONS); executor = new DefaultExecutor(); final CommandLine cl = new CommandLine(jvmFullPath); if (vmOptions != null && vmOptions.length() > 0) { cl.addArguments(vmOptions); } cl.addArgument("-jar"); cl.addArgument(jarToExecute.getAbsolutePath()); // Additional options for the jar that's executed. // $JAREXEC_SERVER_PORT$ is replaced our serverPort value String jarOptions = config.getProperty(PROP_JAR_OPTIONS); if (jarOptions != null && jarOptions.length() > 0) { jarOptions = jarOptions.replaceAll("\\$JAREXEC_SERVER_PORT\\$", String.valueOf(serverPort)); log.info("Executable jar options: {}", jarOptions); cl.addArguments(jarOptions); } final String workFolderOption = config.getProperty(PROP_WORK_FOLDER); if (workFolderOption != null && workFolderOption.length() > 0) { final File workFolder = new File(workFolderOption); if (!workFolder.isDirectory()) { throw new IOException("Work dir set by " + PROP_WORK_FOLDER + " option does not exist: " + workFolder.getAbsolutePath()); } log.info("Setting working directory for executable jar: {}", workFolder.getAbsolutePath()); executor.setWorkingDirectory(workFolder); } String tmStr = config.getProperty(PROP_EXIT_TIMEOUT_SECONDS); final int exitTimeoutSeconds = tmStr == null ? DEFAULT_EXIT_TIMEOUT : Integer.valueOf(tmStr); if ("true".equals(config.getProperty(PROP_SYNC_EXEC, ""))) { final long start = System.currentTimeMillis(); log.info("Executing and waiting for result: " + cl); final int result = executor.execute(cl); final int expected = Integer.valueOf(config.getProperty(PROP_SYNC_EXEC_EXPECTED, "0")); log.info("Execution took " + (System.currentTimeMillis() - start) + " msec"); if (result != expected) { throw new ExecutorException("Expected result code " + expected + ", got " + result); } } else { log.info("Executing asynchronously: " + cl); executor.setStreamHandler(new PumpStreamHandler()); final ShutdownHookSingleProcessDestroyer pd = new ShutdownHookSingleProcessDestroyer( "java -jar " + jarToExecute.getName(), exitTimeoutSeconds); final boolean waitOnShutdown = Boolean.valueOf(config.getProperty(PROP_WAIT_ONSHUTDOWN, "false")); log.info("Setting up ProcessDestroyer with waitOnShutdown=" + waitOnShutdown); pd.setWaitOnShutdown(waitOnShutdown); executor.setProcessDestroyer(pd); executor.execute(cl, h); } } /** Stop the process that we started, if any, and wait for it to exit before returning */ public void stop() { if (executor == null) { throw new IllegalStateException("Process not started, no Executor set"); } final Object d = executor.getProcessDestroyer(); if (d instanceof ShutdownHookSingleProcessDestroyer) { ((ShutdownHookSingleProcessDestroyer) d).destroyProcess(true); log.info("Process destroyed"); } else { throw new IllegalStateException(d + " is not a Runnable, cannot destroy process"); } } }