Java tutorial
/** * ========================================================================================== * = JAHIA'S DUAL LICENSING - IMPORTANT INFORMATION = * ========================================================================================== * * http://www.jahia.com * * Copyright (C) 2002-2017 Jahia Solutions Group SA. All rights reserved. * * THIS FILE IS AVAILABLE UNDER TWO DIFFERENT LICENSES: * 1/GPL OR 2/JSEL * * 1/ GPL * ================================================================================== * * IF YOU DECIDE TO CHOOSE THE GPL LICENSE, YOU MUST COMPLY WITH THE FOLLOWING TERMS: * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. * * * 2/ JSEL - Commercial and Supported Versions of the program * =================================================================================== * * IF YOU DECIDE TO CHOOSE THE JSEL LICENSE, YOU MUST COMPLY WITH THE FOLLOWING TERMS: * * Alternatively, commercial and supported versions of the program - also known as * Enterprise Distributions - must be used in accordance with the terms and conditions * contained in a separate written agreement between you and Jahia Solutions Group SA. * * If you are unsure which license is appropriate for your use, * please contact the sales department at sales@jahia.com. */ package org.jahia.utils; import org.apache.commons.exec.CommandLine; import org.apache.commons.exec.DefaultExecutor; import org.apache.commons.exec.ExecuteException; import org.apache.commons.exec.PumpStreamHandler; import org.jahia.exceptions.JahiaRuntimeException; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import java.io.File; import java.util.Map; /** * Utility class for executing external processes. * * @author Sergiy Shyrkov */ public final class ProcessHelper { private static final Logger logger = LoggerFactory.getLogger(ProcessHelper.class); /** * Executes the external process using the provided command. * * @param command * the command to be executed * @return the execution status * @throws JahiaRuntimeException * in case the process execution failed */ public static int execute(String command) throws JahiaRuntimeException { return execute(command, null); } /** * Executes the external process using the provided command, arguments (optional). * * @param command * the command to be executed * @param arguments * optional arguments for the command * @return the execution status * @throws JahiaRuntimeException * in case the process execution failed */ public static int execute(String command, String[] arguments) throws JahiaRuntimeException { return execute(command, arguments, null); } /** * Executes the external process using the provided command, arguments (optional), parameter substitution map to expand variables in the * command or arguments in form of <code>${variable}<code> (optional). * * @param command * the command to be executed * @param arguments * optional arguments for the command * @param parameterSubstitutionMap * optional values for variables to be expanded * @return the execution status * @throws JahiaRuntimeException * in case the process execution failed */ public static int execute(String command, String[] arguments, Map<String, Object> parameterSubstitutionMap) throws JahiaRuntimeException { return execute(command, arguments, parameterSubstitutionMap, null, null, null); } /** * Executes the external process using the provided command, arguments (optional), parameter substitution map to expand variables in the * command or arguments in form of <code>${variable}<code> (optional) and a working directory (optional). * Buffers for process output and error stream can be provided. * * @param command * the command to be executed * @param arguments * optional arguments for the command * @param parameterSubstitutionMap * optional values for variables to be expanded * @param workingDir * optional working directory for the process to be started from * @param resultOut * the buffer to write the process execution output into (optional) * @param resultErr * the buffer to write the process execution error into (optional) * @return the execution status * @throws JahiaRuntimeException * in case the process execution failed */ public static int execute(String command, String arguments[], Map<String, Object> parameterSubstitutionMap, File workingDir, StringBuilder resultOut, StringBuilder resultErr) throws JahiaRuntimeException { return execute(command, arguments, parameterSubstitutionMap, workingDir, resultOut, resultErr, true); } /** * Executes the external process using the provided command, arguments (optional), parameter substitution map to expand variables in the * command or arguments in form of <code>${variable}<code> (optional) and a working directory (optional). * Buffers for process output and error stream can be provided. * * @param command * the command to be executed * @param arguments * optional arguments for the command * @param parameterSubstitutionMap * optional values for variables to be expanded * @param workingDir * optional working directory for the process to be started from * @param resultOut * the buffer to write the process execution output into (optional) * @param resultErr * the buffer to write the process execution error into (optional) * @return the execution status * @return redirectOutputs if set to <code>true</code> the output of the execution will be also redirected to standard system out and * the error to error out * @throws JahiaRuntimeException * in case the process execution failed */ public static int execute(String command, String arguments[], Map<String, Object> parameterSubstitutionMap, File workingDir, StringBuilder resultOut, StringBuilder resultErr, boolean redirectOutputs) throws JahiaRuntimeException { long timer = System.currentTimeMillis(); CommandLine cmd = new CommandLine(command); if (arguments != null && arguments.length > 0) { cmd.addArguments(arguments, false); } if (parameterSubstitutionMap != null && !parameterSubstitutionMap.isEmpty()) { cmd.setSubstitutionMap(parameterSubstitutionMap); } if (logger.isDebugEnabled()) { logger.debug("Executing command: {}", cmd.toString()); } else if (redirectOutputs) { logger.info("Executing command: "); logger.info(cmd.toString()); } int exitValue = 0; StringOutputStream out = new StringOutputStream(redirectOutputs ? System.out : null); StringOutputStream err = new StringOutputStream(redirectOutputs ? System.err : null); try { DefaultExecutor executor = new DefaultExecutor(); executor.setStreamHandler(new PumpStreamHandler(out, err)); if (workingDir != null) { if (workingDir.exists() || workingDir.mkdirs()) { executor.setWorkingDirectory(workingDir); } } exitValue = executor.execute(cmd, System.getenv()); } catch (ExecuteException ee) { return ee.getExitValue(); } catch (Exception e) { throw new JahiaRuntimeException(e); } finally { if (resultErr != null) { resultErr.append(err.toString()); } if (resultOut != null) { resultOut.append(out.toString()); } if (exitValue > 0) { logger.error("External process finished with error. Cause: {}", err.toString()); } if (logger.isDebugEnabled()) { logger.debug("Execution took {} ms and finished with status {} and output {}", new Object[] { (System.currentTimeMillis() - timer), exitValue, out.toString() }); } } return exitValue; } }