franta-hg@28: /**
franta-hg@28:  * parameter-lister
franta-hg@28:  * Copyright © 2015 František Kučera (frantovo.cz)
franta-hg@28:  *
franta-hg@28:  * This program is free software: you can redistribute it and/or modify
franta-hg@28:  * it under the terms of the GNU General Public License as published by
franta-hg@28:  * the Free Software Foundation, either version 3 of the License, or
franta-hg@28:  * (at your option) any later version.
franta-hg@28:  *
franta-hg@28:  * This program is distributed in the hope that it will be useful,
franta-hg@28:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
franta-hg@28:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
franta-hg@28:  * GNU General Public License for more details.
franta-hg@28:  *
franta-hg@28:  * You should have received a copy of the GNU General Public License
franta-hg@28:  * along with this program. If not, see <http://www.gnu.org/licenses/>.
franta-hg@28:  */
franta-hg@21: package info.glogalcode.parameterLister;
franta-hg@21: 
franta-hg@21: import info.glogalcode.parameterLister.modules.TerminalModuleFactory;
franta-hg@21: import java.util.Arrays;
franta-hg@21: import java.util.HashMap;
franta-hg@21: import java.util.Map;
franta-hg@21: import java.util.ServiceLoader;
franta-hg@21: import java.util.logging.Level;
franta-hg@21: import java.util.logging.Logger;
franta-hg@21: 
franta-hg@21: /**
franta-hg@21:  *
franta-hg@21:  * @author Ing. František Kučera (frantovo.cz)
franta-hg@21:  */
franta-hg@21: public class CLI {
franta-hg@21: 
franta-hg@21: 	public static final String ENV_BASE = "PARAMETER_LISTER";
franta-hg@21: 	public static final String ENV_OUTPUT_MODULE_NAME = ENV_BASE + "_OUTPUT";
franta-hg@21: 	public static final String DEFAULT_MODULE = TerminalModuleFactory.MODULE_NAME;
franta-hg@21: 
franta-hg@21: 	public static final int EXIT_SUCCESS = 0;
franta-hg@21: 	public static final int EXIT_UNEXPECTED_ERROR = 1;
franta-hg@21: 	// 2 is reserved: http://www.tldp.org/LDP/abs/html/exitcodes.html#EXITCODESREF
franta-hg@21: 	public static final int EXIT_MODULE_ERROR = 3;
franta-hg@21: 
franta-hg@21: 	private static final Logger log = Logger.getLogger(CLI.class.getName());
franta-hg@21: 
franta-hg@21: 	public static void main(String[] args) {
franta-hg@21: 
franta-hg@21: 		try {
franta-hg@21: 			ServiceLoader<OutputModuleFactory> modulesLoader = ServiceLoader.load(OutputModuleFactory.class);
franta-hg@21: 			final Map<String, OutputModuleFactory> modules = new HashMap<>();
franta-hg@21: 			modulesLoader.forEach(f -> modules.put(f.getName(), f));
franta-hg@21: 
franta-hg@21: 			String moduleName = System.getenv(ENV_OUTPUT_MODULE_NAME);
franta-hg@21: 			OutputModuleFactory moduleFactory = modules.getOrDefault(moduleName, modules.get(DEFAULT_MODULE));
franta-hg@21: 			OutputModule module = moduleFactory.createModule();
franta-hg@21: 
franta-hg@21: 			try {
franta-hg@21: 				module.process(System.out, Arrays.asList(args));
franta-hg@21: 			} catch (OutputModuleException e) {
franta-hg@21: 				log.log(Level.SEVERE, "Error while processing output with module " + module.getClass().getName(), e);
franta-hg@21: 				System.exit(EXIT_MODULE_ERROR);
franta-hg@21: 			}
franta-hg@21: 		} catch (Exception e) {
franta-hg@21: 			log.log(Level.SEVERE, "Unexpected exception, probably bug.", e);
franta-hg@21: 			System.exit(EXIT_UNEXPECTED_ERROR);
franta-hg@21: 
franta-hg@21: 		}
franta-hg@21: 		System.exit(EXIT_SUCCESS);
franta-hg@21: 	}
franta-hg@21: 
franta-hg@21: }