Java tutorial
/* * ======================================================================== * * Copyright 2005 Tim O'Brien. * * Licensed 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 com.discursive.jccook.cmdline; import org.apache.commons.cli.BasicParser; import org.apache.commons.cli.CommandLine; import org.apache.commons.cli.CommandLineParser; import org.apache.commons.cli.HelpFormatter; import org.apache.commons.cli.OptionBuilder; import org.apache.commons.cli.OptionGroup; import org.apache.commons.cli.Options; public class SomeApp { private static final String USAGE = "[-h] [-v] [-f <file> | -m <email>]"; private static final String HEADER = "SomeApp - A fancy and expensive program, Copyright 2010 Blah."; private static final String FOOTER = "For more instructions, see our website at: http://www.blah123.org"; public static void main(String[] args) throws Exception { // Create a Parser CommandLineParser parser = new BasicParser(); Options options = new Options(); options.addOption("h", "help", false, "Print this usage information"); options.addOption("v", "verbose", false, "Print out VERBOSE information"); OptionGroup optionGroup = new OptionGroup(); optionGroup.addOption(OptionBuilder.hasArg(true).withArgName("file").withLongOpt("file").create('f')); optionGroup.addOption(OptionBuilder.hasArg(true).withArgName("email").withLongOpt("email").create('m')); options.addOptionGroup(optionGroup); // Parse the program arguments try { CommandLine commandLine = parser.parse(options, args); if (commandLine.hasOption('h')) { printUsage(options); System.exit(0); } // ... do important stuff ... } catch (Exception e) { System.out.println("You provided bad program arguments!"); printUsage(options); System.exit(1); } } private static void printUsage(Options options) { HelpFormatter helpFormatter = new HelpFormatter(); helpFormatter.setWidth(80); helpFormatter.printHelp(USAGE, HEADER, options, FOOTER); } }