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.openejb.cli; import org.apache.commons.cli.CommandLine; import org.apache.commons.cli.CommandLineParser; import org.apache.commons.cli.HelpFormatter; import org.apache.commons.cli.Options; import org.apache.commons.cli.ParseException; import org.apache.commons.cli.PosixParser; import org.apache.openejb.loader.SystemInstance; import org.apache.openejb.util.OpenEjbVersion; import org.apache.openejb.util.OptionsLog; import org.apache.xbean.finder.ResourceFinder; import java.io.IOException; import java.io.PrintWriter; import java.io.StringWriter; import java.lang.reflect.Method; import java.net.URL; import java.util.ArrayList; import java.util.Enumeration; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.Properties; /** * Entry point for ALL things OpenEJB. This will use the new service * architecture explained here: * * @version $Rev$ $Date$ * @link http://docs.codehaus.org/display/OPENEJB/Executables */ public class MainImpl implements Main { private static final String BASE_PATH = "META-INF/org.apache.openejb.cli/"; private static final String MAIN_CLASS_PROPERTY_NAME = "main.class"; private static ResourceFinder finder; private static String locale = ""; private static final String descriptionBase = "description"; private static String descriptionI18n; public void main(String[] args) { args = processSystemProperties(args); finder = new ResourceFinder(BASE_PATH); locale = Locale.getDefault().getLanguage(); descriptionI18n = descriptionBase + "." + locale; final CommandLineParser parser = new PosixParser(); // create the Options final Options options = new Options(); options.addOption(null, "version", false, ""); options.addOption("h", "help", false, ""); options.addOption("e", "errors", false, "Produce execution error messages"); CommandLine line = null; String commandName = null; try { // parse the arguments up until the first // command, then let the rest fall into // the arguments array. line = parser.parse(options, args, true); // Get and remove the commandName (first arg) final List<String> list = line.getArgList(); if (list.size() > 0) { commandName = list.get(0); list.remove(0); } // The rest of the args will be passed to the command args = line.getArgs(); } catch (final ParseException exp) { exp.printStackTrace(); System.exit(-1); } if (line.hasOption("version")) { OpenEjbVersion.get().print(System.out); System.exit(0); } else if (line.hasOption("help") || commandName == null || commandName.equals("help")) { help(); System.exit(0); } Properties props = null; try { props = finder.findProperties(commandName); } catch (final IOException e1) { System.out.println("Unavailable command: " + commandName); help(false); System.exit(1); } if (props == null) { System.out.println("Unavailable command: " + commandName); help(false); System.exit(1); } // Shift the command name itself off the args list final String mainClass = props.getProperty(MAIN_CLASS_PROPERTY_NAME); if (mainClass == null) { throw new NullPointerException( "Command " + commandName + " did not specify a " + MAIN_CLASS_PROPERTY_NAME + " property"); } Class<?> clazz = null; try { clazz = Thread.currentThread().getContextClassLoader().loadClass(mainClass); } catch (final ClassNotFoundException cnfe) { throw new IllegalStateException( "Main class of command " + commandName + " does not exist: " + mainClass, cnfe); } Method mainMethod = null; try { mainMethod = clazz.getMethod("main", String[].class); } catch (final Exception e) { throw new IllegalStateException( "Main class of command " + commandName + " does not have a static main method: " + mainClass, e); } try { // WARNING, Definitely do *not* unwrap 'new Object[]{args}' to 'args' mainMethod.invoke(clazz, new Object[] { args }); } catch (final Throwable e) { if (line.hasOption("errors")) { e.printStackTrace(); } System.exit(-10); } } private String[] processSystemProperties(String[] args) { final ArrayList<String> argsList = new ArrayList<String>(); // We have to pre-screen for openejb.base as it has a direct affect // on where we look for the conf/system.properties file which we // need to read in and apply before we apply the command line -D // properties. Once SystemInstance.init() is called in the next // section of code, the openejb.base value is cemented and cannot // be changed. for (final String arg : args) { if (arg.indexOf("-Dopenejb.base") != -1) { final String prop = arg.substring(arg.indexOf("-D") + 2, arg.indexOf("=")); final String val = arg.substring(arg.indexOf("=") + 1); System.setProperty(prop, val); } } // get SystemInstance (the only static class in the system) // so we'll set up all the props in it SystemInstance systemInstance = null; try { SystemInstance.init(new Properties()); OptionsLog.install(); systemInstance = SystemInstance.get(); } catch (final Exception e) { e.printStackTrace(); System.exit(2); } // Now read in and apply the properties specified on the command line for (final String arg : args) { final int idx = arg.indexOf("-D"); final int eq = arg.indexOf("="); if (idx >= 0 && eq > idx) { final String prop = arg.substring(idx + 2, eq); final String val = arg.substring(eq + 1); System.setProperty(prop, val); systemInstance.setProperty(prop, val); } else { argsList.add(arg); } } args = (String[]) argsList.toArray(new String[argsList.size()]); return args; } //DMB: TODO: Delete me public static Enumeration<URL> doFindCommands() throws IOException { return Thread.currentThread().getContextClassLoader().getResources(BASE_PATH); } private static void help() { help(true); } private static void help(final boolean printHeader) { // Here we are using commons-cli to create the list of available commands // We actually use a different Options object to parse the 'openejb' command try { final Options options = new Options(); final ResourceFinder commandFinder = new ResourceFinder("META-INF"); final Map<String, Properties> commands = commandFinder.mapAvailableProperties("org.apache.openejb.cli"); for (final Map.Entry<String, Properties> command : commands.entrySet()) { if (command.getKey().contains(".")) { continue; } final Properties p = command.getValue(); final String description = p.getProperty(descriptionI18n, p.getProperty(descriptionBase)); options.addOption(command.getKey(), false, description); } final HelpFormatter formatter = new HelpFormatter(); final StringWriter sw = new StringWriter(); final PrintWriter pw = new PrintWriter(sw); final String syntax = "openejb <command> [options] [args]"; final String header = "\nAvailable commands:"; final String footer = "\n" + "Try 'openejb <command> --help' for help on a specific command.\n" + "For example 'openejb deploy --help'.\n" + "\n" + "Apache OpenEJB -- EJB Container System and Server.\n" + "For additional information, see http://tomee.apache.org\n" + "Bug Reports to <users@tomee.apache.org>"; if (!printHeader) { pw.append(header).append("\n\n"); formatter.printOptions(pw, 74, options, 1, 3); } else { formatter.printHelp(pw, 74, syntax, header, options, 1, 3, footer, false); } pw.flush(); // Fix up the commons-cli output to our liking. String text = sw.toString().replaceAll("\n -", "\n "); text = text.replace("\nApache OpenEJB", "\n\nApache OpenEJB"); System.out.print(text); } catch (final IOException e) { e.printStackTrace(); } } }