001 /*
002 * Copyright (C) 2012 eXo Platform SAS.
003 *
004 * This is free software; you can redistribute it and/or modify it
005 * under the terms of the GNU Lesser General Public License as
006 * published by the Free Software Foundation; either version 2.1 of
007 * the License, or (at your option) any later version.
008 *
009 * This software is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 *
014 * You should have received a copy of the GNU Lesser General Public
015 * License along with this software; if not, write to the Free
016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
018 */
019
020 package org.crsh.shell.impl.command;
021
022 import org.crsh.lang.LanguageCommandResolver;
023 import org.crsh.lang.spi.Language;
024 import org.crsh.shell.impl.command.spi.Command;
025 import org.crsh.shell.impl.command.spi.CommandException;
026 import org.crsh.shell.impl.command.spi.CommandResolver;
027 import org.crsh.plugin.PluginContext;
028 import org.crsh.shell.impl.command.system.SystemResolver;
029
030 import java.security.Principal;
031 import java.util.ArrayList;
032 import java.util.LinkedHashMap;
033 import java.util.Map;
034
035 public class CRaSH {
036
037 /** . */
038 final PluginContext context;
039
040 /** . */
041 final LanguageCommandResolver scriptResolver;
042
043 /** . */
044 private final ArrayList<CommandResolver> resolvers = new ArrayList<CommandResolver>();
045
046 /** . */
047 final ArrayList<Language> langs = new ArrayList<Language>();
048
049 /**
050 * Create a new CRaSH.
051 *
052 * @param context the plugin context
053 * @throws NullPointerException if the context argument is null
054 */
055 public CRaSH(PluginContext context) throws NullPointerException {
056 this.context = context;
057 this.scriptResolver = new LanguageCommandResolver(context);
058
059 // Add the resolver plugins
060 for (CommandResolver resolver : context.getPlugins(CommandResolver.class)) {
061 resolvers.add(resolver);
062 }
063 for (Language lang : context.getPlugins(Language.class)) {
064 if (lang.isActive()) {
065 langs.add(lang);
066 }
067 }
068
069 //
070 resolvers.add(scriptResolver);
071 resolvers.add(SystemResolver.INSTANCE);
072 }
073
074 public CRaSHSession createSession(Principal user) {
075 return new CRaSHSession(this, user);
076 }
077
078 /**
079 * Returns the plugin context.
080 *
081 * @return the plugin context
082 */
083 public PluginContext getContext() {
084 return context;
085 }
086
087 /**
088 * Attempt to obtain a command instance. Null is returned when such command does not exist.
089 *
090 * @param name the command name
091 * @return a command instance
092 * @throws org.crsh.shell.impl.command.spi.CommandException if an error occured preventing the command creation
093 * @throws NullPointerException if the name argument is null
094 */
095 public Command<?> getCommand(String name) throws CommandException, NullPointerException {
096 if (name == null) {
097 throw new NullPointerException("No null name accepted");
098 }
099 for (int i = 0;i < resolvers.size();i++) {
100 Command<?> command = resolvers.get(i).resolveCommand(name);
101 if (command != null) {
102 return command;
103 }
104 }
105 return null;
106 }
107
108 public Iterable<Map.Entry<String, String>> getCommands() {
109 LinkedHashMap<String, String> names = new LinkedHashMap<String, String>();
110 for (int i = 0;i < resolvers.size();i++) {
111 for (Map.Entry<String, String> entry : resolvers.get(i).getDescriptions()) {
112 names.put(entry.getKey(), entry.getValue());
113 }
114 }
115 return names.entrySet();
116 }
117 }