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 */
019package org.crsh.shell.impl.command.spi;
020
021import java.util.Map;
022
023/**
024 * Resolve commands.
025 *
026 * @author Julien Viet
027 */
028public interface CommandResolver {
029
030  /**
031   * @return the known command names by this resolver, the returned map keys are the command names
032   *         and the values are the corresponding one line description of the command
033   */
034  Iterable<Map.Entry<String, String>> getDescriptions();
035
036  /**
037   * Attempt to obtain a command. Null is returned when such command does not exist.
038   *
039   * @param name the command name
040   * @return the command shell
041   * @throws CommandException if an error occured preventing the command creation
042   * @throws NullPointerException if the name argument is null
043   */
044  Command<?> resolveCommand(String name) throws CommandException, NullPointerException;
045}