001    /*
002     * Copyright (C) 2003-2009 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.command;
021    
022    import org.crsh.shell.io.ShellPrinter;
023    
024    import java.util.Map;
025    
026    /**
027     * The invocation context provided to a command during the invocation phase. The invocation context provides the
028     * various interactions that a command can perform with its context during its invocation.
029     *
030     * @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a>
031     * @version $Revision$
032     */
033    public interface InvocationContext<C, P> extends CommandContext {
034    
035      /**
036       * Returns the term width in chars. When the value is not positive it means the value could not be determined.
037       *
038       * @return the term width
039       */
040      int getWidth();
041    
042      String getProperty(String propertyName);
043    
044      String readLine(String msg, boolean echo);
045    
046      ShellPrinter getWriter();
047    
048      /**
049       * Returns true if the command is involved in a pipe operation and receives a stream.
050       *
051       * @return true if the command is involved in a pipe
052       */
053      boolean isPiped();
054    
055      /**
056       * Returns an iterator over the stream of consumed items.
057       * @return the consumed items
058       * @throws IllegalStateException if the command is not involved in a pipe operation
059       */
060      Iterable<C> consume() throws IllegalStateException;
061    
062      void produce(P product);
063    
064    }