001    /*
002     * Copyright (C) 2010 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;
021    
022    import org.crsh.shell.ShellProcessContext;
023    import org.crsh.shell.ShellResponse;
024    import org.slf4j.Logger;
025    import org.slf4j.LoggerFactory;
026    
027    /**
028     * @author <a href="mailto:julien.viet@exoplatform.com">Julien Viet</a>
029     * @version $Revision$
030     */
031    class CRaSHProcessFactory {
032    
033      /** . */
034      private static final Logger log = LoggerFactory.getLogger(CRaSH.class);
035    
036      /** . */
037      private final CRaSH crash;
038    
039      /** . */
040      private final String request;
041    
042      CRaSHProcessFactory(CRaSH crash, String request) {
043        this.crash = crash;
044        this.request = request;
045      }
046    
047      private static class SimpleProcess extends CRaSHProcess {
048    
049        /** . */
050        private final ShellResponse response;
051    
052        private SimpleProcess(CRaSH crash, String request, ShellResponse response) {
053          super(crash, request);
054          this.response = response;
055        }
056    
057        @Override
058        ShellResponse invoke(ShellProcessContext context) {
059          return response;
060        }
061      }
062    
063      CRaSHProcess create() {
064    
065        //
066        if ("bye".equals(request)) {
067          return new SimpleProcess(crash, request, new ShellResponse.Close());
068        } else {
069    
070          // Create AST
071          Parser parser = new Parser(request);
072          AST ast = parser.parse();
073    
074          //
075          if (ast instanceof AST.Expr) {
076            AST.Expr expr = (AST.Expr)ast;
077    
078            // Create commands first
079            try {
080              return expr.create(crash, request);
081            } catch (CreateCommandException e) {
082              return new SimpleProcess(crash, request, e.getResponse());
083            }
084          } else {
085            return new SimpleProcess(crash, request, new ShellResponse.NoCommand());
086          }
087        }
088      }
089    }