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.command;
021    
022    import java.io.IOException;
023    
024    /**
025     * A pipe command.
026     *
027     * @param <C> the consumed generic type
028     * @param <P> the produced generic type
029     */
030    public abstract class PipeCommand<C, P> {
031    
032      /** . */
033      protected InvocationContext<P> context;
034    
035      public final boolean isPiped() {
036        return context.isPiped();
037      }
038    
039      void doOpen(InvocationContext<P> context) {
040        this.context = context;
041    
042        //
043        open();
044      }
045    
046      /**
047       * Open pipe.
048       */
049      public void open() throws ScriptException {
050      }
051    
052      /**
053       * Extends the throw clause of the {@link org.crsh.io.Consumer#provide(Object)} method.
054       *
055       * @param element the provided element
056       * @throws ScriptException any script exception
057       * @throws IOException any io exception
058       */
059      public void provide(C element) throws ScriptException, IOException {
060      }
061    
062      /**
063       * Flush pipe.
064       *
065       * @throws ScriptException any script exception
066       * @throws IOException any io exception
067       */
068      public void flush() throws ScriptException, IOException {
069        context.flush();
070      }
071    
072      /**
073       * Close pipe.
074       *
075       * @throws ScriptException any script exception
076       */
077      public void close() throws ScriptException {
078      }
079    }