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
020package org.crsh.command;
021
022import org.crsh.stream.Filter;
023import org.crsh.util.Utils;
024
025import java.io.IOException;
026
027/**
028 * A command pipe.
029 *
030 * @param <C> the consumed generic type
031 * @param <P> the produced generic type
032 */
033public abstract class Pipe<C, P> implements Filter<C, P, InvocationContext<P>> {
034
035  /** . */
036  protected InvocationContext<P> context;
037
038  public final Class<P> getProducedType() {
039    return (Class<P>)Utils.resolveToClass(getClass(), Pipe.class, 1);
040  }
041
042  public final Class<C> getConsumedType() {
043    return (Class<C>)Utils.resolveToClass(getClass(), Pipe.class, 0);
044  }
045
046  public void open(InvocationContext<P> consumer) throws Exception {
047    this.context = consumer;
048
049    //
050    open();
051  }
052
053  /**
054   * Open pipe.
055   */
056  public void open() throws Exception {
057  }
058
059  public void provide(C element) throws Exception {
060  }
061
062  /**
063   * Flush pipe.
064   *
065   * @throws IOException any io exception
066   */
067  public void flush() throws IOException {
068    context.flush();
069  }
070
071  /**
072   * Close pipe.
073   *
074   * @throws Exception any exception
075   */
076  public void close() throws Exception {
077    context.close();
078  }
079}