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.text;
021
022import org.crsh.stream.Consumer;
023
024import java.io.IOException;
025import java.util.LinkedList;
026
027/**
028 * A <code>Consumer&lt;Object&gt;</code> that renders the object stream to a {@link ScreenContext}.
029 */
030public class ScreenContextConsumer implements Consumer<Object> {
031
032  /** Buffers objects of the same kind. */
033  private final LinkedList<Object> buffer = new LinkedList<Object>();
034
035  /** . */
036  private Renderer renderable = null;
037
038  /** . */
039  private final RenderAppendable out;
040
041  public ScreenContextConsumer(ScreenContext out) {
042    this.out = new RenderAppendable(out);
043  }
044
045  public Class<Object> getConsumedType() {
046    return Object.class;
047  }
048
049  public void provide(Object element) throws IOException {
050    Renderer current = Renderer.getRenderable(element.getClass());
051    if (current == null) {
052      send();
053      if (element instanceof CharSequence) {
054        out.append((CharSequence)element);
055      } else if (element instanceof CLS) {
056        out.cls();
057      } else if (element instanceof Style) {
058        out.append((Style)element);
059      } else {
060        out.append(element.toString());
061      }
062    } else {
063      if (renderable != null && !current.equals(renderable)) {
064        send();
065      }
066      buffer.addLast(element);
067      renderable = current;
068    }
069  }
070
071  public void flush() throws IOException {
072    send();
073    out.flush();
074  }
075
076  public void send() throws IOException {
077    if (buffer.size() > 0) {
078      LineRenderer renderer = renderable.renderer(buffer.iterator());
079      renderer.render(out);
080      buffer.clear();
081      renderable = null;
082    }
083  }
084}