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