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.shell.ScreenContext;
023    
024    import java.io.Closeable;
025    import java.io.IOException;
026    import java.io.Writer;
027    
028    public class RenderWriter extends Writer implements ScreenContext {
029    
030      /** . */
031      private final ScreenContext out;
032    
033      /** . */
034      private final Closeable closeable;
035    
036      /** . */
037      private boolean closed;
038    
039      /** . */
040      private boolean empty;
041    
042      public RenderWriter(ScreenContext out) throws NullPointerException {
043        this(out, null);
044      }
045    
046      public RenderWriter(ScreenContext out, Closeable closeable) throws NullPointerException {
047        if (out == null) {
048          throw new NullPointerException("No null appendable expected");
049        }
050    
051        //
052        this.out = out;
053        this.empty = true;
054        this.closeable = closeable;
055      }
056    
057      public boolean isEmpty() {
058        return empty;
059      }
060    
061      public int getWidth() {
062        return out.getWidth();
063      }
064    
065      public int getHeight() {
066        return out.getHeight();
067      }
068    
069      public Class<Chunk> getConsumedType() {
070        return Chunk.class;
071      }
072    
073      public void write(Chunk chunk) throws IOException {
074        provide(chunk);
075      }
076    
077      public void provide(Chunk element) throws IOException {
078        if (element instanceof Text) {
079          Text text = (Text)element;
080          empty &= text.getText().length() == 0;
081        }
082        out.write(element);
083      }
084    
085      @Override
086      public void write(char[] cbuf, int off, int len) throws IOException {
087        if (closed) {
088          throw new IOException("Already closed");
089        }
090        if (len > 0) {
091          Text text = new Text();
092          text.buffer.append(cbuf, off, len);
093          provide(text);
094        }
095      }
096    
097      @Override
098      public void flush() throws IOException {
099        if (closed) {
100          throw new IOException("Already closed");
101        }
102        out.flush();
103      }
104    
105      @Override
106      public void close() throws IOException {
107        if (!closed) {
108          closed = true;
109          if (closeable != null) {
110            closeable.close();
111          }
112        }
113      }
114    }