001/* SimpleDoc.java -- 
002   Copyright (C) 2006 Free Software Foundation, Inc.
003
004This file is part of GNU Classpath.
005
006GNU Classpath is free software; you can redistribute it and/or modify
007it under the terms of the GNU General Public License as published by
008the Free Software Foundation; either version 2, or (at your option)
009any later version.
010
011GNU Classpath is distributed in the hope that it will be useful, but
012WITHOUT ANY WARRANTY; without even the implied warranty of
013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014General Public License for more details.
015
016You should have received a copy of the GNU General Public License
017along with GNU Classpath; see the file COPYING.  If not, write to the
018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
01902110-1301 USA.
020
021Linking this library statically or dynamically with other modules is
022making a combined work based on this library.  Thus, the terms and
023conditions of the GNU General Public License cover the whole
024combination.
025
026As a special exception, the copyright holders of this library give you
027permission to link this library with independent modules to produce an
028executable, regardless of the license terms of these independent
029modules, and to copy and distribute the resulting executable under
030terms of your choice, provided that you also meet, for each linked
031independent module, the terms and conditions of the license of that
032module.  An independent module is a module which is not derived from
033or based on this library.  If you modify this library, you may extend
034this exception to your version of the library, but you are not
035obligated to do so.  If you do not wish to do so, delete this
036exception statement from your version. */
037
038
039package javax.print;
040
041import java.io.ByteArrayInputStream;
042import java.io.CharArrayReader;
043import java.io.IOException;
044import java.io.InputStream;
045import java.io.Reader;
046import java.io.StringReader;
047
048import javax.print.attribute.AttributeSetUtilities;
049import javax.print.attribute.DocAttributeSet;
050
051/**
052 * Simple implementation of the <code>Doc</code> interface capable of handling 
053 * the predefined document flavors of <code>DocFlavor</code>.
054 * <p>
055 * This implementation can construct a reader or stream for the service from 
056 * the print data and ensures that always the same object is returned on each
057 * method call. It does simple checks that the supplied data matches the 
058 * specified flavor of the doc object and supports thread safe access.
059 * </p> 
060 * 
061 * @author Wolfgang Baer (WBaer@gmx.de)
062 */
063public final class SimpleDoc implements Doc
064{  
065  private final Object printData;
066  private final DocFlavor flavor;
067  private final DocAttributeSet attributes;
068  
069  private InputStream stream;
070  private Reader reader;
071
072  /**
073   * Constructs a SimpleDoc with the specified print data, doc flavor and doc attribute set.
074   * @param printData the object with the data to print.
075   * @param flavor the document flavor of the print data.
076   * @param attributes the attributes of the doc (may be <code>null</code>).
077   * 
078   * @throws IllegalArgumentException if either <code>printData</code> or
079   *   <code>flavor</code> are <code>null</code>, or the print data is not
080   *   supplied in the document format specified by the given flavor object.
081   */
082  public SimpleDoc(Object printData, DocFlavor flavor, 
083      DocAttributeSet attributes)
084  {
085    if (printData == null || flavor == null)
086      throw new IllegalArgumentException("printData/flavor may not be null");
087    
088    if (! (printData.getClass().getName().equals(
089           flavor.getRepresentationClassName())
090        || flavor.getRepresentationClassName().equals("java.io.Reader")
091           && printData instanceof Reader
092        || flavor.getRepresentationClassName().equals("java.io.InputStream")
093           && printData instanceof InputStream))
094      {
095        throw new IllegalArgumentException("data is not of declared flavor type");
096      }          
097    
098    this.printData = printData;
099    this.flavor = flavor;
100    
101    if (attributes != null)
102      this.attributes = AttributeSetUtilities.unmodifiableView(attributes);
103    else
104      this.attributes = null;
105    
106    stream = null;
107    reader = null;
108  }
109
110  /**
111   * Returns the unmodifiable view of the attributes of this doc object.
112   * <p>
113   * The attributes of this doc's attributes set overrides attributes of 
114   * the same category in the print job's attribute set. If an attribute 
115   * is not available in this doc's attributes set or <code>null</code>
116   * is returned the attributes of the same category of the print job are
117   * used. 
118   * </p>
119   * 
120   * @return The unmodifiable attributes set, or <code>null</code>.
121   */
122  public DocAttributeSet getAttributes()
123  {
124    return attributes;
125  }
126
127  /**
128   * Returns the flavor of this doc objects print data.
129   * 
130   * @return The document flavor.
131   */
132  public DocFlavor getDocFlavor()
133  {
134    return flavor;
135  }
136
137  /**
138   * Returns the print data of this doc object.
139   * <p>
140   * The returned object is an instance as described by the associated
141   * document flavor ({@link DocFlavor#getRepresentationClassName()})
142   * and can be cast to this representation class.
143   * </p>
144   * 
145   * @return The print data in the representation class.
146   * @throws IOException if representation class is a stream and I/O
147   * exception occures.
148   */
149  public Object getPrintData() throws IOException
150  {
151    return printData;
152  }
153
154  /**
155   * Returns a <code>Reader</code> object for extracting character print data
156   * from this document.
157   * <p>
158   * This method is supported if the document flavor is of type:
159   * <ul>
160   * <li><code>char[]</code></li>
161   * <li><code>java.lang.String</code></li>
162   * <li><code>java.io.Reader</code></li>
163   * </ul>
164   * otherwise this method returns <code>null</code>.
165   * </p> 
166   * 
167   * @return The <code>Reader</code> object, or <code>null</code>.
168   * 
169   * @throws IOException if an error occurs.
170   */
171  public Reader getReaderForText() throws IOException
172  {
173    synchronized (this)
174      {
175        // construct the reader if applicable on request
176        if (reader == null)
177          {
178            if (flavor instanceof DocFlavor.CHAR_ARRAY)
179              reader = new CharArrayReader((char[]) printData);
180            else if (flavor instanceof DocFlavor.STRING)
181              reader = new StringReader((String) printData);
182            else if (flavor instanceof DocFlavor.READER)
183              reader = (Reader) printData;
184          }
185        
186        return reader;
187      }   
188  }
189
190  /**
191   * Returns an <code>InputStream</code> object for extracting byte print data
192   * from this document.
193   * <p>
194   * This method is supported if the document flavor is of type:
195   * <ul>
196   * <li><code>byte[]</code></li>
197   * <li><code>java.io.InputStream</code></li>
198   * </ul>
199   * otherwise this method returns <code>null</code>.
200   * </p> 
201   * 
202   * @return The <code>InputStream</code> object, or <code>null</code>.
203   * 
204   * @throws IOException if an error occurs.
205   */
206  public InputStream getStreamForBytes() throws IOException
207  {
208    synchronized (this)
209      {
210        // construct the stream if applicable on request
211        if (stream == null)
212          {
213            if (flavor instanceof DocFlavor.BYTE_ARRAY)
214              stream = new ByteArrayInputStream((byte[]) printData);
215            else if (flavor instanceof DocFlavor.INPUT_STREAM)
216              stream = (InputStream) printData;
217          }
218        
219        return stream;
220      }    
221  }
222
223}