1    
2    /* ====================================================================
3     * The Apache Software License, Version 1.1
4     *
5     * Copyright (c) 2002 The Apache Software Foundation.  All rights
6     * reserved.
7     *
8     * Redistribution and use in source and binary forms, with or without
9     * modification, are permitted provided that the following conditions
10    * are met:
11    *
12    * 1. Redistributions of source code must retain the above copyright
13    *    notice, this list of conditions and the following disclaimer.
14    *
15    * 2. Redistributions in binary form must reproduce the above copyright
16    *    notice, this list of conditions and the following disclaimer in
17    *    the documentation and/or other materials provided with the
18    *    distribution.
19    *
20    * 3. The end-user documentation included with the redistribution,
21    *    if any, must include the following acknowledgment:
22    *       "This product includes software developed by the
23    *        Apache Software Foundation (http://www.apache.org/)."
24    *    Alternately, this acknowledgment may appear in the software itself,
25    *    if and wherever such third-party acknowledgments normally appear.
26    *
27    * 4. The names "Apache" and "Apache Software Foundation" and
28    *    "Apache POI" must not be used to endorse or promote products
29    *    derived from this software without prior written permission. For
30    *    written permission, please contact apache@apache.org.
31    *
32    * 5. Products derived from this software may not be called "Apache",
33    *    "Apache POI", nor may "Apache" appear in their name, without
34    *    prior written permission of the Apache Software Foundation.
35    *
36    * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
37    * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
38    * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
39    * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
40    * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41    * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
42    * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
43    * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
44    * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
45    * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
46    * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
47    * SUCH DAMAGE.
48    * ====================================================================
49    *
50    * This software consists of voluntary contributions made by many
51    * individuals on behalf of the Apache Software Foundation.  For more
52    * information on the Apache Software Foundation, please see
53    * <http://www.apache.org/>.
54    */
55   
56   package org.apache.poi.poifs.storage;
57   
58   import org.apache.poi.poifs.common.POIFSConstants;
59   
60   import java.io.*;
61   
62   /**
63    * A big block created from an InputStream, holding the raw data
64    *
65    * @author Marc Johnson (mjohnson at apache dot org
66    */
67   
68   public class RawDataBlock
69       implements ListManagedBlock
70   {
71       private byte[]  _data;
72       private boolean _eof;
73   
74       /**
75        * Constructor RawDataBlock
76        *
77        * @param stream the InputStream from which the data will be read
78        *
79        * @exception IOException on I/O errors, and if an insufficient
80        *            amount of data is read
81        */
82   
83       public RawDataBlock(final InputStream stream)
84           throws IOException
85       {
86           _data = new byte[ POIFSConstants.BIG_BLOCK_SIZE ];
87           int count = stream.read(_data);
88   
89           if (count == -1)
90           {
91               _eof = true;
92           }
93           else if (count != POIFSConstants.BIG_BLOCK_SIZE)
94           {
95               String type = " byte" + ((count == 1) ? ("")
96                                                     : ("s"));
97   
98               throw new IOException("Unable to read entire block; " + count
99                                     + type + " read; expected "
100                                    + POIFSConstants.BIG_BLOCK_SIZE + " bytes");
101          }
102          else
103          {
104              _eof = false;
105          }
106      }
107  
108      /**
109       * When we read the data, did we hit end of file?
110       *
111       * @return true if no data was read because we were at the end of
112       *         the file, else false
113       *
114       * @exception IOException
115       */
116  
117      public boolean eof()
118          throws IOException
119      {
120          return _eof;
121      }
122  
123      /* ********** START implementation of ListManagedBlock ********** */
124  
125      /**
126       * Get the data from the block
127       *
128       * @return the block's data as a byte array
129       *
130       * @exception IOException if there is no data
131       */
132  
133      public byte [] getData()
134          throws IOException
135      {
136          if (eof())
137          {
138              throw new IOException("Cannot return empty data");
139          }
140          return _data;
141      }
142  
143      /* **********  END  implementation of ListManagedBlock ********** */
144  }   // end public class RawDataBlock
145  
146