src/java/org/apache/poi/poifs/storage/DocumentBlock.java - poi - Git at Google


 /* ====================================================================
  * The Apache Software License, Version 1.1
  *
  * Copyright (c) 2003 The Apache Software Foundation.  All rights
  * reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  *
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
  *
  * 3. The end-user documentation included with the redistribution,
  *    if any, must include the following acknowledgment:
  *       "This product includes software developed by the
  *        Apache Software Foundation (http://www.apache.org/)."
  *    Alternately, this acknowledgment may appear in the software itself,
  *    if and wherever such third-party acknowledgments normally appear.
  *
  * 4. The names "Apache" and "Apache Software Foundation" and
  *    "Apache POI" must not be used to endorse or promote products
  *    derived from this software without prior written permission. For
  *    written permission, please contact apache@apache.org.
  *
  * 5. Products derived from this software may not be called "Apache",
  *    "Apache POI", nor may "Apache" appear in their name, without
  *    prior written permission of the Apache Software Foundation.
  *
  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
  * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  * ====================================================================
  *
  * This software consists of voluntary contributions made by many
  * individuals on behalf of the Apache Software Foundation.  For more
  * information on the Apache Software Foundation, please see
  * <http://www.apache.org/>.
  */

 package org.apache.poi.poifs.storage;

 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;

 import java.util.Arrays;

 import org.apache.poi.poifs.common.POIFSConstants;
 import org.apache.poi.util.IOUtils;
 import org.apache.poi.util.IntegerField;
 import org.apache.poi.util.LittleEndian;
 import org.apache.poi.util.LittleEndianConsts;

 /**
  * A block of document data.
  *
  * @author Marc Johnson (mjohnson at apache dot org)
  */

 public class DocumentBlock
     extends BigBlock
 {
     private static final byte _default_value = ( byte ) 0xFF;
     private byte[]            _data;
     private int               _bytes_read;

     /**
      * create a document block from a raw data block
      *
      * @param block the raw data block
      *
      * @exception IOException
      */

     public DocumentBlock(final RawDataBlock block)
         throws IOException
     {
         _data       = block.getData();
         _bytes_read = _data.length;
     }

     /**
      * Create a single instance initialized with data.
      *
      * @param stream the InputStream delivering the data.
      *
      * @exception IOException
      */

     public DocumentBlock(final InputStream stream)
         throws IOException
     {
         this();
         int count = IOUtils.readFully(stream, _data);

         _bytes_read = (count == -1) ? 0
                                     : count;
     }

     /**
      * Create a single instance initialized with default values
      */

     private DocumentBlock()
     {
         _data = new byte[ POIFSConstants.BIG_BLOCK_SIZE ];
         Arrays.fill(_data, _default_value);
     }

     /**
      * Get the number of bytes read for this block
      *
      * @return bytes read into the block
      */

     public int size()
     {
         return _bytes_read;
     }

     /**
      * Was this a partially read block?
      *
      * @return true if the block was only partially filled with data
      */

     public boolean partiallyRead()
     {
         return _bytes_read != POIFSConstants.BIG_BLOCK_SIZE;
     }

     /**
      * @return the fill byte used
      */

     public static byte getFillByte()
     {
         return _default_value;
     }

     /**
      * convert a single long array into an array of DocumentBlock
      * instances
      *
      * @param array the byte array to be converted
      * @param size the intended size of the array (which may be smaller)
      *
      * @return an array of DocumentBlock instances, filled from the
      *         input array
      */

     public static DocumentBlock [] convert(final byte [] array,
                                            final int size)
     {
         DocumentBlock[] rval   =
             new DocumentBlock[ (size + POIFSConstants.BIG_BLOCK_SIZE - 1) / POIFSConstants.BIG_BLOCK_SIZE ];
         int             offset = 0;

         for (int k = 0; k < rval.length; k++)
         {
             rval[ k ] = new DocumentBlock();
             if (offset < array.length)
             {
                 int length = Math.min(POIFSConstants.BIG_BLOCK_SIZE,
                                       array.length - offset);

                 System.arraycopy(array, offset, rval[ k ]._data, 0, length);
                 if (length != POIFSConstants.BIG_BLOCK_SIZE)
                 {
                     Arrays.fill(rval[ k ]._data, length,
                                 POIFSConstants.BIG_BLOCK_SIZE,
                                 _default_value);
                 }
             }
             else
             {
                 Arrays.fill(rval[ k ]._data, _default_value);
             }
             offset += POIFSConstants.BIG_BLOCK_SIZE;
         }
         return rval;
     }

     /**
      * read data from an array of DocumentBlocks
      *
      * @param blocks the blocks to read from
      * @param buffer the buffer to write the data into
      * @param offset the offset into the array of blocks to read from
      */

     public static void read(final DocumentBlock [] blocks,
                             final byte [] buffer, final int offset)
     {
         int firstBlockIndex  = offset / POIFSConstants.BIG_BLOCK_SIZE;
         int firstBlockOffset = offset % POIFSConstants.BIG_BLOCK_SIZE;
         int lastBlockIndex   = (offset + buffer.length - 1)
                                / POIFSConstants.BIG_BLOCK_SIZE;

         if (firstBlockIndex == lastBlockIndex)
         {
             System.arraycopy(blocks[ firstBlockIndex ]._data,
                              firstBlockOffset, buffer, 0, buffer.length);
         }
         else
         {
             int buffer_offset = 0;

             System.arraycopy(blocks[ firstBlockIndex ]._data,
                              firstBlockOffset, buffer, buffer_offset,
                              POIFSConstants.BIG_BLOCK_SIZE
                              - firstBlockOffset);
             buffer_offset += POIFSConstants.BIG_BLOCK_SIZE - firstBlockOffset;
             for (int j = firstBlockIndex + 1; j < lastBlockIndex; j++)
             {
                 System.arraycopy(blocks[ j ]._data, 0, buffer, buffer_offset,
                                  POIFSConstants.BIG_BLOCK_SIZE);
                 buffer_offset += POIFSConstants.BIG_BLOCK_SIZE;
             }
             System.arraycopy(blocks[ lastBlockIndex ]._data, 0, buffer,
                              buffer_offset, buffer.length - buffer_offset);
         }
     }

     /* ********** START extension of BigBlock ********** */

     /**
      * Write the block's data to an OutputStream
      *
      * @param stream the OutputStream to which the stored data should
      *               be written
      *
      * @exception IOException on problems writing to the specified
      *            stream
      */

     void writeData(final OutputStream stream)
         throws IOException
     {
         doWriteData(stream, _data);
     }

     /* **********  END  extension of BigBlock ********** */
 }   // end public class DocumentBlock

	/* ====================================================================
	* The Apache Software License, Version 1.1
	*
	* Copyright (c) 2003 The Apache Software Foundation. All rights
	* reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	*
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	*
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in
	* the documentation and/or other materials provided with the
	* distribution.
	*
	* 3. The end-user documentation included with the redistribution,
	* if any, must include the following acknowledgment:
	* "This product includes software developed by the
	* Apache Software Foundation (http://www.apache.org/)."
	* Alternately, this acknowledgment may appear in the software itself,
	* if and wherever such third-party acknowledgments normally appear.
	*
	* 4. The names "Apache" and "Apache Software Foundation" and
	* "Apache POI" must not be used to endorse or promote products
	* derived from this software without prior written permission. For
	* written permission, please contact apache@apache.org.
	*
	* 5. Products derived from this software may not be called "Apache",
	* "Apache POI", nor may "Apache" appear in their name, without
	* prior written permission of the Apache Software Foundation.
	*
	* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
	* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
	* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
	* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
	* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
	* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	* SUCH DAMAGE.
	* ====================================================================
	*
	* This software consists of voluntary contributions made by many
	* individuals on behalf of the Apache Software Foundation. For more
	* information on the Apache Software Foundation, please see
	* <http://www.apache.org/>.
	*/

	package org.apache.poi.poifs.storage;

	import java.io.IOException;
	import java.io.InputStream;
	import java.io.OutputStream;

	import java.util.Arrays;

	import org.apache.poi.poifs.common.POIFSConstants;
	import org.apache.poi.util.IOUtils;
	import org.apache.poi.util.IntegerField;
	import org.apache.poi.util.LittleEndian;
	import org.apache.poi.util.LittleEndianConsts;

	/**
	* A block of document data.
	*
	* @author Marc Johnson (mjohnson at apache dot org)
	*/

	public class DocumentBlock
	extends BigBlock
	{
	private static final byte _default_value = ( byte ) 0xFF;
	private byte[] _data;
	private int _bytes_read;

	/**
	* create a document block from a raw data block
	*
	* @param block the raw data block
	*
	* @exception IOException
	*/

	public DocumentBlock(final RawDataBlock block)
	throws IOException
	{
	_data = block.getData();
	_bytes_read = _data.length;
	}

	/**
	* Create a single instance initialized with data.
	*
	* @param stream the InputStream delivering the data.
	*
	* @exception IOException
	*/

	public DocumentBlock(final InputStream stream)
	throws IOException
	{
	this();
	int count = IOUtils.readFully(stream, _data);

	_bytes_read = (count == -1) ? 0
	: count;
	}

	/**
	* Create a single instance initialized with default values
	*/

	private DocumentBlock()
	{
	_data = new byte[ POIFSConstants.BIG_BLOCK_SIZE ];
	Arrays.fill(_data, _default_value);
	}

	/**
	* Get the number of bytes read for this block
	*
	* @return bytes read into the block
	*/

	public int size()
	{
	return _bytes_read;
	}

	/**
	* Was this a partially read block?
	*
	* @return true if the block was only partially filled with data
	*/

	public boolean partiallyRead()
	{
	return _bytes_read != POIFSConstants.BIG_BLOCK_SIZE;
	}

	/**
	* @return the fill byte used
	*/

	public static byte getFillByte()
	{
	return _default_value;
	}

	/**
	* convert a single long array into an array of DocumentBlock
	* instances
	*
	* @param array the byte array to be converted
	* @param size the intended size of the array (which may be smaller)
	*
	* @return an array of DocumentBlock instances, filled from the
	* input array
	*/

	public static DocumentBlock [] convert(final byte [] array,
	final int size)
	{
	DocumentBlock[] rval =
	new DocumentBlock[ (size + POIFSConstants.BIG_BLOCK_SIZE - 1) / POIFSConstants.BIG_BLOCK_SIZE ];
	int offset = 0;

	for (int k = 0; k < rval.length; k++)
	{
	rval[ k ] = new DocumentBlock();
	if (offset < array.length)
	{
	int length = Math.min(POIFSConstants.BIG_BLOCK_SIZE,
	array.length - offset);

	System.arraycopy(array, offset, rval[ k ]._data, 0, length);
	if (length != POIFSConstants.BIG_BLOCK_SIZE)
	{
	Arrays.fill(rval[ k ]._data, length,
	POIFSConstants.BIG_BLOCK_SIZE,
	_default_value);
	}
	}
	else
	{
	Arrays.fill(rval[ k ]._data, _default_value);
	}
	offset += POIFSConstants.BIG_BLOCK_SIZE;
	}
	return rval;
	}

	/**
	* read data from an array of DocumentBlocks
	*
	* @param blocks the blocks to read from
	* @param buffer the buffer to write the data into
	* @param offset the offset into the array of blocks to read from
	*/

	public static void read(final DocumentBlock [] blocks,
	final byte [] buffer, final int offset)
	{
	int firstBlockIndex = offset / POIFSConstants.BIG_BLOCK_SIZE;
	int firstBlockOffset = offset % POIFSConstants.BIG_BLOCK_SIZE;
	int lastBlockIndex = (offset + buffer.length - 1)
	/ POIFSConstants.BIG_BLOCK_SIZE;

	if (firstBlockIndex == lastBlockIndex)
	{
	System.arraycopy(blocks[ firstBlockIndex ]._data,
	firstBlockOffset, buffer, 0, buffer.length);
	}
	else
	{
	int buffer_offset = 0;

	System.arraycopy(blocks[ firstBlockIndex ]._data,
	firstBlockOffset, buffer, buffer_offset,
	POIFSConstants.BIG_BLOCK_SIZE
	- firstBlockOffset);
	buffer_offset += POIFSConstants.BIG_BLOCK_SIZE - firstBlockOffset;
	for (int j = firstBlockIndex + 1; j < lastBlockIndex; j++)
	{
	System.arraycopy(blocks[ j ]._data, 0, buffer, buffer_offset,
	POIFSConstants.BIG_BLOCK_SIZE);
	buffer_offset += POIFSConstants.BIG_BLOCK_SIZE;
	}
	System.arraycopy(blocks[ lastBlockIndex ]._data, 0, buffer,
	buffer_offset, buffer.length - buffer_offset);
	}
	}

	/* ******** START extension of BigBlock ******** */

	/**
	* Write the block's data to an OutputStream
	*
	* @param stream the OutputStream to which the stored data should
	* be written
	*
	* @exception IOException on problems writing to the specified
	* stream
	*/

	void writeData(final OutputStream stream)
	throws IOException
	{
	doWriteData(stream, _data);
	}

	/* ******** END extension of BigBlock ******** */
	} // end public class DocumentBlock