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this work for additional information regarding copyright ownership.
The ASF licenses this file to You under the Apache License, Version 2.0
(the "License"); you may not use this file except in compliance with
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http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
==================================================================== */
package org.apache.poi.poifs.storage;
import org.apache.poi.poifs.common.POIFSBigBlockSize;
import org.apache.poi.poifs.common.POIFSConstants;
import org.apache.poi.poifs.filesystem.BATManaged;
import org.apache.poi.poifs.filesystem.POIFSDocument;
import org.apache.poi.poifs.property.RootProperty;
import java.util.*;
import java.io.*;
/**
* This class implements storage for writing the small blocks used by
* small documents.
*
* @author Marc Johnson (mjohnson at apache dot org)
*/
public class SmallBlockTableWriter
implements BlockWritable, BATManaged
{
private BlockAllocationTableWriter _sbat;
private List _small_blocks;
private int _big_block_count;
private RootProperty _root;
/**
* Creates new SmallBlockTable
*
* @param documents a List of POIFSDocument instances
* @param root the Filesystem's root property
*/
public SmallBlockTableWriter(final POIFSBigBlockSize bigBlockSize,
final List documents,
final RootProperty root)
{
_sbat = new BlockAllocationTableWriter(bigBlockSize);
_small_blocks = new ArrayList();
_root = root;
Iterator iter = documents.iterator();
while (iter.hasNext())
{
POIFSDocument doc = ( POIFSDocument ) iter.next();
BlockWritable[] blocks = doc.getSmallBlocks();
if (blocks.length != 0)
{
doc.setStartBlock(_sbat.allocateSpace(blocks.length));
for (int j = 0; j < blocks.length; j++)
{
_small_blocks.add(blocks[ j ]);
}
} else {
doc.setStartBlock(POIFSConstants.END_OF_CHAIN);
}
}
_sbat.simpleCreateBlocks();
_root.setSize(_small_blocks.size());
_big_block_count = SmallDocumentBlock.fill(bigBlockSize,_small_blocks);
}
/**
* Get the number of SBAT blocks
*
* @return number of SBAT big blocks
*/
public int getSBATBlockCount()
{
return (_big_block_count + 15) / 16;
}
/**
* Get the SBAT
*
* @return the Small Block Allocation Table
*/
public BlockAllocationTableWriter getSBAT()
{
return _sbat;
}
/* ********** START implementation of BATManaged ********** */
/**
* Return the number of BigBlock's this instance uses
*
* @return count of BigBlock instances
*/
public int countBlocks()
{
return _big_block_count;
}
/**
* Set the start block for this instance
*
* @param start_block
*/
public void setStartBlock(int start_block)
{
_root.setStartBlock(start_block);
}
/* ********** END implementation of BATManaged ********** */
/* ********** START implementation of BlockWritable ********** */
/**
* Write the storage to an OutputStream
*
* @param stream the OutputStream to which the stored data should
* be written
*
* @exception IOException on problems writing to the specified
* stream
*/
public void writeBlocks(final OutputStream stream)
throws IOException
{
Iterator iter = _small_blocks.iterator();
while (iter.hasNext())
{
(( BlockWritable ) iter.next()).writeBlocks(stream);
}
}
/* ********** END implementation of BlockWritable ********** */
}