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contributor license agreements. See the NOTICE file distributed with
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.filesystem;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.Iterator;
import java.util.List;
import org.apache.poi.poifs.common.POIFSConstants;
import org.apache.poi.poifs.property.RootProperty;
import org.apache.poi.poifs.storage.BATBlock;
import org.apache.poi.poifs.storage.BlockAllocationTableWriter;
import org.apache.poi.poifs.storage.HeaderBlock;
import org.apache.poi.poifs.storage.BATBlock.BATBlockAndIndex;
/**
* This class handles the MiniStream (small block store)
* in the NIO case for {@link NPOIFSFileSystem}
*/
public class NPOIFSMiniStore extends BlockStore
{
private NPOIFSFileSystem _filesystem;
private NPOIFSStream _mini_stream;
private List _sbat_blocks;
private HeaderBlock _header;
private RootProperty _root;
protected NPOIFSMiniStore(NPOIFSFileSystem filesystem, RootProperty root,
List sbats, HeaderBlock header)
{
this._filesystem = filesystem;
this._sbat_blocks = sbats;
this._header = header;
this._root = root;
this._mini_stream = new NPOIFSStream(filesystem, root.getStartBlock());
}
/**
* Load the block at the given offset.
*/
protected ByteBuffer getBlockAt(final int offset) throws IOException {
// Which big block is this?
int byteOffset = offset * POIFSConstants.SMALL_BLOCK_SIZE;
int bigBlockNumber = byteOffset / _filesystem.getBigBlockSize();
int bigBlockOffset = byteOffset % _filesystem.getBigBlockSize();
// Now locate the data block for it
Iterator it = _mini_stream.getBlockIterator();
for(int i=0; i