| |
| /* ==================================================================== |
| * 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.*; |
| |
| import java.util.*; |
| |
| import org.apache.poi.poifs.common.POIFSConstants; |
| import org.apache.poi.util.IntegerField; |
| import org.apache.poi.util.LittleEndian; |
| import org.apache.poi.util.LittleEndianConsts; |
| import org.apache.poi.util.LongField; |
| import org.apache.poi.util.ShortField; |
| |
| /** |
| * The block containing the archive header |
| * |
| * @author Marc Johnson (mjohnson at apache dot org) |
| */ |
| |
| public class HeaderBlockReader |
| implements HeaderBlockConstants |
| { |
| |
| // number of big block allocation table blocks (int) |
| private IntegerField _bat_count; |
| |
| // start of the property set block (int index of the property set |
| // chain's first big block) |
| private IntegerField _property_start; |
| |
| // start of the small block allocation table (int index of small |
| // block allocation table's first big block) |
| private IntegerField _sbat_start; |
| |
| // big block index for extension to the big block allocation table |
| private IntegerField _xbat_start; |
| private IntegerField _xbat_count; |
| private byte[] _data; |
| |
| /** |
| * create a new HeaderBlockReader from an InputStream |
| * |
| * @param stream the source InputStream |
| * |
| * @exception IOException on errors or bad data |
| */ |
| |
| public HeaderBlockReader(final InputStream stream) |
| throws IOException |
| { |
| _data = new byte[ POIFSConstants.BIG_BLOCK_SIZE ]; |
| int byte_count = stream.read(_data); |
| |
| if (byte_count != POIFSConstants.BIG_BLOCK_SIZE) |
| { |
| String type = " byte" + ((byte_count == 1) ? ("") |
| : ("s")); |
| |
| throw new IOException("Unable to read entire header; " |
| + byte_count + type + " read; expected " |
| + POIFSConstants.BIG_BLOCK_SIZE + " bytes"); |
| } |
| |
| // verify signature |
| LongField signature = new LongField(_signature_offset, _data); |
| |
| if (signature.get() != _signature) |
| { |
| throw new IOException("Invalid header signature; read " |
| + signature.get() + ", expected " |
| + _signature); |
| } |
| _bat_count = new IntegerField(_bat_count_offset, _data); |
| _property_start = new IntegerField(_property_start_offset, _data); |
| _sbat_start = new IntegerField(_sbat_start_offset, _data); |
| _xbat_start = new IntegerField(_xbat_start_offset, _data); |
| _xbat_count = new IntegerField(_xbat_count_offset, _data); |
| } |
| |
| /** |
| * get start of Property Table |
| * |
| * @return the index of the first block of the Property Table |
| */ |
| |
| public int getPropertyStart() |
| { |
| return _property_start.get(); |
| } |
| |
| /** |
| * @return start of small block allocation table |
| */ |
| |
| public int getSBATStart() |
| { |
| return _sbat_start.get(); |
| } |
| |
| /** |
| * @return number of BAT blocks |
| */ |
| |
| public int getBATCount() |
| { |
| return _bat_count.get(); |
| } |
| |
| /** |
| * @return BAT array |
| */ |
| |
| public int [] getBATArray() |
| { |
| int[] result = new int[ _max_bats_in_header ]; |
| int offset = _bat_array_offset; |
| |
| for (int j = 0; j < _max_bats_in_header; j++) |
| { |
| result[ j ] = LittleEndian.getInt(_data, offset); |
| offset += LittleEndianConsts.INT_SIZE; |
| } |
| return result; |
| } |
| |
| /** |
| * @return XBAT count |
| */ |
| |
| public int getXBATCount() |
| { |
| return _xbat_count.get(); |
| } |
| |
| /** |
| * @return XBAT index |
| */ |
| |
| public int getXBATIndex() |
| { |
| return _xbat_start.get(); |
| } |
| } // end public class HeaderBlockReader |
| |