| /* ==================================================================== |
| Licensed to the Apache Software Foundation (ASF) under one or more |
| 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 |
| the License. You may obtain a copy of the License at |
| |
| 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 java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.util.Arrays; |
| |
| import org.apache.poi.poifs.common.POIFSBigBlockSize; |
| import org.apache.poi.poifs.common.POIFSConstants; |
| import org.apache.poi.util.IOUtils; |
| |
| /** |
| * A block of document data. |
| * |
| * @author Marc Johnson (mjohnson at apache dot org) |
| */ |
| public final 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 |
| { |
| super( |
| block.getBigBlockSize() == POIFSConstants.SMALLER_BIG_BLOCK_SIZE ? |
| POIFSConstants.SMALLER_BIG_BLOCK_SIZE_DETAILS : |
| POIFSConstants.LARGER_BIG_BLOCK_SIZE_DETAILS |
| ); |
| _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, POIFSBigBlockSize bigBlockSize) |
| throws IOException |
| { |
| this(bigBlockSize); |
| int count = IOUtils.readFully(stream, _data); |
| |
| _bytes_read = (count == -1) ? 0 |
| : count; |
| } |
| |
| /** |
| * Create a single instance initialized with default values |
| */ |
| |
| private DocumentBlock(POIFSBigBlockSize bigBlockSize) |
| { |
| super(bigBlockSize); |
| _data = new byte[ bigBlockSize.getBigBlockSize() ]; |
| 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 != bigBlockSize.getBigBlockSize(); |
| } |
| |
| /** |
| * @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 POIFSBigBlockSize bigBlockSize, |
| final byte [] array, |
| final int size) |
| { |
| DocumentBlock[] rval = |
| new DocumentBlock[ (size + bigBlockSize.getBigBlockSize() - 1) / bigBlockSize.getBigBlockSize() ]; |
| int offset = 0; |
| |
| for (int k = 0; k < rval.length; k++) |
| { |
| rval[ k ] = new DocumentBlock(bigBlockSize); |
| if (offset < array.length) |
| { |
| int length = Math.min(bigBlockSize.getBigBlockSize(), |
| array.length - offset); |
| |
| System.arraycopy(array, offset, rval[ k ]._data, 0, length); |
| if (length != bigBlockSize.getBigBlockSize()) |
| { |
| Arrays.fill(rval[ k ]._data, length, |
| bigBlockSize.getBigBlockSize(), |
| _default_value); |
| } |
| } |
| else |
| { |
| Arrays.fill(rval[ k ]._data, _default_value); |
| } |
| offset += bigBlockSize.getBigBlockSize(); |
| } |
| return rval; |
| } |
| |
| public static DataInputBlock getDataInputBlock(DocumentBlock[] blocks, int offset) { |
| if(blocks == null || blocks.length == 0) { |
| return null; |
| } |
| |
| // Key things about the size of the block |
| POIFSBigBlockSize bigBlockSize = blocks[0].bigBlockSize; |
| int BLOCK_SHIFT = bigBlockSize.getHeaderValue(); |
| int BLOCK_SIZE = bigBlockSize.getBigBlockSize(); |
| int BLOCK_MASK = BLOCK_SIZE - 1; |
| |
| // Now do the offset lookup |
| int firstBlockIndex = offset >> BLOCK_SHIFT; |
| int firstBlockOffset= offset & BLOCK_MASK; |
| return new DataInputBlock(blocks[firstBlockIndex]._data, firstBlockOffset); |
| } |
| |
| /* ********** 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 |
| |