1 2 /* ==================================================================== 3 * The Apache Software License, Version 1.1 4 * 5 * Copyright (c) 2002 The Apache Software Foundation. All rights 6 * reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. The end-user documentation included with the redistribution, 21 * if any, must include the following acknowledgment: 22 * "This product includes software developed by the 23 * Apache Software Foundation (http://www.apache.org/)." 24 * Alternately, this acknowledgment may appear in the software itself, 25 * if and wherever such third-party acknowledgments normally appear. 26 * 27 * 4. The names "Apache" and "Apache Software Foundation" and 28 * "Apache POI" must not be used to endorse or promote products 29 * derived from this software without prior written permission. For 30 * written permission, please contact apache@apache.org. 31 * 32 * 5. Products derived from this software may not be called "Apache", 33 * "Apache POI", nor may "Apache" appear in their name, without 34 * prior written permission of the Apache Software Foundation. 35 * 36 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED 37 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 38 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 39 * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR 40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 42 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 43 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 44 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 45 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 46 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 47 * SUCH DAMAGE. 48 * ==================================================================== 49 * 50 * This software consists of voluntary contributions made by many 51 * individuals on behalf of the Apache Software Foundation. For more 52 * information on the Apache Software Foundation, please see 53 * <http://www.apache.org/>. 54 */ 55 56 package org.apache.poi.poifs.storage; 57 58 import java.io.*; 59 60 import java.util.*; 61 62 /** 63 * A simple implementation of BlockList 64 * 65 * @author Marc Johnson (mjohnson at apache dot org 66 */ 67 68 class BlockListImpl 69 implements BlockList 70 { 71 private ListManagedBlock[] _blocks; 72 private BlockAllocationTableReader _bat; 73 74 /** 75 * Constructor BlockListImpl 76 */ 77 78 protected BlockListImpl() 79 { 80 _blocks = new ListManagedBlock[ 0 ]; 81 _bat = null; 82 } 83 84 /** 85 * provide blocks to manage 86 * 87 * @param blocks blocks to be managed 88 */ 89 90 protected void setBlocks(final ListManagedBlock [] blocks) 91 { 92 _blocks = blocks; 93 } 94 95 /* ********** START implementation of BlockList ********** */ 96 97 /** 98 * remove the specified block from the list 99 * 100 * @param index the index of the specified block; if the index is 101 * out of range, that's ok 102 */ 103 104 public void zap(final int index) 105 { 106 if ((index >= 0) && (index < _blocks.length)) 107 { 108 _blocks[ index ] = null; 109 } 110 } 111 112 /** 113 * remove and return the specified block from the list 114 * 115 * @param index the index of the specified block 116 * 117 * @return the specified block 118 * 119 * @exception IOException if the index is out of range or has 120 * already been removed 121 */ 122 123 public ListManagedBlock remove(final int index) 124 throws IOException 125 { 126 ListManagedBlock result = null; 127 128 try 129 { 130 result = _blocks[ index ]; 131 if (result == null) 132 { 133 throw new IOException("block[ " + index 134 + " ] already removed"); 135 } 136 _blocks[ index ] = null; 137 } 138 catch (ArrayIndexOutOfBoundsException ignored) 139 { 140 throw new IOException("Cannot remove block[ " + index 141 + " ]; out of range"); 142 } 143 return result; 144 } 145 146 /** 147 * get the blocks making up a particular stream in the list. The 148 * blocks are removed from the list. 149 * 150 * @param startBlock the index of the first block in the stream 151 * 152 * @return the stream as an array of correctly ordered blocks 153 * 154 * @exception IOException if blocks are missing 155 */ 156 157 public ListManagedBlock [] fetchBlocks(final int startBlock) 158 throws IOException 159 { 160 if (_bat == null) 161 { 162 throw new IOException( 163 "Improperly initialized list: no block allocation table provided"); 164 } 165 return _bat.fetchBlocks(startBlock, this); 166 } 167 168 /** 169 * set the associated BlockAllocationTable 170 * 171 * @param bat the associated BlockAllocationTable 172 * 173 * @exception IOException 174 */ 175 176 public void setBAT(final BlockAllocationTableReader bat) 177 throws IOException 178 { 179 if (_bat != null) 180 { 181 throw new IOException( 182 "Attempt to replace existing BlockAllocationTable"); 183 } 184 _bat = bat; 185 } 186 187 /* ********** END implementation of BlockList ********** */ 188 } // end package-scope class BlockListImpl 189 190