| 1 | package org.farng.mp3; |
| 2 | |
| 3 | import org.farng.mp3.id3.ID3v2_2; |
| 4 | import org.farng.mp3.id3.ID3v2_3; |
| 5 | import org.farng.mp3.id3.ID3v2_4; |
| 6 | import org.farng.mp3.object.AbstractMP3Object; |
| 7 | |
| 8 | import java.io.IOException; |
| 9 | import java.io.RandomAccessFile; |
| 10 | import java.util.ArrayList; |
| 11 | import java.util.Iterator; |
| 12 | import java.util.List; |
| 13 | |
| 14 | /** |
| 15 | * This class is contained in the <code>AbstractMP3Fragment</code> and represents the actual data of tags. It contains |
| 16 | * default get/set methods for all data objects. The data is represented as an ArrayList of <code>MP3Object</code>. |
| 17 | * ID3v2 tags have frames. Lyrics3 tags have fields. ID3v1 tags do not have fragments. |
| 18 | * |
| 19 | * @author Eric Farng |
| 20 | * @version $Revision: 1.6 $ |
| 21 | */ |
| 22 | public abstract class AbstractMP3FragmentBody extends AbstractMP3FileItem { |
| 23 | |
| 24 | private static final int SIZE_OBJECT_LIST = 16; |
| 25 | private static final int SIZE_BRIEF_DESCRIPTION = 64; |
| 26 | private static final int SIZE_DESCRIPTION = 256; |
| 27 | /** |
| 28 | * list of <code>MP3Object</code> |
| 29 | */ |
| 30 | private List objectList = new ArrayList(AbstractMP3FragmentBody.SIZE_OBJECT_LIST); |
| 31 | |
| 32 | /** |
| 33 | * Creates a new MP3FragmentBody object. |
| 34 | */ |
| 35 | protected AbstractMP3FragmentBody() { |
| 36 | super(); |
| 37 | setupObjectList(); |
| 38 | } |
| 39 | |
| 40 | /** |
| 41 | * Creates a new AbstractMP3FragmentBody object. |
| 42 | */ |
| 43 | protected AbstractMP3FragmentBody(final AbstractMP3FragmentBody copyObject) { |
| 44 | super(copyObject); |
| 45 | final Iterator iterator = copyObject.iterator(); |
| 46 | while (iterator.hasNext()) { |
| 47 | final AbstractMP3Object oldObject = (AbstractMP3Object) iterator.next(); |
| 48 | final AbstractMP3Object newObject = (AbstractMP3Object) TagUtility.copyObject(oldObject); |
| 49 | objectList.add(newObject); |
| 50 | } |
| 51 | } |
| 52 | |
| 53 | /** |
| 54 | * This method calls <code>toString</code> for all it's objects and appends them without any newline characters. |
| 55 | * |
| 56 | * @return brief description string |
| 57 | */ |
| 58 | public String getBriefDescription() { |
| 59 | final StringBuffer stringBuffer = new StringBuffer(AbstractMP3FragmentBody.SIZE_BRIEF_DESCRIPTION); |
| 60 | final Iterator iterator = objectList.listIterator(); |
| 61 | while (iterator.hasNext()) { |
| 62 | final AbstractMP3Object object = (AbstractMP3Object) iterator.next(); |
| 63 | final String objectToString = object.toString(); |
| 64 | if (objectToString != null && objectToString.length() > 0) { |
| 65 | final String identifier = object.getIdentifier(); |
| 66 | stringBuffer.append(identifier); |
| 67 | stringBuffer.append("=\""); |
| 68 | stringBuffer.append(objectToString); |
| 69 | stringBuffer.append("\"; "); |
| 70 | } |
| 71 | } |
| 72 | return stringBuffer.toString(); |
| 73 | } |
| 74 | |
| 75 | /** |
| 76 | * This method calls <code>toString</code> for all it's objects and appends them. It contains new line characters |
| 77 | * and is more suited for display purposes |
| 78 | * |
| 79 | * @return formatted description string |
| 80 | */ |
| 81 | public String getDescription() { |
| 82 | final StringBuffer stringBuffer = new StringBuffer(AbstractMP3FragmentBody.SIZE_DESCRIPTION); |
| 83 | final Iterator iterator = objectList.listIterator(); |
| 84 | while (iterator.hasNext()) { |
| 85 | final AbstractMP3Object object = (AbstractMP3Object) iterator.next(); |
| 86 | final String identifier = object.getIdentifier(); |
| 87 | stringBuffer.append(identifier); |
| 88 | stringBuffer.append(" = "); |
| 89 | final String string = object.toString(); |
| 90 | stringBuffer.append(string); |
| 91 | stringBuffer.append(TagConstant.SEPERATOR_LINE); |
| 92 | } |
| 93 | final String toString = stringBuffer.toString(); |
| 94 | return toString.trim(); |
| 95 | } |
| 96 | |
| 97 | public Iterator getObjectListIterator() { |
| 98 | return objectList.listIterator(); |
| 99 | } |
| 100 | |
| 101 | /** |
| 102 | * Sets the all objects of identifier type to <code>object</code> argument. |
| 103 | * |
| 104 | * @param identifier <code>MP3Object</code> identifier |
| 105 | * @param object new object value |
| 106 | */ |
| 107 | public void setObject(final String identifier, final Object object) { |
| 108 | final Iterator iterator = objectList.listIterator(); |
| 109 | while (iterator.hasNext()) { |
| 110 | final AbstractMP3Object abstractMP3Object = (AbstractMP3Object) iterator.next(); |
| 111 | final String currentIdentifier = abstractMP3Object.getIdentifier(); |
| 112 | if (currentIdentifier.equals(identifier)) { |
| 113 | abstractMP3Object.setValue(object); |
| 114 | } |
| 115 | } |
| 116 | } |
| 117 | |
| 118 | /** |
| 119 | * Returns the object of the <code>MP3Object</code> with the specified <code>identifier</code> |
| 120 | * |
| 121 | * @param identifier <code>MP3Object</code> identifier |
| 122 | * |
| 123 | * @return the object of the <code>MP3Object</code> with the specified <code>identifier</code> |
| 124 | */ |
| 125 | public Object getObject(final String identifier) { |
| 126 | Object object = null; |
| 127 | final Iterator iterator = objectList.listIterator(); |
| 128 | while (iterator.hasNext()) { |
| 129 | final AbstractMP3Object abstractMP3Object = (AbstractMP3Object) iterator.next(); |
| 130 | final String currentIdentifier = abstractMP3Object.getIdentifier(); |
| 131 | if (currentIdentifier.equals(identifier)) { |
| 132 | object = abstractMP3Object.getValue(); |
| 133 | } |
| 134 | } |
| 135 | return object; |
| 136 | } |
| 137 | |
| 138 | /** |
| 139 | * Returns the estimated size in bytes of this object if it was to be written to file. This is not guaranteed to be |
| 140 | * accurate 100% of the time. |
| 141 | * |
| 142 | * @return estimated size in bytes of this object |
| 143 | */ |
| 144 | public int getSize() { |
| 145 | //todo get this working 100% of the time |
| 146 | int size = 0; |
| 147 | final Iterator iterator = objectList.listIterator(); |
| 148 | while (iterator.hasNext()) { |
| 149 | final AbstractMP3Object object = (AbstractMP3Object) iterator.next(); |
| 150 | size += object.getSize(); |
| 151 | } |
| 152 | return size; |
| 153 | } |
| 154 | |
| 155 | /** |
| 156 | * Returns true if this instance and its entire <code>MP3Object</code> array list is a subset of the argument. This |
| 157 | * class is a subset if it is the same class as the argument. |
| 158 | * |
| 159 | * @param object object to determine subset of |
| 160 | * |
| 161 | * @return true if this instance and its entire object array list is a subset of the argument. |
| 162 | */ |
| 163 | public boolean isSubsetOf(final Object object) { |
| 164 | if (!super.isSubsetOf(object)) { |
| 165 | return false; |
| 166 | } |
| 167 | if (!(object instanceof AbstractMP3FragmentBody)) { |
| 168 | return false; |
| 169 | } |
| 170 | final List superset = ((AbstractMP3FragmentBody) object).objectList; |
| 171 | final int objectListSize = objectList.size(); |
| 172 | for (int i = 0; i < objectListSize; i++) { |
| 173 | final AbstractMP3Object abstractMP3Object = (AbstractMP3Object) objectList.get(i); |
| 174 | if (abstractMP3Object.getValue() != null && !superset.contains(abstractMP3Object)) { |
| 175 | return false; |
| 176 | } |
| 177 | } |
| 178 | return true; |
| 179 | } |
| 180 | |
| 181 | /** |
| 182 | * Returns true if this object and its entire <code>MP3Object</code> array list equals the argument. This object is |
| 183 | * equal to the argument only if they are the same class. |
| 184 | * |
| 185 | * @param obj object to determine equality of |
| 186 | * |
| 187 | * @return true if this object and its entire <code>MP3Object</code> array list equals the argument. |
| 188 | */ |
| 189 | public boolean equals(final Object obj) { |
| 190 | if (!(obj instanceof AbstractMP3FragmentBody)) { |
| 191 | return false; |
| 192 | } |
| 193 | final AbstractMP3FragmentBody abstractMP3FragmentBody = (AbstractMP3FragmentBody) obj; |
| 194 | if (!objectList.equals(abstractMP3FragmentBody.objectList)) { |
| 195 | return false; |
| 196 | } |
| 197 | return super.equals(obj); |
| 198 | } |
| 199 | |
| 200 | /** |
| 201 | * Returns an iterator of the <code>MP3Object</code> object list. |
| 202 | * |
| 203 | * @return iterator of the <code>MP3Object</code> object list. |
| 204 | */ |
| 205 | public Iterator iterator() { |
| 206 | return objectList.iterator(); |
| 207 | } |
| 208 | |
| 209 | protected void appendToObjectList(final AbstractMP3Object object) { |
| 210 | objectList.add(object); |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * Read the data from the given file into this object. The file needs to have its file pointer in the correct |
| 215 | * location. |
| 216 | * |
| 217 | * @param file file to read from |
| 218 | * |
| 219 | * @throws IOException on any I/O error |
| 220 | * @throws InvalidTagException if there is any error in the data format. |
| 221 | */ |
| 222 | public void read(final RandomAccessFile file) throws IOException, InvalidTagException { |
| 223 | final int size = readHeader(file); |
| 224 | final byte[] buffer = new byte[size]; |
| 225 | file.read(buffer); |
| 226 | final Iterator iterator = objectList.listIterator(); |
| 227 | int offset = 0; |
| 228 | while (iterator.hasNext()) { |
| 229 | // sanjay@revasoft.com start bug fix |
| 230 | if (offset > size - 1) { |
| 231 | throw new InvalidTagException("Invalid size for Frame Body"); |
| 232 | } |
| 233 | |
| 234 | // sanjay@revasoft.com end bug fix |
| 235 | final AbstractMP3Object object = (AbstractMP3Object) iterator.next(); |
| 236 | object.readByteArray(buffer, offset); |
| 237 | offset += object.getSize(); |
| 238 | } |
| 239 | } |
| 240 | |
| 241 | /** |
| 242 | * Calls <code>toString</code> for all <code>MP3Object</code> objects and creates a string with a new line |
| 243 | * character. |
| 244 | * |
| 245 | * @return description string |
| 246 | */ |
| 247 | public String toString() { |
| 248 | final StringBuffer stringBuffer = new StringBuffer(AbstractMP3FragmentBody.SIZE_DESCRIPTION); |
| 249 | final String thisIdentifier = getIdentifier(); |
| 250 | stringBuffer.append(thisIdentifier); |
| 251 | stringBuffer.append(TagConstant.SEPERATOR_LINE); |
| 252 | final Iterator iterator = objectList.listIterator(); |
| 253 | while (iterator.hasNext()) { |
| 254 | final AbstractMP3Object object = (AbstractMP3Object) iterator.next(); |
| 255 | final String objectIdentifier = object.getIdentifier(); |
| 256 | stringBuffer.append(objectIdentifier); |
| 257 | stringBuffer.append(" = "); |
| 258 | final String string = object.toString(); |
| 259 | stringBuffer.append(string); |
| 260 | stringBuffer.append(TagConstant.SEPERATOR_LINE); |
| 261 | } |
| 262 | return stringBuffer.toString(); |
| 263 | } |
| 264 | |
| 265 | /** |
| 266 | * Write the contents of this object to the file at the position it is currently at. |
| 267 | * |
| 268 | * @param file destination file |
| 269 | * |
| 270 | * @throws IOException on any I/O error |
| 271 | */ |
| 272 | public void write(final RandomAccessFile file) throws IOException { |
| 273 | final int size = getSize(); |
| 274 | writeHeader(file, size); |
| 275 | final Iterator iterator = objectList.listIterator(); |
| 276 | while (iterator.hasNext()) { |
| 277 | final AbstractMP3Object object = (AbstractMP3Object) iterator.next(); |
| 278 | final byte[] buffer = object.writeByteArray(); |
| 279 | file.write(buffer); |
| 280 | } |
| 281 | } |
| 282 | |
| 283 | /** |
| 284 | * Reads the header for the fragment body. The header contains things such as the length. |
| 285 | * |
| 286 | * @param file file to read the header from. |
| 287 | * |
| 288 | * @return size of body in bytes as stated in the header. |
| 289 | * |
| 290 | * @throws IOException on any I/O error |
| 291 | * @throws InvalidTagException if there is any error in the data format. |
| 292 | */ |
| 293 | protected abstract int readHeader(RandomAccessFile file) throws IOException, InvalidTagException; |
| 294 | |
| 295 | /** |
| 296 | * Create the order of <code>MP3Object</code> objects that this body expects. This method needs to be overwritten. |
| 297 | */ |
| 298 | protected abstract void setupObjectList(); |
| 299 | |
| 300 | /** |
| 301 | * Write the body header to the file at the current file position. |
| 302 | * |
| 303 | * @param file file to write to |
| 304 | * @param size number of bytes the body contains. |
| 305 | * |
| 306 | * @throws IOException on any I/O error |
| 307 | */ |
| 308 | protected abstract void writeHeader(RandomAccessFile file, int size) throws IOException; |
| 309 | |
| 310 | protected static boolean has6ByteHeader() { |
| 311 | final Exception exception = new Exception(); |
| 312 | final StackTraceElement[] stackArray = exception.getStackTrace(); |
| 313 | final String id3v2_2name = ID3v2_2.class.getName(); |
| 314 | final String id3v2_3name = ID3v2_3.class.getName(); |
| 315 | final String id3v2_4name = ID3v2_4.class.getName(); |
| 316 | boolean has6ByteHeader = false; |
| 317 | boolean withinTag = false; |
| 318 | for (int i = stackArray.length - 1; i >= 0; i--) { |
| 319 | final String className = stackArray[i].getClassName(); |
| 320 | if (id3v2_2name.equals(className)) { |
| 321 | has6ByteHeader = true; |
| 322 | withinTag = true; |
| 323 | } else if (id3v2_3name.equals(className)) { |
| 324 | has6ByteHeader = false; |
| 325 | withinTag = true; |
| 326 | } else if (id3v2_4name.equals(className)) { |
| 327 | has6ByteHeader = false; |
| 328 | withinTag = true; |
| 329 | } |
| 330 | } |
| 331 | if (!withinTag) { |
| 332 | throw new UnsupportedOperationException("FragmentBody not called within ID3v2 tag."); |
| 333 | } |
| 334 | return has6ByteHeader; |
| 335 | } |
| 336 | } |