/**
* @param startByte
* @param endByte
* @return
* @throws Exception
* @return true if all the bytes between in the file between startByte and endByte are null, false
* otherwise
*/
private boolean isFilePortionNull(int startByte, int endByte) throws IOException {
logger.config("Checking file portion:" + Hex.asHex(startByte) + ":" + Hex.asHex(endByte));
FileInputStream fis = null;
FileChannel fc = null;
try {
fis = new FileInputStream(file);
fc = fis.getChannel();
fc.position(startByte);
ByteBuffer bb = ByteBuffer.allocateDirect(endByte - startByte);
fc.read(bb);
while (bb.hasRemaining()) {
if (bb.get() != 0) {
return false;
}
}
} finally {
if (fc != null) {
fc.close();
}
if (fis != null) {
fis.close();
}
}
return true;
}
/**
* Extracts the raw ID3v2 tag data into a file.
*
* <p>This provides access to the raw data before manipulation, the data is written from the start
* of the file to the start of the Audio Data. This is primarily useful for manipulating corrupted
* tags that are not (fully) loaded using the standard methods.
*
* @param outputFile to write the data to
* @return
* @throws TagNotFoundException
* @throws IOException
*/
public File extractID3v2TagDataIntoFile(File outputFile)
throws TagNotFoundException, IOException {
int startByte = (int) ((MP3AudioHeader) audioHeader).getMp3StartByte();
if (startByte >= 0) {
// Read byte into buffer
FileInputStream fis = new FileInputStream(file);
FileChannel fc = fis.getChannel();
ByteBuffer bb = ByteBuffer.allocate(startByte);
fc.read(bb);
// Write bytes to outputFile
FileOutputStream out = new FileOutputStream(outputFile);
out.write(bb.array());
out.close();
fc.close();
fis.close();
return outputFile;
}
throw new TagNotFoundException("There is no ID3v2Tag data in this file");
}
/**
* Read V2tag if exists
*
* <p>TODO:shouldn't we be handing TagExceptions:when will they be thrown
*
* @param file
* @param loadOptions
* @throws IOException
* @throws TagException
*/
private void readV2Tag(File file, int loadOptions, int startByte)
throws IOException, TagException {
// We know where the actual Audio starts so load all the file from start to that point into
// a buffer then we can read the IDv2 information without needing any more File I/O
if (startByte >= AbstractID3v2Tag.TAG_HEADER_LENGTH) {
logger.finer("Attempting to read id3v2tags");
FileInputStream fis = null;
FileChannel fc = null;
ByteBuffer bb;
try {
fis = new FileInputStream(file);
fc = fis.getChannel();
bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, startByte);
}
// #JAUDIOTAGGER-419:If reading networked file map can fail so just copy bytes instead
catch (IOException ioe) {
bb = ByteBuffer.allocate(startByte);
fc.read(bb, 0);
} finally {
if (fc != null) {
fc.close();
}
if (fis != null) {
fis.close();
}
}
try {
bb.rewind();
if ((loadOptions & LOAD_IDV2TAG) != 0) {
logger.config("Attempting to read id3v2tags");
try {
this.setID3v2Tag(new ID3v24Tag(bb, file.getName()));
} catch (TagNotFoundException ex) {
logger.config("No id3v24 tag found");
}
try {
if (id3v2tag == null) {
this.setID3v2Tag(new ID3v23Tag(bb, file.getName()));
}
} catch (TagNotFoundException ex) {
logger.config("No id3v23 tag found");
}
try {
if (id3v2tag == null) {
this.setID3v2Tag(new ID3v22Tag(bb, file.getName()));
}
} catch (TagNotFoundException ex) {
logger.config("No id3v22 tag found");
}
}
} finally {
// Workaround for 4724038 on Windows
bb.clear();
if (bb.isDirect() && !TagOptionSingleton.getInstance().isAndroid()) {
// Reflection substitute for following code:
// ((sun.nio.ch.DirectBuffer) bb).cleaner().clean();
// which causes exception on Android - Sun NIO classes are not available
try {
Class<?> clazz = Class.forName("sun.nio.ch.DirectBuffer");
Method cleanerMethod = clazz.getMethod("cleaner");
Object cleaner = cleanerMethod.invoke(bb); // cleaner = bb.cleaner()
if (cleaner != null) {
Method cleanMethod = cleaner.getClass().getMethod("clean");
cleanMethod.invoke(cleaner); // cleaner.clean()
}
} catch (ClassNotFoundException e) {
logger.severe("Could not load sun.nio.ch.DirectBuffer.");
} catch (NoSuchMethodException e) {
logger.severe("Could not invoke DirectBuffer method - " + e.getMessage());
} catch (InvocationTargetException e) {
logger.severe("Could not invoke DirectBuffer method - target exception");
} catch (IllegalAccessException e) {
logger.severe("Could not invoke DirectBuffer method - illegal access");
}
}
}
} else {
logger.config("Not enough room for valid id3v2 tag:" + startByte);
}
}