/**
* if the ID3v2.4 tag header's values have been modified, then resize the raw binary buffer and
* store the new values there. When finished, reset the dirty flag to indicate that the buffer is
* up to date, and the tag header is now ready to be saved to the .mp3 file.
*/
public void setBuffer() {
System.arraycopy(version.getIdBytes(), 0, header, 0, ID3TagVersion.NUM_ID_BYTES);
header[5] =
(byte)
(unsynchronization
? header[5] | TAG_HEADER_UNSYNCHRONIZATION_MASK
: header[5] & ~TAG_HEADER_UNSYNCHRONIZATION_MASK);
header[5] =
(byte)
(extendedHeaderPresent
? header[5] | TAG_HEADER_EXTENDED_HEADER_PRESENT_MASK
: header[5] & ~TAG_HEADER_EXTENDED_HEADER_PRESENT_MASK);
header[5] =
(byte)
(experimentalIndicator
? header[5] | TAG_HEADER_EXPERIMENTAL_INDICATOR_MASK
: header[5] & ~TAG_HEADER_EXPERIMENTAL_INDICATOR_MASK);
header[5] =
(byte)
(footerPresent
? header[5] | TAG_HEADER_FOOTER_PRESENT_MASK
: header[5] & ~TAG_HEADER_FOOTER_PRESENT_MASK);
System.arraycopy(ID3v24FrameBodyUtility.synchsafeIntToBytes(tagSize), 0, header, 6, 4);
dirty = false;
}
/**
* gets a string representation of the ID3v2.4 tag header showing the values of the standard
* ID3v2.4 tag header's fields.
*
* @return a string representation of the ID3v2.4 tag header.
*/
@Override
public String toString() {
StringBuffer buffer = new StringBuffer();
buffer.append("ID3v2.4 tag header\n");
buffer.append(" bytes..................: " + header.length + " bytes\n");
buffer.append(" " + ID3v24FrameBodyUtility.hex(header, 27) + "\n");
buffer.append(" version................: " + version + "\n");
buffer.append(" tag size...............: " + tagSize + " bytes\n");
buffer.append(" unsynchronization......: " + unsynchronization + "\n");
buffer.append(" extended header present: " + extendedHeaderPresent + "\n");
buffer.append(" experimental indicator.: " + experimentalIndicator + "\n");
buffer.append(" footer present.........: " + footerPresent);
return buffer.toString();
}
/**
* This constructor is called when reading in an existing ID3v2.4 tag header from an .mp3 file.
*
* @param inputStream input stream pointing to the end of the standard ID3v2.4 tag header in the
* .mp3 file.
* @throws IOException if the tag header can not be loaded from the .mp3 file.
*/
public ID3v24TagHeader(InputStream inputStream) throws IOException {
this();
// read in the rest of the ID3v2.4 tag header (the bytes after the ID3v2.4 id)
byte[] buffer = new byte[TAG_HEADER_SIZE - ID3TagVersion.NUM_ID_BYTES];
if (inputStream.read(buffer) != buffer.length)
throw new IOException("Unable to read in the ID3v2.4 tag header from the .mp3 file.");
System.arraycopy(buffer, 0, header, ID3TagVersion.NUM_ID_BYTES, buffer.length);
// parse the flags
unsynchronization = (buffer[0] & TAG_HEADER_UNSYNCHRONIZATION_MASK) != 0;
extendedHeaderPresent = (buffer[0] & TAG_HEADER_EXTENDED_HEADER_PRESENT_MASK) != 0;
experimentalIndicator = (buffer[0] & TAG_HEADER_EXPERIMENTAL_INDICATOR_MASK) != 0;
footerPresent = (buffer[0] & TAG_HEADER_FOOTER_PRESENT_MASK) != 0;
// get the size of the tag (not counting this header)
tagSize = ID3v24FrameBodyUtility.bytesToSynchsafeInt(buffer, 1);
dirty = false;
}
