/**
* Searches for the next MPEG frame header from the current stream position on. This method
* advances the underlying input stream until it finds a valid frame header or the end of the
* stream is reached. In the former case a corresponding {@code AudioFrame} object is created. In
* the latter case there are no more headers, so the end of the stream is probably reached.
*
* @return the next {@code AudioFrame} or <b>null</b>
* @throws IOException if an IO error occurs
*/
public AudioFrame nextFrame() throws IOException {
AudioFrame frame = null;
while (!endOfStream && frame == null) {
findFrameSyncByte();
if (!endOfStream) {
HeaderBitField headerField = createHeaderField();
if (!endOfStream) {
frame = createHeader(headerField);
if (frame == null) {
pushBack(headerField);
} else {
System.arraycopy(headerField.toArray(), 0, header, 0, 3);
}
}
}
}
currentHeader = frame;
return frame;
}
/**
* Pushes the given header field back in the stream so that the bytes are read again. This method
* is called if an invalid header was detected. Then search has to continue at the next byte after
* the frame sync byte.
*
* @param field the header bit field with the invalid frame header
* @throws IOException if an error occurs
*/
private void pushBack(HeaderBitField field) throws IOException {
unread(field.toArray());
}
