/** Creates new Staff from the parentInput's input stream.
* The next object in the input stream must be of this type.
* This also reads all the enclosed MeasureStartTimeSlice objects
* which themselves contain the event TimeSlice and MusicSymbol objects.
*
* @param parentInput the parent RIFF object being used to read the input stream
*/
public static Staff newInstance(Riff parentInput)
{
Riff riffInput = new Riff(parentInput, "LIST");
riffInput.requireFOURCC(RIFF_ID);
Staff staff = new Staff(RiffStaffHeader.newInstance(riffInput));
if (riffInput.getBytesRemaining() <= 0)
// the staff is empty
return staff;
MeasureStartTimeSlice measureStart =
RiffMeasureStartTimeSlice.maybeNew(riffInput);
if (measureStart == null) {
// For some reason, the first chunk in this staff is not a
// measure start time slice. Create a fake one based
// on the previous staff system's end time
// DEBUG: must implement this! For now use start time of 0/1
measureStart = new MeasureStartTimeSlice(new Rational(0, 1), null);
}
while (true) {
if (staff.getMeasureStartCount() > 0 &&
staff.getMeasureStart
(staff.getMeasureStartCount() - 1).getStartTime().Equals
(measureStart.getStartTime()))
// This new measure start time is the same as the last one,
// so just continue using the last one.
// DEBUG: this still doesn't ensure increasing order
// DEBUG: This discards the tags in the newly read measure start
measureStart =
staff.getMeasureStart(staff.getMeasureStartCount() - 1);
else
staff.addMeasureStart(measureStart);
// Read event time slices until the next measure start time slice or
// end of the staff
RiffMeasureStartTimeSlice.addTimeSlices(riffInput, measureStart);
if (riffInput.getBytesRemaining() <= 0)
// reached the end of the staff
break;
// The previous call to readTimeSlices has already
// ensured that the next chunk is a measure start time slice.
measureStart = RiffMeasureStartTimeSlice.newInstance(riffInput);
}
return staff;
}
/** This reads event TimeSlice chunks from parentInput's input stream until the next
* measure start time slice or no more bytesRemaining in the parentInput,
* adding the TimeSlice objects to the measureStart's time slice list.
* When this reads the TimeSlice, it also adds the subsequent music
* symbols to it.
*
* @param parentInput the parent RIFF object being used to read the input stream
* @param measureStart the MeasureStartTimeSlice to which TimeSlice
* objects are added.
* @see TimeSlice
*/
public static void addTimeSlices(Riff parentInput, MeasureStartTimeSlice measureStart)
{
if (parentInput.getBytesRemaining() <= 0)
// This is a measure start time slice with nothing after it in the staff
return;
if (parentInput.peekFOURCC().Equals(RIFF_ID) &&
parentInput.peekFirstChunkBYTE() == MEASURE_START)
// The next chunk is already the start of a new measure
return;
TimeSlice timeSlice = RiffTimeSlice.maybeNew(parentInput);
if (timeSlice == null)
// For some reason, the first chunk after the measure start
// time slice is not an event time slice. Create a fake one with
// start time of 0/1.
// DEBUG: should mock up an input file and test this.
timeSlice = new TimeSlice(new Rational(0, 1), null);
while (true) {
if (measureStart.getTimeSliceCount() > 0 &&
measureStart.getTimeSlice
(measureStart.getTimeSliceCount() - 1).getStartTime().Equals
(timeSlice.getStartTime()))
// This new time slice start time is the same as the last one,
// so just continue using the last one.
// DEBUG: this still doesn't ensure increasing order
// DEBUG: This discards the tags in the newly read time slice
timeSlice =
measureStart.getTimeSlice(measureStart.getTimeSliceCount() - 1);
else
measureStart.addTimeSlice(timeSlice);
// Read music symbols until the next time slice or
// end of the staff.
RiffTimeSlice.addMusicSymbols(parentInput, timeSlice);
if (parentInput.getBytesRemaining() <= 0)
// reached the end of the staff
break;
// We know the next chunk is a time slice. Check whether it is
// a measure start.
if (parentInput.peekFirstChunkBYTE() == MEASURE_START)
// The next chunk is the start of a new measure
break;
// We have now ensured that the next chunk is an event time slice.
timeSlice = RiffTimeSlice.newInstance(parentInput);
}
}
/** Add the given measure start timeslice to the MeasureStartTimeSlice list.
* This does not call invalidate(), but you may need to before displaying.
*
* @param measureStart the MeasureStartTimeSlice to add. It is an error if
* this is already the child of an object.
* @throws HeirarchyException if the measureStart has already
* been added as a child to another object.
* @see #invalidate
*/
public void addMeasureStart(MeasureStartTimeSlice measureStart)
{
addChild(measureStart);
}
