javax.sound.midi
public class: Sequence [javadoc |
source]
java.lang.Object
javax.sound.midi.Sequence
A
Sequence is a data structure containing musical
information (often an entire song or composition) that can be played
back by a
Sequencer object. Specifically, the
Sequence contains timing
information and one or more tracks. Each
track consists of a
series of MIDI events (such as note-ons, note-offs, program changes, and meta-events).
The sequence's timing information specifies the type of unit that is used
to time-stamp the events in the sequence.
A Sequence can be created from a MIDI file by reading the file
into an input stream and invoking one of the getSequence methods of
MidiSystem . A sequence can also be built from scratch by adding new
Tracks to an empty Sequence, and adding
MidiEvent objects to these Tracks.
Also see:
- Sequencer#setSequence(java.io.InputStream stream)
- Sequencer#setSequence(Sequence sequence)
- Track#add(MidiEvent)
- MidiFileFormat
- author:
Kara - Kytle
| Field Summary |
|---|
| public static final float | PPQ | The tempo-based timing type, for which the resolution is expressed in pulses (ticks) per quarter note. |
| public static final float | SMPTE_24 | The SMPTE-based timing type with 24 frames per second (resolution is expressed in ticks per frame). |
| public static final float | SMPTE_25 | The SMPTE-based timing type with 25 frames per second (resolution is expressed in ticks per frame). |
| public static final float | SMPTE_30DROP | The SMPTE-based timing type with 29.97 frames per second (resolution is expressed in ticks per frame). |
| public static final float | SMPTE_30 | The SMPTE-based timing type with 30 frames per second (resolution is expressed in ticks per frame). |
| protected float | divisionType | The timing division type of the sequence. |
| protected int | resolution | The timing resolution of the sequence. |
| protected Vector<Track> | tracks | The MIDI tracks in this sequence. |
| Constructor: |
|---|
 public Sequence(float divisionType,
int resolution) throws InvalidMidiDataException {
if (divisionType == PPQ)
this.divisionType = PPQ;
else if (divisionType == SMPTE_24)
this.divisionType = SMPTE_24;
else if (divisionType == SMPTE_25)
this.divisionType = SMPTE_25;
else if (divisionType == SMPTE_30DROP)
this.divisionType = SMPTE_30DROP;
else if (divisionType == SMPTE_30)
this.divisionType = SMPTE_30;
else throw new InvalidMidiDataException("Unsupported division type: " + divisionType);
this.resolution = resolution;
}
Constructs a new MIDI sequence with the specified timing division
type and timing resolution. The division type must be one of the
recognized MIDI timing types. For tempo-based timing,
divisionType is PPQ (pulses per quarter note) and
the resolution is specified in ticks per beat. For SMTPE timing,
divisionType specifies the number of frames per
second and the resolution is specified in ticks per frame.
The sequence will contain no initial tracks. Tracks may be
added to or removed from the sequence using #createTrack
and #deleteTrack . |
public Sequence(float divisionType,
int resolution,
int numTracks) throws InvalidMidiDataException {
if (divisionType == PPQ)
this.divisionType = PPQ;
else if (divisionType == SMPTE_24)
this.divisionType = SMPTE_24;
else if (divisionType == SMPTE_25)
this.divisionType = SMPTE_25;
else if (divisionType == SMPTE_30DROP)
this.divisionType = SMPTE_30DROP;
else if (divisionType == SMPTE_30)
this.divisionType = SMPTE_30;
else throw new InvalidMidiDataException("Unsupported division type: " + divisionType);
this.resolution = resolution;
for (int i = 0; i < numTracks; i++) {
tracks.addElement(new Track());
}
} Constructs a new MIDI sequence with the specified timing division
type, timing resolution, and number of tracks. The division type must be one of the
recognized MIDI timing types. For tempo-based timing,
divisionType is PPQ (pulses per quarter note) and
the resolution is specified in ticks per beat. For SMTPE timing,
divisionType specifies the number of frames per
second and the resolution is specified in ticks per frame.
The sequence will be initialized with the number of tracks specified by
numTracks. These tracks are initially empty (i.e.
they contain only the meta-event End of Track).
The tracks may be retrieved for editing using the #getTracks
method. Additional tracks may be added, or existing tracks removed,
using #createTrack and #deleteTrack . |
| Methods from java.lang.Object: |
|---|
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
| Method from javax.sound.midi.Sequence Detail: |
|---|
public Track createTrack() {
Track track = new Track();
tracks.addElement(track);
return track;
} Creates a new, initially empty track as part of this sequence.
The track initially contains the meta-event End of Track.
The newly created track is returned. All tracks in the sequence
may be retrieved using #getTracks . Tracks may be
removed from the sequence using #deleteTrack . |
public boolean deleteTrack(Track track) {
synchronized(tracks) {
return tracks.removeElement(track);
}
} Removes the specified track from the sequence. |
public float getDivisionType() {
return divisionType;
} Obtains the timing division type for this sequence. |
public long getMicrosecondLength() {
return com.sun.media.sound.MidiUtils.tick2microsecond(this, getTickLength(), null);
} Obtains the duration of this sequence, expressed in microseconds. |
public Patch[] getPatchList() {
// $$kk: 04.09.99: need to implement!!
return new Patch[0];
} Obtains a list of patches referenced in this sequence.
This patch list may be used to load the required
Instrument objects
into a Synthesizer . |
public int getResolution() {
return resolution;
} Obtains the timing resolution for this sequence.
If the sequence's division type is PPQ, the resolution is specified in ticks per beat.
For SMTPE timing, the resolution is specified in ticks per frame. |
public long getTickLength() {
long length = 0;
synchronized(tracks) {
for(int i=0; i< tracks.size(); i++ ) {
long temp = ((Track)tracks.elementAt(i)).ticks();
if( temp >length ) {
length = temp;
}
}
return length;
}
} Obtains the duration of this sequence, expressed in MIDI ticks. |
public Track[] getTracks() {
return (Track[]) tracks.toArray(new Track[tracks.size()]);
} Obtains an array containing all the tracks in this sequence.
If the sequence contains no tracks, an array of length 0 is returned. |