AutoCloseable
, MidiDevice
public interface Sequencer extends MidiDevice
sequence
is known as a sequencer. A MIDI sequence contains lists of time-stamped MIDI data, such as might be read from a standard MIDI file. Most sequencers also provide functions for creating and editing sequences. The Sequencer
interface includes methods for the following basic MIDI sequencer operations:
Sequencer
has access to: Modifier and Type | Interface | Description |
---|---|---|
static class |
Sequencer.SyncMode |
A SyncMode object represents one of the ways in which a MIDI sequencer's notion of time can be synchronized with a master or slave device. |
MidiDevice.Info
Modifier and Type | Field | Description |
---|---|---|
static final int |
LOOP_CONTINUOUSLY |
A value indicating that looping should continue indefinitely rather than complete after a specific number of loops. |
Modifier and Type | Method | Description |
---|---|---|
int[] |
addControllerEventListener |
Registers a controller event listener to receive notification whenever the sequencer processes a control-change event of the requested type or types. |
boolean |
addMetaEventListener |
Registers a meta-event listener to receive notification whenever a meta-event is encountered in the sequence and processed by the sequencer. |
int |
getLoopCount() |
Obtains the number of repetitions for playback. |
long |
getLoopEndPoint() |
Obtains the end position of the loop, in MIDI ticks. |
long |
getLoopStartPoint() |
Obtains the start position of the loop, in MIDI ticks. |
Sequencer.SyncMode |
getMasterSyncMode() |
Obtains the current master synchronization mode for this sequencer. |
Sequencer.SyncMode[] |
getMasterSyncModes() |
Obtains the set of master synchronization modes supported by this sequencer. |
long |
getMicrosecondLength() |
Obtains the length of the current sequence, expressed in microseconds, or 0 if no sequence is set. |
long |
getMicrosecondPosition() |
Obtains the current position in the sequence, expressed in microseconds. |
Sequence |
getSequence() |
Obtains the sequence on which the Sequencer is currently operating. |
Sequencer.SyncMode |
getSlaveSyncMode() |
Obtains the current slave synchronization mode for this sequencer. |
Sequencer.SyncMode[] |
getSlaveSyncModes() |
Obtains the set of slave synchronization modes supported by the sequencer. |
float |
getTempoFactor() |
Returns the current tempo factor for the sequencer. |
float |
getTempoInBPM() |
Obtains the current tempo, expressed in beats per minute. |
float |
getTempoInMPQ() |
Obtains the current tempo, expressed in microseconds per quarter note. |
long |
getTickLength() |
Obtains the length of the current sequence, expressed in MIDI ticks, or 0 if no sequence is set. |
long |
getTickPosition() |
Obtains the current position in the sequence, expressed in MIDI ticks. |
boolean |
getTrackMute |
Obtains the current mute state for a track. |
boolean |
getTrackSolo |
Obtains the current solo state for a track. |
boolean |
isRecording() |
Indicates whether the Sequencer is currently recording. |
boolean |
isRunning() |
Indicates whether the Sequencer is currently running. |
void |
recordDisable |
Disables recording to the specified track. |
void |
recordEnable |
Prepares the specified track for recording events received on a particular channel. |
int[] |
removeControllerEventListener |
Removes a controller event listener's interest in one or more types of controller event. |
void |
removeMetaEventListener |
Removes the specified meta-event listener from this sequencer's list of registered listeners, if in fact the listener is registered. |
void |
setLoopCount |
Sets the number of repetitions of the loop for playback. |
void |
setLoopEndPoint |
Sets the last MIDI tick that will be played in the loop. |
void |
setLoopStartPoint |
Sets the first MIDI tick that will be played in the loop. |
void |
setMasterSyncMode |
Sets the source of timing information used by this sequencer. |
void |
setMicrosecondPosition |
Sets the current position in the sequence, expressed in microseconds. |
void |
setSequence |
Sets the current sequence on which the sequencer operates. |
void |
setSequence |
Sets the current sequence on which the sequencer operates. |
void |
setSlaveSyncMode |
Sets the slave synchronization mode for the sequencer. |
void |
setTempoFactor |
Scales the sequencer's actual playback tempo by the factor provided. |
void |
setTempoInBPM |
Sets the tempo in beats per minute. |
void |
setTempoInMPQ |
Sets the tempo in microseconds per quarter note. |
void |
setTickPosition |
Sets the current sequencer position in MIDI ticks. |
void |
setTrackMute |
Sets the mute state for a track. |
void |
setTrackSolo |
Sets the solo state for a track. |
void |
start() |
Starts playback of the MIDI data in the currently loaded sequence. |
void |
startRecording() |
Starts recording and playback of MIDI data. |
void |
stop() |
Stops recording, if active, and playback of the currently loaded sequence, if any. |
void |
stopRecording() |
Stops recording, if active. |
close, getDeviceInfo, getMaxReceivers, getMaxTransmitters, getReceiver, getReceivers, getTransmitter, getTransmitters, isOpen, open
static final int LOOP_CONTINUOUSLY
void setSequence(Sequence sequence) throws InvalidMidiDataException
This method can be called even if the Sequencer
is closed.
sequence
- the sequence to be loadedInvalidMidiDataException
- if the sequence contains invalid MIDI data, or is not supportedvoid setSequence(InputStream stream) throws IOException, InvalidMidiDataException
This method can be called even if the Sequencer
is closed.
stream
- stream containing MIDI file dataIOException
- if an I/O exception occurs during reading of the streamInvalidMidiDataException
- if invalid data is encountered in the stream, or the stream is not supportedSequence getSequence()
This method can be called even if the Sequencer
is closed.
null
if no sequence is currently setvoid start()
setLoopCount
. After that, or if the loop count is 0, playback will continue to play to the end of the sequence. The implementation ensures that the synthesizer is brought to a consistent state when jumping to the loop start point by sending appropriate controllers, pitch bend, and program change events.
IllegalStateException
- if the Sequencer
is closedvoid stop()
IllegalStateException
- if the Sequencer
is closedboolean isRunning()
false
. The Sequencer starts running when eitherstart()
or startRecording()
is called. isRunning
then returns true
until playback of the sequence completes or stop()
is called.true
if the Sequencer is running, otherwise false
void startRecording()
Note that tracks are not by default enabled for recording. In order to record MIDI data, at least one track must be specifically enabled for recording.
IllegalStateException
- if the Sequencer
is closedvoid stopRecording()
IllegalStateException
- if the Sequencer
is closedboolean isRecording()
false
. The Sequencer begins recording when startRecording()
is called, and then returns true
until stop()
or stopRecording()
is called.true
if the Sequencer is recording, otherwise false
void recordEnable(Track track, int channel)
track
- the track to which events will be recordedchannel
- the channel on which events will be received. If -1 is specified for the channel value, the track will receive data from all channels.IllegalArgumentException
- thrown if the track is not part of the current sequencevoid recordDisable(Track track)
track
- the track to disable for recording, or null
to disable recording for all tracksfloat getTempoInBPM()
void setTempoInBPM(float bpm)
bpm
- desired new tempo in beats per minutefloat getTempoInMPQ()
void setTempoInMPQ(float mpq)
mpq
- desired new tempo in microseconds per quarter notevoid setTempoFactor(float factor)
getTempoInMPQ()
and getTempoInBPM()
. Those values indicate the tempo prior to scaling. Note that the tempo factor cannot be adjusted when external synchronization is used. In that situation, setTempoFactor
always sets the tempo factor to 1.0.
factor
- the requested tempo scalarfloat getTempoFactor()
long getTickLength()
long getTickPosition()
Sequence
.)void setTickPosition(long tick)
tick
- the desired tick positionlong getMicrosecondLength()
long getMicrosecondPosition()
getMicrosecondPosition
in interface MidiDevice
void setMicrosecondPosition(long microseconds)
microseconds
- desired position in microsecondsvoid setMasterSyncMode(Sequencer.SyncMode sync)
sync
. The sync
argument must be one of the supported modes, as returned by getMasterSyncModes()
.sync
- the desired master synchronization modeSequencer.SyncMode getMasterSyncMode()
Sequencer.SyncMode[] getMasterSyncModes()
void setSlaveSyncMode(Sequencer.SyncMode sync)
sync
argument must be one of the supported modes, as returned by getSlaveSyncModes()
.sync
- the desired slave synchronization modeSequencer.SyncMode getSlaveSyncMode()
Sequencer.SyncMode[] getSlaveSyncModes()
void setTrackMute(int track, boolean mute)
getTrackMute(int)
.track
- the track number. Tracks in the current sequence are numbered from 0 to the number of tracks in the sequence minus 1.mute
- the new mute state for the track. true
implies the track should be muted, false
implies the track should be unmuted.boolean getTrackMute(int track)
track
- the track number. Tracks in the current sequence are numbered from 0 to the number of tracks in the sequence minus 1.true
if muted, false
if notvoid setTrackSolo(int track, boolean solo)
solo
is true
only this track and other solo'd tracks will sound. If solo
is false
then only other solo'd tracks will sound, unless no tracks are solo'd in which case all un-muted tracks will sound. This method may fail for a number of reasons. For example, the track number specified may not be valid for the current sequence, or the sequencer may not support this functionality. An application which needs to verify whether this operation succeeded should follow this call with a call to getTrackSolo(int)
.
track
- the track number. Tracks in the current sequence are numbered from 0 to the number of tracks in the sequence minus 1.solo
- the new solo state for the track. true
implies the track should be solo'd, false
implies the track should not be solo'd.boolean getTrackSolo(int track)
track
- the track number. Tracks in the current sequence are numbered from 0 to the number of tracks in the sequence minus 1.true
if solo'd, false
if notboolean addMetaEventListener(MetaEventListener listener)
listener
- listener to addtrue
if the listener was successfully added, otherwise false
void removeMetaEventListener(MetaEventListener listener)
listener
- the meta-event listener to removeint[] addControllerEventListener(ControllerEventListener listener, int[] controllers)
controllers
argument, which should contain an array of MIDI controller numbers. (Each number should be between 0 and 127, inclusive. See the MIDI 1.0 Specification for the numbers that correspond to various types of controllers.) The returned array contains the MIDI controller numbers for which the listener will now receive events. Some sequencers might not support controller event notification, in which case the array has a length of 0. Other sequencers might support notification for some controllers but not all. This method may be invoked repeatedly. Each time, the returned array indicates all the controllers that the listener will be notified about, not only the controllers requested in that particular invocation.
listener
- the controller event listener to add to the list of registered listenerscontrollers
- the MIDI controller numbers for which change notification is requestedint[] removeControllerEventListener(ControllerEventListener listener, int[] controllers)
controllers
argument is an array of MIDI numbers corresponding to the controllers for which the listener should no longer receive change notifications. To completely remove this listener from the list of registered listeners, pass in null
for controllers
. The returned array contains the MIDI controller numbers for which the listener will now receive events. The array has a length of 0 if the listener will not receive change notifications for any controllers.listener
- old listenercontrollers
- the MIDI controller numbers for which change notification should be cancelled, or null
to cancel for all controllersvoid setLoopStartPoint(long tick)
A value of 0 for the starting point means the beginning of the loaded sequence. The starting point must be lower than or equal to the ending point, and it must fall within the size of the loaded sequence.
A sequencer's loop start point defaults to start of the sequence.
tick
- the loop's starting position, in MIDI ticks (zero-based)IllegalArgumentException
- if the requested loop start point cannot be set, usually because it falls outside the sequence's duration or because the start point is after the end pointlong getLoopStartPoint()
void setLoopEndPoint(long tick)
A value of -1 for the ending point indicates the last tick of the sequence. Otherwise, the ending point must be greater than or equal to the starting point, and it must fall within the size of the loaded sequence.
A sequencer's loop end point defaults to -1, meaning the end of the sequence.
tick
- the loop's ending position, in MIDI ticks (zero-based), or -1 to indicate the final tickIllegalArgumentException
- if the requested loop point cannot be set, usually because it falls outside the sequence's duration or because the ending point is before the starting pointlong getLoopEndPoint()
void setLoopCount(int count)
count
times, after which playback will continue to play to the end of the sequence. If the current position when this method is invoked is greater than the loop end point, playback continues to the end of the sequence without looping, unless the loop end point is changed subsequently.
A count
value of 0 disables looping: playback will continue at the loop end point, and it will not loop back to the loop start point. This is a sequencer's default.
If playback is stopped during looping, the current loop status is cleared; subsequent start requests are not affected by an interrupted loop operation.
count
- the number of times playback should loop back from the loop's end position to the loop's start position, or LOOP_CONTINUOUSLY
to indicate that looping should continue until interruptedIllegalArgumentException
- if count
is negative and not equal to LOOP_CONTINUOUSLY
int getLoopCount()
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https://docs.oracle.com/en/java/javase/21/docs/api/java.desktop/javax/sound/midi/Sequencer.html