JetPlayer

public class JetPlayer
extends Object

java.lang.Object
   ↳ android.media.JetPlayer

JetPlayer provides access to JET content playback and control.

Please refer to the JET Creator User Manual for a presentation of the JET interactive music concept and how to use the JetCreator tool to create content to be player by JetPlayer.

Use of the JetPlayer class is based around the playback of a number of JET segments sequentially added to a playback FIFO queue. The rendering of the MIDI content stored in each segment can be dynamically affected by two mechanisms:

  • Tracks in a segment can be muted or unmuted at any moment, individually or through a mask (to change the mute state of multiple tracks at once).
  • Parts of tracks in a segment can be played at predefined points in the segment, in order to maintain synchronization with the other tracks in the segment. This is achieved through the notion of "clips", which can be triggered at any time, but that will play only at the right time, as authored in the corresponding JET file.

As a result of the rendering and playback of the JET segments, the user of the JetPlayer instance can receive notifications from the JET engine relative to:

  • Playback state
  • Number of segments left to play in the queue
  • Application controller events (CC80-83) to mark points in the MIDI segments

Use getJetPlayer() to construct a JetPlayer instance. JetPlayer is a singleton class.

Summary

Nested classes

interface JetPlayer.OnJetEventListener

Handles the notification when the JET engine generates an event. 

Public methods

boolean clearQueue()

Empties the segment queue, and clears all clips that are scheduled for playback.

Object clone()

Cloning a JetPlayer instance is not supported.

boolean closeJetFile()

Closes the resource containing the JET content.

static JetPlayer getJetPlayer()

Factory method for the JetPlayer class.

static int getMaxTracks()

Gets the maximum number of simultaneous MIDI tracks supported by JetPlayer.

boolean loadJetFile(String path)

Loads a .jet file from a given path.

boolean loadJetFile(AssetFileDescriptor afd)

Loads a .jet file from an asset file descriptor.

boolean pause()

Pauses the playback of the JET segment queue.

boolean play()

Starts playing the JET segment queue.

boolean queueJetSegment(int segmentNum, int libNum, int repeatCount, int transpose, int muteFlags, byte userID)

Queues the specified segment in the JET queue.

boolean queueJetSegmentMuteArray(int segmentNum, int libNum, int repeatCount, int transpose, boolean[] muteArray, byte userID)

Queues the specified segment in the JET queue.

void release()

Stops the current JET playback, and releases all associated native resources.

void setEventListener(JetPlayer.OnJetEventListener listener)

Sets the listener JetPlayer notifies when a JET event is generated by the rendering and playback engine.

void setEventListener(JetPlayer.OnJetEventListener listener, Handler handler)

Sets the listener JetPlayer notifies when a JET event is generated by the rendering and playback engine.

boolean setMuteArray(boolean[] muteArray, boolean sync)

Modifies the mute flags for the current active segment.

boolean setMuteFlag(int trackId, boolean muteFlag, boolean sync)

Mutes or unmutes a single track.

boolean setMuteFlags(int muteFlags, boolean sync)

Modifies the mute flags.

boolean triggerClip(int clipId)

Schedules the playback of a clip.

Protected methods

void finalize()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.

Inherited methods

Public methods

clearQueue

Added in API level 3 
public boolean clearQueue ()

Empties the segment queue, and clears all clips that are scheduled for playback.

Returns
boolean true if the queue was successfully cleared, false otherwise.

clone

Added in API level 3 
public Object clone ()

Cloning a JetPlayer instance is not supported. Calling clone() will generate an exception.

Returns
Object a clone of this instance.
Throws
CloneNotSupportedException

closeJetFile

Added in API level 3 
public boolean closeJetFile ()

Closes the resource containing the JET content.

Returns
boolean true if successfully closed, false otherwise.

getJetPlayer

Added in API level 3 
public static JetPlayer getJetPlayer ()

Factory method for the JetPlayer class.

Returns
JetPlayer the singleton JetPlayer instance.

getMaxTracks

Added in API level 3 
public static int getMaxTracks ()

Gets the maximum number of simultaneous MIDI tracks supported by JetPlayer.

Returns
int the maximum number of simultaneous MIDI tracks supported by JetPlayer.

loadJetFile

Added in API level 3 
public boolean loadJetFile (String path)

Loads a .jet file from a given path.

Parameters
path String: the path to the .jet file, for instance "/sdcard/mygame/music.jet".
Returns
boolean true if loading the .jet file was successful, false if loading failed.

loadJetFile

Added in API level 3 
public boolean loadJetFile (AssetFileDescriptor afd)

Loads a .jet file from an asset file descriptor.

Parameters
afd AssetFileDescriptor: the asset file descriptor.
Returns
boolean true if loading the .jet file was successful, false if loading failed.

pause

Added in API level 3 
public boolean pause ()

Pauses the playback of the JET segment queue.

Returns
boolean true if rendering and playback is successfully paused, false otherwise.

play

Added in API level 3 
public boolean play ()

Starts playing the JET segment queue.

Returns
boolean true if rendering and playback is successfully started, false otherwise.

queueJetSegment

Added in API level 3 
public boolean queueJetSegment (int segmentNum, 
                int libNum, 
                int repeatCount, 
                int transpose, 
                int muteFlags, 
                byte userID)

Queues the specified segment in the JET queue.

Parameters
segmentNum int: the identifier of the segment.
libNum int: the index of the sound bank associated with the segment. Use -1 to indicate that no sound bank (DLS file) is associated with this segment, in which case JET will use the General MIDI library.
repeatCount int: the number of times the segment will be repeated. 0 means the segment will only play once. -1 means the segment will repeat indefinitely.
transpose int: the amount of pitch transposition. Set to 0 for normal playback. Range is -12 to +12.
muteFlags int: a bitmask to specify which MIDI tracks will be muted during playback. Bit 0 affects track 0, bit 1 affects track 1 etc.
userID byte: a value specified by the application that uniquely identifies the segment. this value is received in the OnJetEventListener#onJetUserIdUpdate(JetPlayer, int, int) event listener method. Normally, the application will keep a byte value that is incremented each time a new segment is queued up. This can be used to look up any special characteristics of that track including trigger clips and mute flags.
Returns
boolean true if the segment was successfully queued, false if the queue is full or if the parameters are invalid.

queueJetSegmentMuteArray

Added in API level 3 
public boolean queueJetSegmentMuteArray (int segmentNum, 
                int libNum, 
                int repeatCount, 
                int transpose, 
                boolean[] muteArray, 
                byte userID)

Queues the specified segment in the JET queue.

Parameters
segmentNum int: the identifier of the segment.
libNum int: the index of the soundbank associated with the segment. Use -1 to indicate that no sound bank (DLS file) is associated with this segment, in which case JET will use the General MIDI library.
repeatCount int: the number of times the segment will be repeated. 0 means the segment will only play once. -1 means the segment will repeat indefinitely.
transpose int: the amount of pitch transposition. Set to 0 for normal playback. Range is -12 to +12.
muteArray boolean: an array of booleans to specify which MIDI tracks will be muted during playback. The value at index 0 affects track 0, value at index 1 affects track 1 etc. The length of the array must be getMaxTracks() for the call to succeed.
userID byte: a value specified by the application that uniquely identifies the segment. this value is received in the OnJetEventListener#onJetUserIdUpdate(JetPlayer, int, int) event listener method. Normally, the application will keep a byte value that is incremented each time a new segment is queued up. This can be used to look up any special characteristics of that track including trigger clips and mute flags.
Returns
boolean true if the segment was successfully queued, false if the queue is full or if the parameters are invalid.

release

Added in API level 3 
public void release ()

Stops the current JET playback, and releases all associated native resources. The object can no longer be used and the reference should be set to null after a call to release().

setEventListener

Added in API level 3 
public void setEventListener (JetPlayer.OnJetEventListener listener)

Sets the listener JetPlayer notifies when a JET event is generated by the rendering and playback engine. Notifications are received in the same thread as the one in which the JetPlayer instance was created.

Parameters
listener JetPlayer.OnJetEventListener: the listener that will be notified when a JET event is generated.

setEventListener

Added in API level 3 
public void setEventListener (JetPlayer.OnJetEventListener listener, 
                Handler handler)

Sets the listener JetPlayer notifies when a JET event is generated by the rendering and playback engine. Use this method to receive JET events in the Handler associated with another thread than the one in which you created the JetPlayer instance.

Parameters
listener JetPlayer.OnJetEventListener: the listener that will be notified when a JET event is generated.
handler Handler: the Handler that will receive the event notification messages.

setMuteArray

Added in API level 3 
public boolean setMuteArray (boolean[] muteArray, 
                boolean sync)

Modifies the mute flags for the current active segment.

Parameters
muteArray boolean: an array of booleans to specify which MIDI tracks are muted. The value at index 0 affects track 0, value at index 1 affects track 1 etc. The length of the array must be getMaxTracks() for the call to succeed.
sync boolean: if false, the new mute flags will be applied as soon as possible by the JET render and playback engine. If true, the mute flags will be updated at the start of the next segment. If the segment is repeated, the flags will take effect the next time segment is repeated.
Returns
boolean true if the mute flags were successfully updated, false otherwise.

setMuteFlag

Added in API level 3 
public boolean setMuteFlag (int trackId, 
                boolean muteFlag, 
                boolean sync)

Mutes or unmutes a single track.

Parameters
trackId int: the index of the track to mute.
muteFlag boolean: set to true to mute, false to unmute.
sync boolean: if false, the new mute flags will be applied as soon as possible by the JET render and playback engine. If true, the mute flag will be updated at the start of the next segment. If the segment is repeated, the flag will take effect the next time segment is repeated.
Returns
boolean true if the mute flag was successfully updated, false otherwise.

setMuteFlags

Added in API level 3 
public boolean setMuteFlags (int muteFlags, 
                boolean sync)

Modifies the mute flags.

Parameters
muteFlags int: a bitmask to specify which MIDI tracks are muted. Bit 0 affects track 0, bit 1 affects track 1 etc.
sync boolean: if false, the new mute flags will be applied as soon as possible by the JET render and playback engine. If true, the mute flags will be updated at the start of the next segment. If the segment is repeated, the flags will take effect the next time segment is repeated.
Returns
boolean true if the mute flags were successfully updated, false otherwise.

triggerClip

Added in API level 3 
public boolean triggerClip (int clipId)

Schedules the playback of a clip. This will automatically update the mute flags in sync with the JET Clip Marker (controller 103). The parameter clipID must be in the range of 0-63. After the call to triggerClip, when JET next encounters a controller event 103 with bits 0-5 of the value equal to clipID and bit 6 set to 1, it will automatically unmute the track containing the controller event. When JET encounters the complementary controller event 103 with bits 0-5 of the value equal to clipID and bit 6 set to 0, it will mute the track again.

Parameters
clipId int: the identifier of the clip to trigger.
Returns
boolean true if the clip was successfully triggered, false otherwise.

Protected methods

finalize

Added in API level 3 
protected void finalize ()

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. A subclass overrides the finalize method to dispose of system resources or to perform other cleanup.

The general contract of finalize is that it is invoked if and when the Java virtual machine has determined that there is no longer any means by which this object can be accessed by any thread that has not yet died, except as a result of an action taken by the finalization of some other object or class which is ready to be finalized. The finalize method may take any action, including making this object available again to other threads; the usual purpose of finalize, however, is to perform cleanup actions before the object is irrevocably discarded. For example, the finalize method for an object that represents an input/output connection might perform explicit I/O transactions to break the connection before the object is permanently discarded.

The finalize method of class Object performs no special action; it simply returns normally. Subclasses of Object may override this definition.

The Java programming language does not guarantee which thread will invoke the finalize method for any given object. It is guaranteed, however, that the thread that invokes finalize will not be holding any user-visible synchronization locks when finalize is invoked. If an uncaught exception is thrown by the finalize method, the exception is ignored and finalization of that object terminates.

After the finalize method has been invoked for an object, no further action is taken until the Java virtual machine has again determined that there is no longer any means by which this object can be accessed by any thread that has not yet died, including possible actions by other objects or classes which are ready to be finalized, at which point the object may be discarded.

The finalize method is never invoked more than once by a Java virtual machine for any given object.

Any exception thrown by the finalize method causes the finalization of this object to be halted, but is otherwise ignored.