Track (Java Platform SE 8 )
Keywords: javax.sound.midi.Track class
Date: 2015-05-24

javax.sound.midi

## Class Track

- java.lang.Object
- - javax.sound.midi.Track

-     public class Track
      extends Object

  A MIDI track is an independent stream of MIDI events (time-stamped MIDI data) that can be stored along with other tracks in a standard MIDI file. The MIDI specification allows only 16 channels of MIDI data, but tracks are a way to get around this limitation. A MIDI file can contain any number of tracks, each containing its own stream of up to 16 channels of MIDI data.

  A `Track` occupies a middle level in the hierarchy of data played by a ``Sequencer``: sequencers play sequences, which contain tracks, which contain MIDI events. A sequencer may provide controls that mute or solo individual tracks.

  The timing information and resolution for a track is controlled by and stored in the sequence containing the track. A given `Track` is considered to belong to the particular ``Sequence`` that maintains its timing. For this reason, a new (empty) track is created by calling the ``Sequence.createTrack()`` method, rather than by directly invoking a `Track` constructor.

  The `Track` class provides methods to edit the track by adding or removing `MidiEvent` objects from it. These operations keep the event list in the correct time order. Methods are also included to obtain the track's size, in terms of either the number of events it contains or its duration in ticks.

  See Also:
    `Sequencer.setTrackMute(int, boolean)`, `Sequencer.setTrackSolo(int, boolean)`

- - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `boolean` | `add(MidiEvent event)` Adds a new event to the track.
    `MidiEvent` | `get(int index)` Obtains the event at the specified index.
    `boolean` | `remove(MidiEvent event)` Removes the specified event from the track.
    `int` | `size()` Obtains the number of events in this track.
    `long` | `ticks()` Obtains the length of the track, expressed in MIDI ticks.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Method Detail

    - #### add

          public boolean add(MidiEvent event)

      Adds a new event to the track. However, if the event is already contained in the track, it is not added again. The list of events is kept in time order, meaning that this event inserted at the appropriate place in the list, not necessarily at the end.
      Parameters:
        `event` - the event to add
      Returns:
        `true` if the event did not already exist in the track and was added, otherwise `false`

    - #### remove

          public boolean remove(MidiEvent event)

      Removes the specified event from the track.
      Parameters:
        `event` - the event to remove
      Returns:
        `true` if the event existed in the track and was removed, otherwise `false`

    - #### get

          public MidiEvent get(int index)
                        throws ArrayIndexOutOfBoundsException

      Obtains the event at the specified index.
      Parameters:
        `index` - the location of the desired event in the event vector
      Returns:
        the event at the specified index
      Throws:
        `ArrayIndexOutOfBoundsException` - if the specified index is negative or not less than the current size of this track.
      See Also:
        `size()`

    - #### size

          public int size()

      Obtains the number of events in this track.
      Returns:
        the size of the track's event vector

    - #### ticks

          public long ticks()

      Obtains the length of the track, expressed in MIDI ticks. (The duration of a tick in seconds is determined by the timing resolution of the `Sequence` containing this track, and also by the tempo of the music as set by the sequencer.)
      Returns:
        the duration, in ticks
      See Also:
        `Sequence.Sequence(float, int)`, `Sequencer.setTempoInBPM(float)`, `Sequencer.getTickPosition()`

Submit a bug or feature
For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
Copyright © 1993, 2015, Oracle and/or its affiliates. All rights reserved.