public class VoiceStatus extends Object
VoiceStatusobject contains information about the current status of one of the voices produced by a
MIDI synthesizers are generally capable of producing some maximum number of simultaneous notes, also referred to as voices. A voice is a stream of successive single notes, and the process of assigning incoming MIDI notes to specific voices is known as voice allocation. However, the voice-allocation algorithm and the contents of each voice are normally internal to a MIDI synthesizer and hidden from outside view. One can, of course, learn from MIDI messages which notes the synthesizer is playing, and one might be able deduce something about the assignment of notes to voices. But MIDI itself does not provide a means to report which notes a synthesizer has assigned to which voice, nor even to report how many voices the synthesizer is capable of synthesizing.
In Java Sound, however, a
Synthesizer class can expose the contents of its voices through its
This behavior is recommended but optional;
synthesizers that don't expose their voice allocation simply return a
zero-length array. A
Synthesizer that does report its voice status
should maintain this information at
all times for all of its voices, whether they are currently sounding or
not. In other words, a given type of
Synthesizer always has a fixed
number of voices, equal to the maximum number of simultaneous notes it is
capable of sounding.
If the voice is not currently processing a MIDI note, it is considered inactive. A voice is inactive when it has been given no note-on commands, or when every note-on command received has been terminated by a corresponding note-off (or by an "all notes off" message). For example, this happens when a synthesizer capable of playing 16 simultaneous notes is told to play a four-note chord; only four voices are active in this case (assuming no earlier notes are still playing). Usually, a voice whose status is reported as active is producing audible sound, but this is not always true; it depends on the details of the instrument (that is, the synthesis algorithm) and how long the note has been going on. For example, a voice may be synthesizing the sound of a single hand-clap. Because this sound dies away so quickly, it may become inaudible before a note-off message is received. In such a situation, the voice is still considered active even though no sound is currently being produced.
Besides its active or inactive status, the
provides fields that reveal the voice's current MIDI channel, bank and
program number, MIDI note number, and MIDI volume. All of these can
change during the course of a voice. While the voice is inactive, each
of these fields has an unspecified value, so you should check the active
|Modifier and Type||Field and Description|
Indicates whether the voice is currently processing a MIDI note.
The bank number of the instrument that this voice is currently using.
The MIDI channel on which this voice is playing.
The MIDI note that this voice is playing.
The program number of the instrument that this voice is currently using.
The current MIDI volume level for the voice.
|Constructor and Description|
public boolean active
public int channel
public int bank
SoundBankobject. The value ranges from 0 to 16383 if the voice is active, and is unspecified if the voice is inactive.
public int program
public int note
public int volume
Note that this value does not necessarily reflect the instantaneous level of the sound produced by this voice; that level is the result of many contributing factors, including the current instrument and the shape of the amplitude envelope it produces.