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	/*
	* Copyright (c) 1998, 2004, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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	package javax.sound.midi;


	/**
	* A <code>MidiChannel</code> object represents a single MIDI channel.
	* Generally, each <code>MidiChannel</code> method processes a like-named MIDI
	* "channel voice" or "channel mode" message as defined by the MIDI specification. However,
	* <code>MidiChannel</code> adds some "get" methods that retrieve the value
	* most recently set by one of the standard MIDI channel messages. Similarly,
	* methods for per-channel solo and mute have been added.
	* <p>
	* A <code>{@link Synthesizer}</code> object has a collection
	* of <code>MidiChannels</code>, usually one for each of the 16 channels
	* prescribed by the MIDI 1.0 specification. The <code>Synthesizer</code>
	* generates sound when its <code>MidiChannels</code> receive
	* <code>noteOn</code> messages.
	* <p>
	* See the MIDI 1.0 Specification for more information about the prescribed
	* behavior of the MIDI channel messages, which are not exhaustively
	* documented here. The specification is titled <code>MIDI Reference:
	* The Complete MIDI 1.0 Detailed Specification</code>, and is published by
	* the MIDI Manufacturer's Association (<a href = http://www.midi.org>
	* http://www.midi.org</a>).
	* <p>
	* MIDI was originally a protocol for reporting the gestures of a keyboard
	* musician. This genesis is visible in the <code>MidiChannel</code> API, which
	* preserves such MIDI concepts as key number, key velocity, and key pressure.
	* It should be understood that the MIDI data does not necessarily originate
	* with a keyboard player (the source could be a different kind of musician, or
	* software). Some devices might generate constant values for velocity
	* and pressure, regardless of how the note was performed.
	* Also, the MIDI specification often leaves it up to the
	* synthesizer to use the data in the way the implementor sees fit. For
	* example, velocity data need not always be mapped to volume and/or brightness.
	*
	* @see Synthesizer#getChannels
	*
	* @author David Rivas
	* @author Kara Kytle
	*/

	public interface MidiChannel {

	/**
	* Starts the specified note sounding. The key-down velocity
	* usually controls the note's volume and/or brightness.
	* If <code>velocity</code> is zero, this method instead acts like
	* {@link #noteOff(int)}, terminating the note.
	*
	* @param noteNumber the MIDI note number, from 0 to 127 (60 = Middle C)
	* @param velocity the speed with which the key was depressed
	*
	* @see #noteOff(int, int)
	*/
	public void noteOn(int noteNumber, int velocity);

	/**
	* Turns the specified note off. The key-up velocity, if not ignored, can
	* be used to affect how quickly the note decays.
	* In any case, the note might not die away instantaneously; its decay
	* rate is determined by the internals of the <code>Instrument</code>.
	* If the Hold Pedal (a controller; see
	* {@link #controlChange(int, int) controlChange})
	* is down, the effect of this method is deferred until the pedal is
	* released.
	*
	*
	* @param noteNumber the MIDI note number, from 0 to 127 (60 = Middle C)
	* @param velocity the speed with which the key was released
	*
	* @see #noteOff(int)
	* @see #noteOn
	* @see #allNotesOff
	* @see #allSoundOff
	*/
	public void noteOff(int noteNumber, int velocity);

	/**
	* Turns the specified note off.
	*
	* @param noteNumber the MIDI note number, from 0 to 127 (60 = Middle C)
	*
	* @see #noteOff(int, int)
	*/
	public void noteOff(int noteNumber);

	/**
	* Reacts to a change in the specified note's key pressure.
	* Polyphonic key pressure
	* allows a keyboard player to press multiple keys simultaneously, each
	* with a different amount of pressure. The pressure, if not ignored,
	* is typically used to vary such features as the volume, brightness,
	* or vibrato of the note.
	*
	* It is possible that the underlying synthesizer
	* does not support this MIDI message. In order
	* to verify that <code>setPolyPressure</code>
	* was successful, use <code>getPolyPressure</code>.
	*
	* @param noteNumber the MIDI note number, from 0 to 127 (60 = Middle C)
	* @param pressure value for the specified key, from 0 to 127 (127 =
	* maximum pressure)
	*
	* @see #getPolyPressure(int)
	*/
	public void setPolyPressure(int noteNumber, int pressure);

	/**
	* Obtains the pressure with which the specified key is being depressed.
	*
	* @param noteNumber the MIDI note number, from 0 to 127 (60 = Middle C)
	*
	* If the device does not support setting poly pressure,
	* this method always returns 0. Calling
	* <code>setPolyPressure</code> will have no effect then.
	*
	* @return the amount of pressure for that note, from 0 to 127
	* (127 = maximum pressure)
	*
	* @see #setPolyPressure(int, int)
	*/
	public int getPolyPressure(int noteNumber);

	/**
	* Reacts to a change in the keyboard pressure. Channel
	* pressure indicates how hard the keyboard player is depressing
	* the entire keyboard. This can be the maximum or
	* average of the per-key pressure-sensor values, as set by
	* <code>setPolyPressure</code>. More commonly, it is a measurement of
	* a single sensor on a device that doesn't implement polyphonic key
	* pressure. Pressure can be used to control various aspects of the sound,
	* as described under {@link #setPolyPressure(int, int) setPolyPressure}.
	*
	* It is possible that the underlying synthesizer
	* does not support this MIDI message. In order
	* to verify that <code>setChannelPressure</code>
	* was successful, use <code>getChannelPressure</code>.
	*
	* @param pressure the pressure with which the keyboard is being depressed,
	* from 0 to 127 (127 = maximum pressure)
	* @see #setPolyPressure(int, int)
	* @see #getChannelPressure
	*/
	public void setChannelPressure(int pressure);

	/**
	* Obtains the channel's keyboard pressure.
	* If the device does not support setting channel pressure,
	* this method always returns 0. Calling
	* <code>setChannelPressure</code> will have no effect then.
	*
	* @return the amount of pressure for that note,
	* from 0 to 127 (127 = maximum pressure)
	*
	* @see #setChannelPressure(int)
	*/
	public int getChannelPressure();

	/**
	* Reacts to a change in the specified controller's value. A controller
	* is some control other than a keyboard key, such as a
	* switch, slider, pedal, wheel, or breath-pressure sensor.
	* The MIDI 1.0 Specification provides standard numbers for typical
	* controllers on MIDI devices, and describes the intended effect
	* for some of the controllers.
	* The way in which an
	* <code>Instrument</code> reacts to a controller change may be
	* specific to the <code>Instrument</code>.
	* <p>
	* The MIDI 1.0 Specification defines both 7-bit controllers
	* and 14-bit controllers. Continuous controllers, such
	* as wheels and sliders, typically have 14 bits (two MIDI bytes),
	* while discrete controllers, such as switches, typically have 7 bits
	* (one MIDI byte). Refer to the specification to see the
	* expected resolution for each type of control.
	* <p>
	* Controllers 64 through 95 (0x40 - 0x5F) allow 7-bit precision.
	* The value of a 7-bit controller is set completely by the
	* <code>value</code> argument. An additional set of controllers
	* provide 14-bit precision by using two controller numbers, one
	* for the most significant 7 bits and another for the least significant
	* 7 bits. Controller numbers 0 through 31 (0x00 - 0x1F) control the
	* most significant 7 bits of 14-bit controllers; controller numbers
	* 32 through 63 (0x20 - 0x3F) control the least significant 7 bits of
	* these controllers. For example, controller number 7 (0x07) controls
	* the upper 7 bits of the channel volume controller, and controller
	* number 39 (0x27) controls the lower 7 bits.
	* The value of a 14-bit controller is determined
	* by the interaction of the two halves. When the most significant 7 bits
	* of a controller are set (using controller numbers 0 through 31), the
	* lower 7 bits are automatically set to 0. The corresponding controller
	* number for the lower 7 bits may then be used to further modulate the
	* controller value.
	*
	* It is possible that the underlying synthesizer
	* does not support a specific controller message. In order
	* to verify that a call to <code>controlChange</code>
	* was successful, use <code>getController</code>.
	*
	* @param controller the controller number (0 to 127; see the MIDI
	* 1.0 Specification for the interpretation)
	* @param value the value to which the specified controller is changed (0 to 127)
	*
	* @see #getController(int)
	*/
	public void controlChange(int controller, int value);

	/**
	* Obtains the current value of the specified controller. The return
	* value is represented with 7 bits. For 14-bit controllers, the MSB and
	* LSB controller value needs to be obtained separately. For example,
	* the 14-bit value of the volume controller can be calculated by
	* multiplying the value of controller 7 (0x07, channel volume MSB)
	* with 128 and adding the
	* value of controller 39 (0x27, channel volume LSB).
	*
	* If the device does not support setting a specific controller,
	* this method returns 0 for that controller.
	* Calling <code>controlChange</code> will have no effect then.
	*
	* @param controller the number of the controller whose value is desired.
	* The allowed range is 0-127; see the MIDI
	* 1.0 Specification for the interpretation.
	*
	* @return the current value of the specified controller (0 to 127)
	*
	* @see #controlChange(int, int)
	*/
	public int getController(int controller);

	/**
	* Changes a program (patch). This selects a specific
	* instrument from the currently selected bank of instruments.
	* <p>
	* The MIDI specification does not
	* dictate whether notes that are already sounding should switch
	* to the new instrument (timbre) or continue with their original timbre
	* until terminated by a note-off.
	* <p>
	* The program number is zero-based (expressed from 0 to 127).
	* Note that MIDI hardware displays and literature about MIDI
	* typically use the range 1 to 128 instead.
	*
	* It is possible that the underlying synthesizer
	* does not support a specific program. In order
	* to verify that a call to <code>programChange</code>
	* was successful, use <code>getProgram</code>.
	*
	* @param program the program number to switch to (0 to 127)
	*
	* @see #programChange(int, int)
	* @see #getProgram()
	*/
	public void programChange(int program);

	/**
	* Changes the program using bank and program (patch) numbers.
	*
	* It is possible that the underlying synthesizer
	* does not support a specific bank, or program. In order
	* to verify that a call to <code>programChange</code>
	* was successful, use <code>getProgram</code> and
	* <code>getController</code>.
	* Since banks are changed by way of control changes,
	* you can verify the current bank with the following
	* statement:
	* <pre>
	* int bank = (getController(0) * 128)
	* + getController(32);
	* </pre>
	*
	* @param bank the bank number to switch to (0 to 16383)
	* @param program the program (patch) to use in the specified bank (0 to 127)
	* @see #programChange(int)
	* @see #getProgram()
	*/
	public void programChange(int bank, int program);

	/**
	* Obtains the current program number for this channel.
	* @return the program number of the currently selected patch
	* @see Patch#getProgram
	* @see Synthesizer#loadInstrument
	* @see #programChange(int)
	*/
	public int getProgram();

	/**
	* Changes the pitch offset for all notes on this channel.
	* This affects all currently sounding notes as well as subsequent ones.
	* (For pitch bend to cease, the value needs to be reset to the
	* center position.)
	* <p> The MIDI specification
	* stipulates that pitch bend be a 14-bit value, where zero
	* is maximum downward bend, 16383 is maximum upward bend, and
	* 8192 is the center (no pitch bend). The actual
	* amount of pitch change is not specified; it can be changed by
	* a pitch-bend sensitivity setting. However, the General MIDI
	* specification says that the default range should be two semitones
	* up and down from center.
	*
	* It is possible that the underlying synthesizer
	* does not support this MIDI message. In order
	* to verify that <code>setPitchBend</code>
	* was successful, use <code>getPitchBend</code>.
	*
	* @param bend the amount of pitch change, as a nonnegative 14-bit value
	* (8192 = no bend)
	*
	* @see #getPitchBend
	*/
	public void setPitchBend(int bend);

	/**
	* Obtains the upward or downward pitch offset for this channel.
	* If the device does not support setting pitch bend,
	* this method always returns 8192. Calling
	* <code>setPitchBend</code> will have no effect then.
	*
	* @return bend amount, as a nonnegative 14-bit value (8192 = no bend)
	*
	* @see #setPitchBend(int)
	*/
	public int getPitchBend();

	/**
	* Resets all the implemented controllers to their default values.
	*
	* @see #controlChange(int, int)
	*/
	public void resetAllControllers();

	/**
	* Turns off all notes that are currently sounding on this channel.
	* The notes might not die away instantaneously; their decay
	* rate is determined by the internals of the <code>Instrument</code>.
	* If the Hold Pedal controller (see
	* {@link #controlChange(int, int) controlChange})
	* is down, the effect of this method is deferred until the pedal is
	* released.
	*
	* @see #allSoundOff
	* @see #noteOff(int)
	*/
	public void allNotesOff();

	/**
	* Immediately turns off all sounding notes on this channel, ignoring the
	* state of the Hold Pedal and the internal decay rate of the current
	* <code>Instrument</code>.
	*
	* @see #allNotesOff
	*/
	public void allSoundOff();

	/**
	* Turns local control on or off. The default is for local control
	* to be on. The "on" setting means that if a device is capable
	* of both synthesizing sound and transmitting MIDI messages,
	* it will synthesize sound in response to the note-on and
	* note-off messages that it itself transmits. It will also respond
	* to messages received from other transmitting devices.
	* The "off" setting means that the synthesizer will ignore its
	* own transmitted MIDI messages, but not those received from other devices.
	*
	* It is possible that the underlying synthesizer
	* does not support local control. In order
	* to verify that a call to <code>localControl</code>
	* was successful, check the return value.
	*
	* @param on <code>true</code> to turn local control on, <code>false</code>
	* to turn local control off
	* @return the new local-control value, or false
	* if local control is not supported
	*
	*/
	public boolean localControl(boolean on);

	/**
	* Turns mono mode on or off. In mono mode, the channel synthesizes
	* only one note at a time. In poly mode (identical to mono mode off),
	* the channel can synthesize multiple notes simultaneously.
	* The default is mono off (poly mode on).
	* <p>
	* "Mono" is short for the word "monophonic," which in this context
	* is opposed to the word "polyphonic" and refers to a single synthesizer
	* voice per MIDI channel. It
	* has nothing to do with how many audio channels there might be
	* (as in "monophonic" versus "stereophonic" recordings).
	*
	* It is possible that the underlying synthesizer
	* does not support mono mode. In order
	* to verify that a call to <code>setMono</code>
	* was successful, use <code>getMono</code>.
	*
	* @param on <code>true</code> to turn mono mode on, <code>false</code> to
	* turn it off (which means turning poly mode on).
	*
	* @see #getMono
	* @see VoiceStatus
	*/
	public void setMono(boolean on);

	/**
	* Obtains the current mono/poly mode.
	* Synthesizers that do not allow changing mono/poly mode
	* will always return the same value, regardless
	* of calls to <code>setMono</code>.
	* @return <code>true</code> if mono mode is on, otherwise
	* <code>false</code> (meaning poly mode is on).
	*
	* @see #setMono(boolean)
	*/
	public boolean getMono();

	/**
	* Turns omni mode on or off. In omni mode, the channel responds
	* to messages sent on all channels. When omni is off, the channel
	* responds only to messages sent on its channel number.
	* The default is omni off.
	*
	* It is possible that the underlying synthesizer
	* does not support omni mode. In order
	* to verify that <code>setOmni</code>
	* was successful, use <code>getOmni</code>.
	*
	* @param on <code>true</code> to turn omni mode on, <code>false</code> to
	* turn it off.
	*
	* @see #getOmni
	* @see VoiceStatus
	*/
	public void setOmni(boolean on);

	/**
	* Obtains the current omni mode.
	* Synthesizers that do not allow changing the omni mode
	* will always return the same value, regardless
	* of calls to <code>setOmni</code>.
	* @return <code>true</code> if omni mode is on, otherwise
	* <code>false</code> (meaning omni mode is off).
	*
	* @see #setOmni(boolean)
	*/
	public boolean getOmni();

	/**
	* Sets the mute state for this channel. A value of
	* <code>true</code> means the channel is to be muted, <code>false</code>
	* means the channel can sound (if other channels are not soloed).
	* <p>
	* Unlike {@link #allSoundOff()}, this method
	* applies to only a specific channel, not to all channels. Further, it
	* silences not only currently sounding notes, but also subsequently
	* received notes.
	*
	* It is possible that the underlying synthesizer
	* does not support muting channels. In order
	* to verify that a call to <code>setMute</code>
	* was successful, use <code>getMute</code>.
	*
	* @param mute the new mute state
	*
	* @see #getMute
	* @see #setSolo(boolean)
	*/
	public void setMute(boolean mute);

	/**
	* Obtains the current mute state for this channel.
	* If the underlying synthesizer does not support
	* muting this channel, this method always returns
	* <code>false</code>.
	*
	* @return <code>true</code> the channel is muted,
	* or <code>false</code> if not
	*
	* @see #setMute(boolean)
	*/
	public boolean getMute();

	/**
	* Sets the solo state for this channel.
	* If <code>solo</code> is <code>true</code> only this channel
	* and other soloed channels will sound. If <code>solo</code>
	* is <code>false</code> then only other soloed channels will
	* sound, unless no channels are soloed, in which case all
	* unmuted channels will sound.
	*
	* It is possible that the underlying synthesizer
	* does not support solo channels. In order
	* to verify that a call to <code>setSolo</code>
	* was successful, use <code>getSolo</code>.
	*
	* @param soloState new solo state for the channel
	* @see #getSolo()
	*/
	public void setSolo(boolean soloState);

	/**
	* Obtains the current solo state for this channel.
	* If the underlying synthesizer does not support
	* solo on this channel, this method always returns
	* <code>false</code>.
	*
	* @return <code>true</code> the channel is solo,
	* or <code>false</code> if not
	*
	* @see #setSolo(boolean)
	*/
	public boolean getSolo();
	}

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