java.lang.Object
javax.sound.sampled.Control
javax.sound.sampled.FloatControl
A
FloatControl
object provides control over a range of floating-point
values. Float controls are often represented in graphical user interfaces by
continuously adjustable objects such as sliders or rotary knobs. Concrete
subclasses of FloatControl
implement controls, such as gain and pan,
that affect a line's audio signal in some way that an application can
manipulate. The FloatControl.Type
inner class provides static
instances of types that are used to identify some common kinds of float
control.
The FloatControl
abstract class provides methods to set and get the
control's current floating-point value. Other methods obtain the possible
range of values and the control's resolution (the smallest increment between
returned values). Some float controls allow ramping to a new value over a
specified period of time. FloatControl
also includes methods that
return string labels for the minimum, maximum, and midpoint positions of the
control.
- Since:
- 1.3
- See Also:
-
Nested Class Summary
Modifier and TypeClassDescriptionstatic class
An instance of theFloatControl.Type
inner class identifies one kind of float control. -
Constructor Summary
ModifierConstructorDescriptionprotected
FloatControl
(FloatControl.Type type, float minimum, float maximum, float precision, int updatePeriod, float initialValue, String units) Constructs a new float control object with the given parameters.protected
FloatControl
(FloatControl.Type type, float minimum, float maximum, float precision, int updatePeriod, float initialValue, String units, String minLabel, String midLabel, String maxLabel) Constructs a new float control object with the given parameters. -
Method Summary
Modifier and TypeMethodDescriptionfloat
Obtains the maximum value permitted.Obtains the label for the maximum value, such as "Right" or "Full".Obtains the label for the mid-point value, such as "Center" or "Default".float
Obtains the minimum value permitted.Obtains the label for the minimum value, such as "Left" or "Off".float
Obtains the resolution or granularity of the control, in the units that the control measures.getUnits()
Obtains the label for the units in which the control's values are expressed, such as "dB" or "frames per second."int
Obtains the smallest time interval, in microseconds, over which the control's value can change during a shift.float
getValue()
Obtains this control's current value.void
setValue
(float newValue) Sets the current value for the control.void
shift
(float from, float to, int microseconds) Changes the control value from the initial value to the final value linearly over the specified time period, specified in microseconds.toString()
Returns a string representation of the float control.
-
Constructor Details
-
FloatControl
protected FloatControl(FloatControl.Type type, float minimum, float maximum, float precision, int updatePeriod, float initialValue, String units, String minLabel, String midLabel, String maxLabel) Constructs a new float control object with the given parameters.- Parameters:
type
- the kind of control represented by this float control objectminimum
- the smallest value permitted for the controlmaximum
- the largest value permitted for the controlprecision
- the resolution or granularity of the control. This is the size of the increment between discrete valid values.updatePeriod
- the smallest time interval, in microseconds, over which the control can change from one discrete value to the next during ashift
initialValue
- the value that the control starts with when constructedunits
- the label for the units in which the control's values are expressed, such as "dB" or "frames per second"minLabel
- the label for the minimum value, such as "Left" or "Off"midLabel
- the label for the midpoint value, such as "Center" or "Default"maxLabel
- the label for the maximum value, such as "Right" or "Full"- Throws:
IllegalArgumentException
- ifminimum
is greater thanmaximum
orinitialValue
does not fall within the allowable range
-
FloatControl
protected FloatControl(FloatControl.Type type, float minimum, float maximum, float precision, int updatePeriod, float initialValue, String units) Constructs a new float control object with the given parameters. The labels for the minimum, maximum, and mid-point values are set to zero-length strings.- Parameters:
type
- the kind of control represented by this float control objectminimum
- the smallest value permitted for the controlmaximum
- the largest value permitted for the controlprecision
- the resolution or granularity of the control. This is the size of the increment between discrete valid values.updatePeriod
- the smallest time interval, in microseconds, over which the control can change from one discrete value to the next during ashift
initialValue
- the value that the control starts with when constructedunits
- the label for the units in which the control's values are expressed, such as "dB" or "frames per second"- Throws:
IllegalArgumentException
- ifminimum
is greater thanmaximum
orinitialValue
does not fall within the allowable range
-
-
Method Details
-
setValue
public void setValue(float newValue) Sets the current value for the control. The default implementation simply sets the value as indicated. If the value indicated is greater than the maximum value, or smaller than the minimum value, anIllegalArgumentException
is thrown. Some controls require that their line be open before they can be affected by setting a value.- Parameters:
newValue
- desired new value- Throws:
IllegalArgumentException
- if the value indicated does not fall within the allowable range
-
getValue
public float getValue()Obtains this control's current value.- Returns:
- the current value
-
getMaximum
public float getMaximum()Obtains the maximum value permitted.- Returns:
- the maximum allowable value
-
getMinimum
public float getMinimum()Obtains the minimum value permitted.- Returns:
- the minimum allowable value
-
getUnits
Obtains the label for the units in which the control's values are expressed, such as "dB" or "frames per second."- Returns:
- the units label, or a zero-length string if no label
-
getMinLabel
Obtains the label for the minimum value, such as "Left" or "Off".- Returns:
- the minimum value label, or a zero-length string if no label has been set
-
getMidLabel
Obtains the label for the mid-point value, such as "Center" or "Default".- Returns:
- the mid-point value label, or a zero-length string if no label has been set
-
getMaxLabel
Obtains the label for the maximum value, such as "Right" or "Full".- Returns:
- the maximum value label, or a zero-length string if no label has been set
-
getPrecision
public float getPrecision()Obtains the resolution or granularity of the control, in the units that the control measures. The precision is the size of the increment between discrete valid values for this control, over the set of supported floating-point values.- Returns:
- the control's precision
-
getUpdatePeriod
public int getUpdatePeriod()Obtains the smallest time interval, in microseconds, over which the control's value can change during a shift. The update period is the inverse of the frequency with which the control updates its value during a shift. If the implementation does not support value shifting over time, it should set the control's value to the final value immediately and return -1 from this method.- Returns:
- update period in microseconds, or -1 if shifting over time is unsupported
- See Also:
-
shift
public void shift(float from, float to, int microseconds) Changes the control value from the initial value to the final value linearly over the specified time period, specified in microseconds. This method returns without blocking; it does not wait for the shift to complete. An implementation should complete the operation within the time specified. The default implementation simply changes the value to the final value immediately.- Parameters:
from
- initial value at the beginning of the shiftto
- final value after the shiftmicroseconds
- maximum duration of the shift in microseconds- Throws:
IllegalArgumentException
- if eitherfrom
orto
value does not fall within the allowable range- See Also:
-
toString
Returns a string representation of the float control.
-