A mixer is an audio device with one or more lines. It need not be designed for mixing audio signals. A mixer that actually mixes audio has multiple input (source) lines and at least one output (target) line. The former are often instances of classes that implement SourceDataLine , and the latter, TargetDataLine . Port objects, too, are either source lines or target lines. A mixer can accept prerecorded, loopable sound as input, by having some of its source lines be instances of objects that implement the Clip interface.

Through methods of the Line interface, which Mixer extends, a mixer might provide a set of controls that are global to the mixer. For example, the mixer can have a master gain control. These global controls are distinct from the controls belonging to each of the mixer's individual lines.

Some mixers, especially those with internal digital mixing capabilities, may provide additional capabilities by implementing the DataLine interface.

A mixer can support synchronization of its lines. When one line in a synchronized group is started or stopped, the other lines in the group automatically start or stop simultaneously with the explicitly affected one.

@author
Kara Kytle
@version
1.31, 04/07/14
@since
1.3
Adds a listener to this line. Whenever the line's status changes, the listener's update() method is called with a LineEvent object that describes the change.
Parameters
listenerthe object to add as a listener to this line
See Also
#removeLineListener , LineListener#update , LineEvent
Closes the line, indicating that any system resources in use by the line can be released. If this operation succeeds, the line is marked closed and a CLOSE event is dispatched to the line's listeners.
Throws
SecurityExceptionif the line cannot be closed due to security restrictions.
See Also
#open , #isOpen , LineEvent
Obtains a control of the specified type, if there is any. Some controls may only be available when the line is open.
Parameters
controlthe type of the requested control
Return
a control of the specified type
Throws
IllegalArgumentExceptionif a control of the specified type is not supported
See Also
#getControls , #isControlSupported(Control.Type control)
Obtains the set of controls associated with this line. Some controls may only be available when the line is open. If there are no controls, this method returns an array of length 0.
Return
the array of controls
See Also
#getControl
Obtains a line that is available for use and that matches the description in the specified Line.Info object.

If a DataLine is requested, and info is an instance of DataLine.Info specifying at least one fully qualified audio format, the last one will be used as the default format of the returned DataLine.

Parameters
infodescribes the desired line
Throws
LineUnavailableExceptionif a matching line is not available due to resource restrictions
IllegalArgumentExceptionif this mixer does not support any lines matching the description
SecurityExceptionif a matching line is not available due to security restrictions
Obtains the Line.Info object describing this line.
Return
description of the line
Obtains the approximate maximum number of lines of the requested type that can be open simultaneously on the mixer. Certain types of mixers do not have a hard bound and may allow opening more lines. Since certain lines are a shared resource, a mixer may not be able to open the maximum number of lines if another process has opened lines of this mixer. The requested type is any line that matches the description in the provided Line.Info object. For example, if the info object represents a speaker port, and the mixer supports exactly one speaker port, this method should return 1. If the info object represents a source data line and the mixer supports the use of 32 source data lines simultaneously, the return value should be 32. If there is no limit, this function returns AudioSystem.NOT_SPECIFIED.
Parameters
infoa Line.Info that describes the line for which the number of supported instances is queried
Return
the maximum number of matching lines supported, or AudioSystem.NOT_SPECIFIED
Obtains information about this mixer, including the product's name, version, vendor, etc.
Return
a mixer info object that describes this mixer
See Also
Mixer.Info
Obtains information about the set of source lines supported by this mixer. Some source lines may only be available when this mixer is open.
Return
array of Line.Info objects representing source lines for this mixer. If no source lines are supported, an array of length 0 is returned.
Obtains information about source lines of a particular type supported by the mixer. Some source lines may only be available when this mixer is open.
Parameters
infoa Line.Info object describing lines about which information is queried
Return
an array of Line.Info objects describing source lines matching the type requested. If no matching source lines are supported, an array of length 0 is returned.
Obtains the set of all source lines currently open to this mixer.
Return
the source lines currently open to the mixer. If no source lines are currently open to this mixer, an array of length 0 is returned.
Throws
SecurityExceptionif the matching lines are not available due to security restrictions
Obtains information about the set of target lines supported by this mixer. Some target lines may only be available when this mixer is open.
Return
array of Line.Info objects representing target lines for this mixer. If no target lines are supported, an array of length 0 is returned.
Obtains information about target lines of a particular type supported by the mixer. Some target lines may only be available when this mixer is open.
Parameters
infoa Line.Info object describing lines about which information is queried
Return
an array of Line.Info objects describing target lines matching the type requested. If no matching target lines are supported, an array of length 0 is returned.
Obtains the set of all target lines currently open from this mixer.
Return
target lines currently open from the mixer. If no target lines are currently open from this mixer, an array of length 0 is returned.
Throws
SecurityExceptionif the matching lines are not available due to security restrictions
Indicates whether the line supports a control of the specified type. Some controls may only be available when the line is open.
Parameters
controlthe type of the control for which support is queried
Return
true if at least one control of the specified type is supported, otherwise false.
Indicates whether the mixer supports a line (or lines) that match the specified Line.Info object. Some lines may only be supported when this mixer is open.
Parameters
infodescribes the line for which support is queried
Return
true if at least one matching line is supported, false otherwise
Indicates whether the line is open, meaning that it has reserved system resources and is operational, although it might not currently be playing or capturing sound.
Return
true if the line is open, otherwise false
See Also
#open() , #close()
Reports whether this mixer supports synchronization of the specified set of lines.
Parameters
linesthe set of lines for which synchronization support is queried
maintainSynctrue if the synchronization must be precisely maintained (i.e., the synchronization must be sample-accurate) at all times during operation of the lines , or false if precise synchronization is required only during start and stop operations
Return
true if the lines can be synchronized, false otherwise
Opens the line, indicating that it should acquire any required system resources and become operational. If this operation succeeds, the line is marked as open, and an OPEN event is dispatched to the line's listeners.

Note that some lines, once closed, cannot be reopened. Attempts to reopen such a line will always result in an LineUnavailableException.

Some types of lines have configurable properties that may affect resource allocation. For example, a DataLine must be opened with a particular format and buffer size. Such lines should provide a mechanism for configuring these properties, such as an additional open method or methods which allow an application to specify the desired settings.

This method takes no arguments, and opens the line with the current settings. For SourceDataLine and TargetDataLine objects, this means that the line is opened with default settings. For a Clip , however, the buffer size is determined when data is loaded. Since this method does not allow the application to specify any data to load, an IllegalArgumentException is thrown. Therefore, you should instead use one of the open methods provided in the Clip interface to load data into the Clip.

For DataLine's, if the DataLine.Info object which was used to retrieve the line, specifies at least one fully qualified audio format, the last one will be used as the default format.

Throws
IllegalArgumentExceptionif this method is called on a Clip instance.
LineUnavailableExceptionif the line cannot be opened due to resource restrictions.
SecurityExceptionif the line cannot be opened due to security restrictions.
See Also
#close , #isOpen , LineEvent , DataLine , Clip#open(AudioFormat, byte[], int, int) , Clip#open(AudioInputStream)
Removes the specified listener from this line's list of listeners.
Parameters
listenerlistener to remove
See Also
#addLineListener
Synchronizes two or more lines. Any subsequent command that starts or stops audio playback or capture for one of these lines will exert the same effect on the other lines in the group, so that they start or stop playing or capturing data simultaneously.
Parameters
linesthe lines that should be synchronized
maintainSynctrue if the synchronization must be precisely maintained (i.e., the synchronization must be sample-accurate) at all times during operation of the lines , or false if precise synchronization is required only during start and stop operations
Throws
IllegalArgumentExceptionif the lines cannot be synchronized. This may occur if the lines are of different types or have different formats for which this mixer does not support synchronization, or if all lines specified do not belong to this mixer.
Releases synchronization for the specified lines. The array must be identical to one for which synchronization has already been established; otherwise an exception may be thrown. However, null may be specified, in which case all currently synchronized lines that belong to this mixer are unsynchronized.
Parameters
linesthe synchronized lines for which synchronization should be released, or null for all this mixer's synchronized lines
Throws
IllegalArgumentExceptionif the lines cannot be unsynchronized. This may occur if the argument specified does not exactly match a set of lines for which synchronization has already been established.