The
AudioSystem
class acts as the entry point to the sampled-audio system resources. This class lets you query and access the mixers that are installed on the system.
AudioSystem
includes a number of methods for converting audio data between different formats, and for translating between audio files and streams. It also provides a method for obtaining a
Line
directly from the
AudioSystem
without dealing explicitly with mixers.
Properties can be used to specify the default mixer for specific line types. Both system properties and a properties file are considered. The "sound.properties" properties file is read from an implementation-specific location (typically it is the conf
directory in the Java installation directory). The optional "javax.sound.config.file" system property can be used to specify the properties file that will be read as the initial configuration. If a property exists both as a system property and in the properties file, the system property takes precedence. If none is specified, a suitable default is chosen among the available devices. The syntax of the properties file is specified in Properties.load
. The following table lists the available property keys and which methods consider them:
The property value consists of the provider class name and the mixer name, separated by the hash mark ("#"). The provider class name is the fully-qualified name of a concrete
mixer provider
class. The mixer name is matched against the
String
returned by the
getName
method of
Mixer.Info
. Either the class name, or the mixer name may be omitted. If only the class name is specified, the trailing hash mark is optional.
If the provider class is specified, and it can be successfully retrieved from the installed providers, the list of Mixer.Info
objects is retrieved from the provider. Otherwise, or when these mixers do not provide a subsequent match, the list is retrieved from getMixerInfo()
to contain all available Mixer.Info
objects.
If a mixer name is specified, the resulting list of Mixer.Info
objects is searched: the first one with a matching name, and whose Mixer
provides the respective line interface, will be returned. If no matching Mixer.Info
object is found, or the mixer name is not specified, the first mixer from the resulting list, which provides the respective line interface, will be returned.
For example, the property javax.sound.sampled.Clip
with a value "com.sun.media.sound.MixerProvider#SunClip"
will have the following consequences when getLine
is called requesting a Clip
instance: if the class com.sun.media.sound.MixerProvider
exists in the list of installed mixer providers, the first Clip
from the first mixer with name "SunClip"
will be returned. If it cannot be found, the first Clip
from the first mixer of the specified provider will be returned, regardless of name. If there is none, the first Clip
from the first Mixer
with name "SunClip"
in the list of all mixers (as returned by getMixerInfo
) will be returned, or, if not found, the first Clip
of the first Mixer
that can be found in the list of all mixers is returned. If that fails, too, an IllegalArgumentException
is thrown.