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HTTP: The device must support HTTP 1.1 download ( not streaming ) of all
supported media formats. This is because the MMAPI itself does not support
any mandatory protocols, nor does it specify which media types require a specific
protocol.
MIDI : The device must support MIDI file playback. This is because many games
are enhanced by suitable audio; MIDI provides a compact representation of that
audio. In addition, the device must also support the VolumeControl for MIDI
playback.
Tone sequences : The device must support tone sequences as an additional route to
provide audio for games and other applications.
Snapshot format : If the MMAPI implementation supports the video feature set and
video image capture, the snapshot format must include JPEG encoding as an
encoding option.
Frustratingly, there's a lot that the JTWI doesn't say about the MMAPI, such as
whether it should support streaming and digital audio formats such as WAV or MP3.
By setting the bar as low as it does, though, it includes many commercially available
devices, and it has helped the Java ME developer community standardize many
aspects of multimedia development for wireless games.
Understanding the MSA
The JTWI is an excellent first step in unifying Java ME APIs for the mobile-phone market.
However, it is seriously dated; the fast pace of hardware and software development for
mobile devices guaranteed that by the time the JTWI would be widely adopted and refer-
enced, it would not address further fragmentation from additional features such as the
FCOP, additional MMAPI and SVG support, and other features such as Bluetooth and the
Mobile 3D Graphics API, neither of which I have even discussed at any length this topic.
Consequently, the Java ME community has produced JSRs 248 and 249 to define the
MSA—a platform architecture more broad than the one that the JTWI defines, yet still
targeted at high-volume devices. Moreover, while the JTWI largely captured the state of
the Java ME device market at the time of its acceptance, the MSA aims to describe not
only features that are already available on some devices, but also those that experts
expect will be prevalent in the foreseeable future.
There are already two versions of the MSA: MSA 1.0, which JSR 248 defines; and
MSA2, which JSR 249 defines. MSA 1.0 is fully accepted by the JCP; the maintenance
release of JSR 248 was released as I wrote this chapter. By comparison, JSR 249 is a wee
little thing; while its predecessor JSR 248 was being approved, JSR 249 was in private draft
 
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