Java Reference
In-Depth Information
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Location
: The Location API that JSR 179 describes must be included if the device
has a GPS receiver or other position-location acquisitions subsystem to enable
location-based applications.
•
SIP
: SIP is the protocol of choice for IP-based telephony networks to establish and
manage voice call handling. MSA 1.0 requires that a compliant device includes the
package that enhances GCF support by providing SIP as JSR 180 specifies is
required.
•
Content handling
: The Content Handler API that JSR 211 defines permits one Java
application (or MIDlet) to launch another based on the content types it supports.
•
Advanced multimedia
: The Advanced Multimedia Supplements (AMMS) API,
which I mention briefly in Chapter 16, must be included to permit developers to
use enhanced camera support, 3D audio, support for an internal radio, and supe-
rior image encoding and processing capabilities.
•
Internationalization
: MIDlets and applications for Java ME are hard to internation-
alize; there's no good way to isolate localized application resources from the source
code or dynamically identify those resources at runtime. JSR 238 provides a stan-
dard means for accomplishing this, and must be included.
Evolving for the Future: MSA2
JSR 249 defines MSA2, a collection of requirements that is backward compatible with
MSA 1.0. Written by an expert group with substantially the same composition as JSR 248,
MSA2 addresses changes in the Java ME marketplace that have occurred between the
time JSR 248 development started and ended. It defines three platforms:
•
MSA2 Limited
: For low-tier, mass-market phones.
•
MSA2 Subset
: Targeted for mid-tier, mass-market phones, this is a superset of
MSA2 Limited with additional requirements.
•
MSA2
: Targeted for high-tier devices, this is a superset of MSA2 Subset with addi-
tional requirements.
Like JSR 248, JSR 249 defines these platforms using the notion of mandatory require-
ments and conditionally mandatory requirements, and it not only specifies a collection
of JSRs that each platform must support, but it also provides additional requirements
about those JSRs, as well as additional requirements for the target platform as a whole.
Some of these requirements are inherited from MSA 1.0 and from the JTWI; others are
new to MSA2. Hardware requirements (such as screen and heap capabilities) remain the
