The Symbian OS (779886), страница 67
Текст из файла (страница 67)
File system access is implemented throughthe GCF communications framework, which generalizes frameworksupport for HTTP, IP and socket-based connections.• The Bluetooth component implements two optional MIDP2.0 Bluetooth 1.0 (JSR-082) packages: the core Bluetooth API and the ObjectExchange (OBEX) API.• The Wireless Messaging API (WMA) provides platform-independentaccess to wireless communication resources, enables send and receiveof SMS messaging, including SMS push, on GSM, CDMA and othernetworks supporting asynchronous messaging protocols.Both Bluetooth 1.0 and WMA 1.1 add ‘push’ capability to the supportfor MIDlets, allowing a MIDlet to respond either statically (at install time)COMPONENT COLLECTIONS315CLDC1.1JavaIOJavaLangFigure 12.8JavaUtilitiesCLDC 1.1 componentsor dynamically (programmatically) to an incoming WMA or Bluetoothconnection (i.e. to a ‘message’).
Both implementations are integrated intothe GCF communications framework.CLDC 1.1 CollectionThis component implements CLDC 1.1 Java class libraries (JSR-118).CLDC 1.1 specifies the core subset of the Java language required tosupport MIDlets. The language libraries define basic types and objects,including Byte, Integer, Object and Thread; the I/O libraries define thedata-stream-based input–output APIs, as well as APIs for reading andwriting bytes and basic Java types; the utilities library supplies basicutility classes, including Date and Time, and collection classes includingHashtable, Stack and Vector (see Figure 12.8).Table 12.3 CLDC 1.1 ComponentsComponent NameDevelopment NameJava LangJAVA.LANGJava IOJAVA.IOJava UtilitiesJAVA.UTILVirtual Machine CollectionThe CLDC-HI 1.1 component is the Sun CLDC HotSpot ImplementationVM, which is part of the CLDC 1.1 specification (JSR-139). The HotSpotVirtualMachineCLDCHi1.1Figure 12.9Virtual Machine components316THE JAVA ME SUBSYSTEMTable 12.4 Virtual Machine ComponentsComponent NameDevelopment NameCLDC HI 1.1CLDCHIVM applies a variety of advanced performance-optimization techniques todeliver a highly competitive execution environment for Java applications.See Figure 12.9.Low-Level Plug-ins CollectionThese plug-ins allow customization of the CLDC run-time framework andbind LCDUI to the underlying graphics system.
See Figure 12.10.Table 12.5 Low-Level Plug-insComponent NameDevelopment NameRuntime Plug-inMIDP2RUNTIMELCDUI Plug-inLCDUIB• The Runtime plug-in component is the MIDP 2.0 run-time plug-inmodule. It can be customized by the licensee.• The LCDUI plug-in component consists of low-level graphics APIswith direct screen access, implemented as a plug-in that is replacedwith an alternative implementation.Bluetooth and SMS Push CollectionThese plug-ins bind the Bluetooth 1.0 and WMA 1.1 packages to theunderlying system.
See Figure 12.11.Low LevelPluginsLCDUIPluginRuntimePluginFigure 12.10 Low-Level Plug-insCOMPONENT COLLECTIONSBluetooth &SMS PushBtooth.1.0WMA1.1Figure 12.11 Bluetooth and SMS Push componentsTable 12.6 Bluetooth and SMS Push ComponentsComponent NameDevelopment NameBluetooth 1.0 PushPlug-inBLUETOOTHWMA 1.1. Push Plug-inWMA31713Notes on the Evolution of Symbian OS13.1 The State of the ArtSymbian OS reached market for the first time towards the end of 2000,following on from the Psion EPOC32 releases. The last release of EPOC32was Release 5; the first release of Symbian OS was Symbian OS v6.0.The most recent release is Symbian OS v9, but Symbian OS v8remains very much an active platform on which new products arestill being developed and brought to market.
Phones based on earlierreleases still ship in their millions, even though Symbian’s licensees havemoved up to the latest releases for new products. Indeed until relativelyrecently, phones based on Symbian OS v6.1 continued to ship in quantity,particularly in Japan. Since then, Japanese licensees have led the wayin adopting the new real-time kernel architecture, and have brought tomarket new 3G phones based on Symbian OS v8.1b and are likely tofollow with phones based on Symbian OS v9.In other markets, licensees are shipping new phones based both onSymbian OS v9 (platform security, new real-time kernel) and v8 (originalkernel architecture). Symbian OS v7 (Sony Ericsson P910, MotorolaA1000 and FOMA M1000) remains a volume-selling release and phonesbased on Symbian OS v6.1 (N-Gage QD) are still shipping.At the time of writing, in late 2006, phones are shipping on all releasesfrom Symbian OS v6.1 to Symbian OS v9.1, although new productpipelines from licensees are based on Symbian OS v8 and v9.13.2 Summary of Symbian OS v6 ReleasesSymbian OS v6 was the immediate result of a major and long-runningproject, working with Nokia as lead licensee, to re-engineer and rearchitect Symbian OS from its EPOC32 baseline (ER5U).
EPOC32 didsupport some phone and messaging functions, for example ‘two-box’320NOTES ON THE EVOLUTION OF SYMBIAN OStelephony solutions in which an EPOC-based PDA could use a GSMmobile phone as a dialup modem, as well as driving it directly to sendSMS messages and synchronize with the SIM phone book. However,EPOC remained substantially PDA-centric. Even more importantly, itsEikon GUI was not suitable for phones.Among the most significant changes in Symbian OS v6, therefore, wasthe refactoring of Uikon to support multiple user interface implementations, so called ‘variant UIs’, and the more general re-architecting ofphone-centric functionality to suit a true phone operating system. TheSymbian OS v6 system architecture was based on a component-basedrelease model and representation.Symbian OS v6.0Symbian OS v6.0 was the common platform for what were branded as theCrystal and Quartz reference designs, in keeping with Symbian’s DFRDstrategy.One Crystal-based product, the Nokia 9210 Communicator, wasbrought to market.
No Quartz devices reached market (although devicesfrom Ericsson and Sanyo were demonstrated, including at 3GSM inCannes).The system architecture of Symbian OS v6.0 was based on a components representation inherited from the original Psion EPOC32 binarycomponent release model.Symbian OS v6.1Symbian OS v6.1 (announced in March 2001 at CeBIT) was the originalplatform for the Nokia S60 UI (which began life as the Pearl DFRD andlaunched as Series 60) The first Symbian OS v6.1/S60 phone (arguably,the first Symbian OS phone as opposed to PDA–phone hybrid) was theNokia 7650. Other Symbian OS v6.1/S60 phones were brought to marketby Panasonic, Sendo and Siemens.Symbian OS v6.1 was very much an addition to the Symbian OS v6.0baseline.
No functionality was deprecated (although there were one ortwo significant reworkings); some functionality was added (around 150new classes and other types). In almost all cases, changes were bothbinary and source compatible. Significant changes included:• UI Framework and UI Toolkit changes and related changes to FEP andText Formatting• Application Services changes including new Contacts Model fileformat, new Chinese calendar and locale support, including CharacterEncoding Conversion updates, and improved VCard and VCalendarsupportSUMMARY OF SYMBIAN OS V7 RELEASES321• OS Services changes including major Bluetooth revision (full Bluetooth 1.1 compliance), Infrared IrObex over Bluetooth, screen driversplit out from BitGDI, 256-color-mode palette support added toFont & Bitmap Server, Free Type enhancements, Multimedia Serverstreaming added, new WAP Push and messaging functionality, telephony support for GSM/GPRS and SIM Toolkit, and Comms Databaseimprovements.13.3 Summary of Symbian OS v7 ReleasesSymbian OS v7 was significant as the platform for the first UIQ phones.It also provided Symbian with its first real taste of the problems offragmentation, with the divergence of Symbian OS v7.0 from SymbianOS v6.1 threatening the common platform model for UIQ and S60,subsequently corrected by the Symbian OS v7.0s release.Symbian OS v7.0 was the platform for the Sony Ericsson P800 family;Symbian OS v7.0s was the platform for Nokia phones beginning with the6600 and remained the mainstream platform for Nokia phones until the6630 3G phone was released.Symbian OS v7.0Symbian OS v7.0, announced in February 2002 at 3GSM, was theplatform for the UIQ UI (an evolution of the Quartz DFRD).
The firstSymbian OS v7 UIQ phone was the Sony Ericsson P800 (announced inQ1 2002 and released in Q4 2002).Symbian OS v7.0 was, at a functional level, substantially backwardscompatible with Symbian OS v6.1, however there were numerouscompatibility breaks, as well as significant new functionality added andsignificant restructuring of the UI Framework components to improvethe separation between the framework support and the overlaying userinterface. The TechView reference user interface components were alsointroduced (although TechView never became a complete reference userinterface implementation).Symbian OS v 7.0 also significantly reworked the source tree, introducing a subsystem-based release model and representation.
Subsequently,Symbian OS v7.0 became the baseline for the architecture representation based on the system model, which has become Symbian’s standardarchitectural representation for releases from Symbian OS v7.0 forwards.Among the most significant changes from Symbian OS v6.1 were:• Application support◦ The Time/World application refactored into Alarm Server andWorld Server322NOTES ON THE EVOLUTION OF SYMBIAN OS◦ New Help file format; Agenda and Contact format changes (forvCard and vCal)◦ System agent updated to support two-box system.◦ Improvements to text handling and text views (formatting) supportfor user interface◦ Microsoft Word and Excel converter support• UI and Graphics◦ Further refactoring of Uikon to support user interface separationand pluggable Look-And-Feel◦ New standard controls including animation in menus, menuhighlighting options, variable-height list items, customizable textwrapping, line breaks, automatic hyphenation (editable windows),improved error handling, a generic dialog server, flip support, andmany other minor enhancements◦ Graphics changes for anti-aliasing, key click and long keypresssupport, direct screen access and 2D hardware-acceleration support, hardware bitmaps, font name aliases, polygon fill, bitmapscaling, fading◦ Front End Processor Base optimizations◦ New TechView test user interface•Multimedia◦ Media Server updates to support audio and video streaming andgraphics acceleration◦ Improved audio codec support• Comms and Telephony◦ Telephony re-architecture introduced Multimode ETel (in placeof the Basic, Advanced and GPRS extensions), enabling CDMAsupport and performance improvements◦ New 3rd-party telephony API, non-third party APIs restricted◦ New SIM Toolkit phone applications support◦ New reference and test TSY implementations•Networking◦ Dual v4/v6 IP stack introduced, networking support for packettelephony (GPRS) and IPSec, including integration with new Multimode ETel◦ Socket Server changes relating to IPv6, internet sockets, and securesocketsSUMMARY OF SYMBIAN OS V7 RELEASES323◦ Improved emulator Ethernet support• Bluetooth and short link: Simplified HCI implementation to assistporting• WAP and browsing◦ WAP stack withdrawn (reliance on licensee implementations),WAP messaging implementation refactored◦ HTTP Client API added◦ WSP Adaptation Layer and Protocol Handler APIs◦ Opera-specific web-browser support component added•Messaging◦ Support introduced for multimedia messaging (MMS) includingSMIL message content markup.
![](https://s.studizba.com/z.php?f=/templates/si/i/noavatar.png&w=100&h=100&t=1"){kind=avatar}
