計算機相關專業(yè)畢業(yè)設計外文翻譯--移動設備的應用平臺—j2me簡介

1、<p>　　附件1：外文資料翻譯譯文</p><p>　　移動設備的應用平臺—J2ME簡介</p><p>　　1.什么是J2ME:</p><p>　　J2ME(Java 2 Micro Edition)是Java 2的一個組成部分，它與J2SE、J2EE并稱。根據(jù)Sun的定義：J2ME是一種高度優(yōu)化的Java運行環(huán)境，主要針對消費類電子設備的，例如蜂窩

2、電話和可視電話、數(shù)字機頂盒、汽車導航系統(tǒng)等等。J2ME技術在1999年的JavaOne Developer Conference大會上正式推出，它將Java語言的與平臺無關的特性移植到小型電子設備上,允許移動無線設備之間共享應用程序。</p><p>　　J2ME在設計其規(guī)格的時候，遵循著對于各種不同的裝置而造出一個單一的開發(fā)系統(tǒng)是沒有意義的事」這個基本原則。于是 J2ME 先將所有的嵌入式裝置大體上區(qū)分為兩種

3、:一種是運算功能有限、電力供應也有限的嵌入式裝置(比方說PDA 、手機)；另外一種則是運算能力相對較佳、并請在電力供應上相對比較充足的嵌入式裝置 (比方說冷氣機、電冰箱、電視機上盒 (set-top box))。因為這兩種型態(tài)的嵌入式裝置，所以Java 引入了一個叫做Configuration 的概念，然后把上述運算功能有限、電力有限的嵌入式裝置定義Connected Limited Device Configuration(CLDC)

4、規(guī)格之中；而另外一種裝置則規(guī)范為 Connected Device Configuration(CDC)規(guī)格。也就是說,J2ME 先把所有的嵌入式裝置利Configuration 的概念區(qū)隔成兩種抽象的型態(tài)。 </p><p>　　其實在這里大家可以把Configuration 當作是J2ME 對于兩種類型嵌入式裝置的規(guī)格，而這些規(guī)格之中定義了這些裝置至少要符合的運算能力、供電能力、記憶體大小等規(guī)范，同時也定了一

5、組在這些裝置上執(zhí)行的 Java 程序所能使用的類別函式庫、這些規(guī)范之中所定義的類別函式庫為 Java 標準核心類別函式庫的子集合以及與該型態(tài)裝置特性相符的擴充類別函式庫。比方就CLDC 的規(guī)范來說，可以支援的核心類別函式庫為java.lang.* 、java.io.*、java.util.*，而支援的擴充類別函式庫為java.microedition.io.*。區(qū)分出兩種主要的Configuration 之后，J2ME 接著在定義出Pr

6、ofile的概念。Profile 是架構(gòu)在Configuration 之上的規(guī)格。之所以有Profile的概念，是為了要更明確地區(qū)分出各種嵌入式裝置上Java 程序該如何開發(fā)以及它們應該具有哪些功能。因此Profile 之中定義了與特定嵌入式裝置非常相關的擴充類別函式庫，而 Java 程序在各種嵌入式裝置上的使用者介面該如何呈現(xiàn)就是定義在Profile 里頭。Profile</p><p>　　2. J2ME W

7、ireless Toolkit 2.2 新改進</p><p>　　J2ME Wireless Toolkit 已經(jīng)成為 J2ME 開發(fā)應用程序的事實標準工具包。自從 2000 年初次亮相以來，該工具包一直在發(fā)展以趕上移動 Java 技術外觀上快速改變的步伐。不要被從 2.1 版本以來的小改變所誤導。新的工具包在四個重要的領域支持　Java Community Process (JCP)　所指定的新的可選 API

8、：3D 圖形、多媒體通信、藍牙連網(wǎng)（Bluetooth networking）和數(shù)據(jù)管理。本文將描述這些新的 API 并且向您展示如何在工具包中實現(xiàn)他們。在這之前，讓我們贊美一下更新后的 DefaultColorPhone 模擬器皮膚，自從 2.1 版本以來，該皮膚已有了一個更大的屏幕（320 x 240, 或 QVGA）和更多的顏色（4096 色而不是 256 色）。</p><p>　　2.1移動 3D 圖形

9、:</p><p>　　JSR 184, 即 Mobile 3D 圖形 API for J2ME (M3G) 在一個集成軟件包中提供了三維圖形功能，適用于支持最為廣泛采用的 J2ME 軟件棧、有限連接設備配置（CLDC）和移動信息設備描述（MIDP）的設備。API 為顯示 3D 內(nèi)容提供了兩種 API。立即模式 API 使應用程序能夠直接創(chuàng)建和操縱 3D元素。這一層之上是一個場景圖 API，也稱為保留模

10、式，能夠提早加載并顯示已設計的整個3D 場景。應用程序可以采用最適合的 API，或保留模式與立即模式的組合。JSR 184 規(guī)范還為場景圖定義了一種文件格式－.m3g。</p><p>　　該工具包的模擬器全面支持 JSR 184，并且有幾個 MIDlet 展示了 API 在 Demo3D 項目中的功能。Life3D 演示了立即模式的使用。PogoRoo 是一個的交互的演示，特點是顯示一只跳躍的袋鼠。</p

11、><p><b>　　2.2多媒體通信:</b></p><p>　　J2ME Wireless Toolkit 長期支持 JSR 120、Wireless Messaging API（WMA）的1.1版本；新版本支持 WMA 2.0（JSR 205），其把WMA的功能擴展到包括多媒體通信。</p><p>　　在工具包中，通信發(fā)生于模擬的環(huán)境中。

12、如果多次運行模擬器，模擬器上的應用程序能夠相互通信，并且可以使用工具包方便的 WMA Console 實用程序在同一環(huán)境中與應用程序交換消息。通信可以遵照以下三種標準協(xié)議之一：短消息服務（Short Message Service，SMS）、蜂窩廣播服務（Cell Broadcast Service，CBS）或工具包 2.2 版本中的新協(xié)議－多媒體通信服務（MMS）。</p><p>　　您可以標記 MMS 消息

13、，并向消息添加任何文件集合。而且，現(xiàn)在網(wǎng)絡監(jiān)視器能夠顯示模擬器發(fā)送或接收的 MMS 消息。</p><p>　　2.3藍牙和 OBEX：</p><p>　　J2ME Wireless Toolkit 模擬器支持 JSR 82，即 Java API for Bluetooth，包括兩個獨立的 API：</p><p>　　藍牙 API 為藍牙無線網(wǎng)絡提供了接口，包括

14、設備恢復和數(shù)據(jù)交換。</p><p>　　OBEX API 允許應用程序在藍牙或其他通信信道上使用對象交換（Object Exchange，OBEX）協(xié)議。</p><p>　　該工具包允許在即使沒有實際藍牙硬件的情況下，也可以開發(fā)和測試采用藍牙技術的應用程序。該工具包模擬藍牙環(huán)境，您可以在該環(huán)境中運行可相互發(fā)現(xiàn)的多個模擬器實例和使用藍牙 API 交換數(shù)據(jù)。</p><

15、p>　　應用程序?qū)嵗?BluetoothDemo 顯示了如何從一個模擬器將圖像傳輸?shù)搅硪粋€模擬器。</p><p>　　J2ME Wireless Toolkit 通過模擬的藍牙和紅外連接上實現(xiàn) OBEX 傳輸。模擬的紅外連接遵循 Infrared Data Association 定義的 IrDA 標準。工具包在多個運行的模擬器之間模擬紅外傳輸。</p><p>　　您可以使用工具

16、包參數(shù)中的 Bluetooth/OBEX 標簽來配置藍牙和 OBEX 環(huán)境。其控制了諸如模擬器在模擬的藍牙環(huán)境中試圖用多長時間去發(fā)現(xiàn)其他設備，以及最大數(shù)據(jù)包大小等參數(shù)。請參見工具包的用戶指南獲取更多的詳細信息。</p><p>　　2.4無線開發(fā)工具包（WTK）：</p><p>　　WTK 的全稱是Sun J2ME Wireless Toolkit —— Sun的無線開發(fā)工具包。這一工具

17、包的設計目的是為了幫助開發(fā)人員簡化j2me的開發(fā)過程。使用其中的工具可以開發(fā)與 Java Technology for the Wireless Industry (JTWI, JSR 185) 規(guī)范兼容的設備上運行的j2me 應用程序。該工具箱包含了完整的生成工具、實用程序以及設備仿真器。到本文寫作時為止可以獲取有四個版本，分別是1.0.4, 2.0, 2.1和2.2。每個版本都包括英語，日語，簡體中文，繁體中文4個語種包。WTK是S

18、un提供的一個開發(fā)工具包。目前各大手機廠商往往把WTK經(jīng)過自身的簡化與改裝，推出適合自身產(chǎn)品，如SonyEricsson，Nokia Developer’s suit等，都屬于此種類型；而通過JBuilder, Eclipse等IDE，J2ME開發(fā)包工具可以被綁定在這些集成開發(fā)環(huán)境中，進一步提高開發(fā)效率。 </p><p>　　無論哪個版本的WTK都會包括以下幾個目錄： 　　</p><p&g

19、t;　　appdb目錄： RMS數(shù)據(jù)庫信息 　　</p><p>　　apps目錄： WTK自帶的demo程序 　　</p><p>　　bin目錄： J2ME開發(fā)工具執(zhí)行文件 　　</p><p>　　docs目錄： 各種幫助與說明文件 　　</p><p>　　lib目錄： J2ME程序庫，Jar包與控制文件 　　</p>

20、<p>　　session目錄：性能監(jiān)控保存信息 　　</p><p>　　wtklib目錄： JWTK主程序與模擬器外觀。</p><p>　　2.5 J2me數(shù)字簽名：</p><p>　　得到一個證書后就可以對j2me的jad文件進行簽名。這里有一些與簽名相關的需要注意的一些問題。1. 想要安裝簽過名的軟件，就必須通過jad來安裝。我們知道j2me程

21、序生成后會有jad和jar兩個文件，一般情況下我們只需要安裝jar文件就可以了。例如我會將jar文件通過藍牙傳到手機上，再進行安裝。但如果想通過手動安裝簽過名的文件，就要通過jad來安裝，而且要確保jad和jar文件是在相同目錄下。我的做法是通過數(shù)據(jù)線將兩個文件拷入手機的內(nèi)存或存儲卡上，然后通過jad來安裝，這樣安裝好的軟件就是簽過名的軟件了。不會再有總是很煩人的詢問用戶是否允許操作的提示信息。但就我看過的手機看來，應該是不同的手機有不

22、同的表現(xiàn)。例如索愛的手機關于提示仍然是需要用戶自己設置的。諾基亞也是。只是諾基亞的在使用非簽名軟件時用戶無法設置為“總是允許”或“只提示一次”。而簽了名的就可以設置了。2. 編程人員需要注意，像很多功能在未簽名前是可以使用的，例如gps，網(wǎng)絡連接，文件讀寫等。3. 簽過名的軟件有什么好處。簽名就是告訴我們這個軟件是可信的，對用戶最直接的感受就是聯(lián)網(wǎng)或訪問手機文件的時候，收發(fā)短信，彩信，藍牙等，</p><p>　

23、　2.6本地文件和個人信息:</p><p>　　J2ME Wireless Toolkit 支持 JSR 75,即 PDA Optional Packages for the J2ME Platform，它也包括兩個獨立的 API：FileConnection API 提供了 MIDlet 對設備上本地文件系統(tǒng)的訪問。Personal Information Management (PIM) 可選軟件包包括用于

24、操縱聯(lián)系人列表、日程安排和計劃列表的 API。</p><p>　　一臺真實的設備可能有一個能通過使用 FileConnection API 訪問的本地文件系統(tǒng)。在 J2ME Wireless Toolkit 模擬器中，模擬的文件系統(tǒng)作為硬盤上的一個目錄存在。應用程序使用FileConnection可訪問的文件都存放在子目錄<toolkit>\appdb\<skin>\ filesyste

25、m中,此處 <toolkit> 是 J2ME Wireless Toolkit 的安裝目錄，<skin> 是模擬器皮膚的名稱。例如，DefaultColorPhone 模擬器皮膚隨安裝根root1 而產(chǎn)生，包含一個Readme 文件文件的完整路徑為<toolkit>\appdb\DefaultColorPhone\filesystem\root1\Readme。</p><p>

26、;　　您可以從模擬器窗口的菜單種選擇 MIDlet > External events 來管理可用的根目錄。您將看到一個添加和刪除根目錄的小的實用程序窗口。這些操作也將為 registered listener 對象生成事件。</p><p>　　在真實的設備上，個人信息可能以專有格式存儲在內(nèi)存中。模擬器使用硬盤中的一個目錄來存放這些信息，可使用 PIM API 來訪問。所有的信息存儲在 <toolk

27、it>\appdb\pim 目錄中。列表存儲在聯(lián)系人、事件和計劃目錄的子目錄中。例如，聯(lián)系人列表 Contacts 位于 <toolkit>\appdb\pim\contacts\Contacts 目錄中。</p><p>　　在列表目錄內(nèi)，列表項以 Internet Mail Consortium 指定的標準格式存儲。聯(lián)系人以 vCard 格式存儲，日歷和計劃項都以 vCalendar 格式存

28、儲。</p><p>　　J2ME Wireless Toolkit 2.2 不僅僅是一個出色工具的增量更新。它包括了對令人激動的四項新規(guī)范的支持，同時定義了六種新的 API。隨著無線 Java 技術世界的快速發(fā)展，J2ME Wireless Toolkit 緊緊跟隨發(fā)展的步伐并且包含您所需的全部工具。</p><p><b>　　附件2：外文原文</b></p

29、><p>　　Mobile application platform-J2ME profile</p><p>　　1. what is the J2ME</p><p>　　J2ME (Java 2 Micro Edition) is a Java 2 as an integral part of it with J2SE, J2EE said. According

30、 to Sun's definition: J2ME is a highly optimized Java runtime environment, mainly for consumer electronics devices such as cellular phones and video phones, digital set-top boxes, car navigation systems and so on. J2

31、ME technology in 1999, the JavaOne Developer Conference on the formal launch of the General Assembly, which will of the Java language and platform-independent features into a small electr</p><p>　　J2ME in it

32、s design specifications, to follow a "variety of devices to create a single development system is meaningless" the basic principles. So first of all J2ME embedded devices generally divided into two types: One i

33、s the limited computing, power supply is also limited embedded devices (for example, PDA, cell phone); another kind of computing power is relatively better, And in the power supply is relatively sufficient for embedded d

34、evices (for example, air conditioners, refrigerators, TV set</p><p>　　In fact, everyone here can be a Configuration for J2ME two types of specifications for embedded devices, which defines the specifications

35、 of these devices at least in line with the computing power and capacity of power supply, memory, and other norms Size, as well as set A set of these devices on the implementation of the Java program can be used by the t

36、ype of library, these norms are defined by the type of library for the Java standard library's core categories and sub-type device features the</p><p>　　2. What's New in the J2ME Wireless Toolkit 2.

37、2</p><p>　　The award-winning J2ME Wireless Toolkit has become the de facto standard toolkit for developing applications for Java 2, Micro Edition (J2ME). Since its debut in 2000, the toolkit has evolved to k

38、eep pace with the rapidly changing face of mobile Java technology. Don't be misled by the small change in version number from 2.1. The new toolkit supports new optional APIs specified through the Java Community Proce

39、ss (JCP) in four vital areas: 3D graphics, multimedia messaging, Bluetooth networking,an</p><p>　　Before I do, take a moment to admire the updated DefaultColorPhone emulator skin. Since version 2.1, this ski

40、n has gotten a larger screen (320 x 240, or QVGA) and far more colors (4096 instead of 256). </p><p>　　2.1 Mobile 3D Graphics:</p><p>　　JSR 184, the Mobile 3D Graphics API for J2ME (M3G), provid

41、es three-dimensional graphics functionality in a compact package that's appropriate for devices that support the most widely adopted J2ME software stack, the Connected, Limited Device Configuration (CLDC) and the Mob

42、ile Information Device Profile (MIDP). The API provides two APIs for displaying 3D content. The immediate mode API makes it possible for applications to create and manipulate 3D elements directly. On top of this layer is

43、 a sce</p><p>　　The toolkit's emulator fully supports JSR 184 and you'll find several MIDlets that show off the API's capabilities in the Demo3D project. </p><p>　　Life3D demonstrate

44、s the use of immediate mode: PogoRoo is an interactive demonstration that features a bouncing kangaroo:Finally, retainedmode shows how to load and render a scene graph file: </p><p>　　2.2 Multimedia Messagin

45、g:</p><p>　　The J2ME Wireless Toolkit has long supported JSR 120, version 1.1 of the Wireless Messaging API (WMA); the new release supports WMA 2.0 (JSR 205), which expands WMA's capabilities to include

46、Multimedia Messaging. </p><p>　　In the toolkit, messaging takes place in a simulated environment. If you run the emulator multiple times, applications on the emulators can communicate with each other, and yo

47、u can use the toolkit's handy WMA Console utility to exchange messages with the applications in the same environment. Messages may conform to any of three standard protocols: Short Message Service (SMS), Cell Broadca

48、st Service (CBS), or - new in version 2.2 of the toolkit - Multimedia Messaging Service (MMS). </p><p>　　You can address MMS messages and add any collection of files to the message. </p><p>　　Fu

49、rthermore, the network monitor now displays MMS messages that are sent or received by the emulator. </p><p>　　2.3 Bluetooth and OBEX:</p><p>　　The J2ME Wireless Toolkit emulator supports JSR 82,

50、 the Java APIs for Bluetooth, which includes two independent APIs: The Bluetooth API provides an interface to Bluetooth wireless networking, including device discovery and data exchange. </p><p>　　The O

51、BEX API allows applications to use the Object Exchange (OBEX) </p><p>　　protocol over Bluetooth or other communication channels. </p><p>　　The toolkit allows you to develop and test applications

52、 that use Bluetooth technology even if you don't have any actual Bluetooth hardware. The toolkit simulates a Bluetooth environment, in which you can run multiple emulator instances that can discover each other and ex

53、change data using the Bluetooth API. </p><p>　　An example application, BluetoothDemo, shows how to transfer imagesfrom one emulator to another. </p><p>　　The J2ME Wireless Toolkit implements OBE

54、X transfer over simulated Bluetooth and infrared connections. The simulated infrared connection </p><p>　　follows the IrDA standard defined by the Infrared Data Association. The toolkit simulates infrared tr

55、ansfers between multiple running emulators. </p><p>　　You can configure the Bluetooth and OBEX environment using the Bluetooth/OBEX tab in the toolkit preferences. This controls such </p><p>　　p

56、arameters as how long the emulator attempts to discover other devices in the simulated Bluetooth environment and the maximum packet size. See the toolkit's User's Guide for more details. </p><p>　　2.

57、4 Wireless development kit（WTK）：</p><p>　　WTK full name is from J2ME Wireless Toolkit - from Wireless development kit. This kit are designed to help developers simplified from j2me development process. Use o

58、ne of the tools can develop with the Wireless Technology for Java (JSR 185, judge not JTWI standardizing compatible equipment running on j2me applications. The kit contains a full set of generation tool, practical proced

59、ures and equipment emulator. When writing to text so far can gain four versions, respectively is 1.0.4, 2.0, 2.1 an</p><p>　　No matter which version WTK will include the following categories: </p><

60、;p>　　Appdb directory: the RMS information from a database </p><p>　　Apps directory: WTK own produce professional demo programs </p><p>　　Bin directory: J2ME development tools executable files

61、 </p><p>　　Docs directory: all kinds of help and documentation </p><p>　　The lib directory: J2ME program libraries, Jar wrapped and control documents </p><p>　　Session directory: pe

62、rformance monitoring conservation information </p><p>　　Wtklib directory: JWTK main program and simulator appearance. </p><p>　　2.5 J2me digital signature ：</p><p>　　Get a certifica

63、te of the j2me jad files for signature. Here are some and autograph related need to pay attention to some problems. 1. Want to install signed the software, you must pass jad to install. We know the j2me program generator

64、 will have the jar jad and two files, in the ordinary circumstances we only need to install the jar file is ok. For example I would jar file via bluetooth to phone, install later. But if you want to through installed man

65、ually signed documents, will pass through jad</p><p>　　2.6 Local Files and Personal Information：</p><p>　　The J2ME Wireless Toolkit supports JSR 75, the PDA Optional Packages for the J2ME Platf

66、orm, which also includes two independent APIs: </p><p>　　The FileConnection API gives MIDlets access to a local file system on the device. </p><p>　　The Personal Information Management (PIM) opt

67、ional package includes APIs for manipulating contact lists, calendars, and to-do lists.</p><p>　　A real device may have a local file system which can be accessed using the FileConnection API. In the J2ME Wir

68、eless Toolkit emulator, a simulated file system is maintained as a directory on your hard disk.</p><p>　　The files your application can access using FileConnection are stored in subdirectories of <toolkit

69、>\appdb\<skin>\filesystem, where <toolkit> is the installation directory of the J2ME Wireless Toolkit and <skin> is the name of the emulator skin. For example, the DefaultColorPhone emulator skin com

70、es with a root directory installed called root1, which contains a file called Readme. The file's full path is <toolkit>\appdb\DefaultColorPhone\filesystem\root1\Readme. </p><p>　　You can manage the

71、 root directories that are available by choosing MIDlet > External events from the emulator window's menu. You'll see a small utility window for adding and removing roots. These actions will also generate even

72、ts for a registered listener object. </p><p>　　In a real device, personal information might be stored in a proprietary </p><p>　　format in memory. The emulator uses a directory on your hard disk

73、 to </p><p>　　contaiin this information, accessible using the PIM API. All information is stored in <toolkit>\appdb\pim. Lists are stored in subdirectories of the contacts, events, and todo directories

74、. For example, a contact list called Contacts is contained in <toolkit>\ appdb\ pim\ contacts\ Contacts. </p><p>　　Inside the list directory, items are stored in standard formats specified by the Inter

75、net Mail Consortium. Contacts are stored in vCard format, while calendar and to-do items are both stored in vCalendar format. </p><p><b>　　Summary</b></p><p>　　The J2ME Wireless Tool

76、kit 2.2 is much more than an incremental update of an excellent tool.It includes support for four exciting new specifications that together define six new APIs. As the world of wireless Java technology rapidly evolves, t