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Java Platform, Micro Edition, or Java ME, is a Java platform designed for embedded systems (mobile devices are one kind of such systems). Target devices range from industrial controls to mobile phones (especially feature phones) and set-top boxes. Java ME was formerly known as Java 2 Platform, Micro Edition (J2ME). Java ME was designed by Sun Microsystems, acquired by Oracle Corporation in 2010; the platform replaced a similar technology, PersonalJava. Originally developed under the Java Community Process as JSR 68, the different flavors of Java ME have evolved in separate JSRs. Sun provides a reference implementation of the specification, but has tended not to provide free binary implementations of its Java ME runtime environment for mobile devices, rather relying on third parties to provide their own. As of 22 December 2006, the Java ME source code is licensed under the GNU General Public License, and is released under the project name phoneME. As of 2008, all Java ME platforms are currently restricted to JRE 1.3 features and use that version of the class file format (internally known as version 47.0). Should Oracle ever declare a new round of Java ME configuration versions that support the later class file formats and language features, such as those corresponding to JRE 1.5 or 1.6 (notably, generics), it will entail extra work on the part of all platform vendors to update their JREs. Java ME devices implement a ''profile''. The most common of these are the Mobile Information Device Profile aimed at mobile devices, such as cell phones, and the Personal Profile aimed at consumer products and embedded devices like set-top boxes and PDAs. Profiles are subsets of ''configurations'', of which there are currently two: the Connected Limited Device Configuration (CLDC) and the Connected Device Configuration (CDC).〔(Java ME Technology )〕 There are more than 2.1 billion Java ME enabled mobile phones and PDAs.〔(About Java )〕 It is popular in sub $200 devices such as Nokia's Series 40. It was also used on the Bada operating system and on Symbian OS along with native software. Also, there are implementations for Windows CE, Windows Mobile, Maemo, MeeGo and Android available for separate download.〔(phoneME for Windows CE, Windows Mobile and Android (development stopped in 2011-06-15) )〕〔(App Runner (development stopped in 2010-05-11) )〕 == Connected Limited Device Configuration == (詳細はConnected Limited Device Configuration (CLDC) contains a strict subset of the Java-class libraries, and is the minimum amount needed for a Java virtual machine to operate. CLDC is basically used for classifying myriad devices into a fixed configuration. A configuration provides the most basic set of libraries and virtual-machine features that must be present in each implementation of a J2ME environment. When coupled with one or more profiles, the Connected Limited Device Configuration gives developers a solid Java platform for creating applications for consumer and embedded devices. The configuration is designed for devices with 160KB to 512KB total memory, which has a minimum of 160KB of ROM and 32KB of RAM available for the Java platform. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Java Platform, Micro Edition」の詳細全文を読む スポンサード リンク
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