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24-426: Java Platform, Micro Edition or Java ME is a computing platform for development and deployment of portable code for embedded and mobile devices (micro-controllers, sensors, gateways, mobile phones, personal digital assistants, TV set-top boxes, printers). Java ME was formerly known as Java 2 Platform, Micro Edition or J2ME . The platform uses the object-oriented Java programming language, and

48-837: 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). In 2008, Java ME platforms were restricted to JRE 1.3 features and use that version of

72-505: A web browser . As long as it is a required component for the program code to execute, it is part of the computing platform. Platforms may also include: Some architectures have multiple layers, with each layer acting as a platform for the one above it. In general, a component only has to be adapted to the layer immediately beneath it. For instance, a Java program has to be written to use the Java virtual machine (JVM) and associated libraries as

96-576: A basic 2D gaming API. Applications written to use this profile are called MIDlets . Many cell phones come with a MIDP implementation, and it is a popular platform for downloadable cell phone games. The Information Module Profile is specified in JSR 195 and is designed for vending machines , network cards, routers, telephone boxes and other systems with either simple or no display and some form of limited two way network access. Only APIs for application creation, storage, and network access are defined. These are

120-504: A now-abandoned reference implementation under the name phoneME . Operating systems targeting Java ME have been implemented by DoCoMo in the form of DoJa , and by SavaJe as SavaJe OS. The latter company was purchased by Sun in April 2007 and now forms the basis of Sun's JavaFX Mobile . The open-source Mika VM aims to implement JavaME CDC/FP, but is not certified as such (certified implementations are required to charge royalties, which

144-588: A platform but does not have to be adapted to run on the Windows, Linux or Macintosh OS platforms. However, the JVM, the layer beneath the application, does have to be built separately for each OS. Connected Limited Device Configuration The Connected Limited Device Configuration ( CLDC ) is a specification of a framework for Java ME applications describing the basic set of libraries and virtual-machine features that must be present in an implementation. The CLDC

168-552: 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. Designed for mobile phones, the Mobile Information Device Profile includes a GUI , and a data storage API, and MIDP 2.0 includes a basic 2D gaming API . Applications written for this profile are called MIDlets . JSR 271: Mobile Information Device Profile 3 (Final release on Dec 9, 2009) specified

192-610: 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

216-632: A subset of the javax.microedition.io, rms and midlet packages in MIDP. Siemens Mobile and Nokia put forward this specification to the JCP. The DoJa profile was designed for the i-mode mobile phone by NTT DoCoMo . The Digital Set Top Box profile, specified in JSR 242, is designed for the cable market. Also referred to as OnRamp , this profile is based on a subset of the OpenCable Application Platform ( OCAP ), which defines

240-452: Is a strict subset of MIDP 1.0 except that it does not include user interface APIs — in other words, it does not include support for the Java package javax.microedition.lcdui . JSR-228, also known as IMP-NG, is IMP's next generation that is based on MIDP 2.0, leveraging MIDP 2.0's new security and networking types and APIs, and other APIs such as PushRegistry and platformRequest() , but again it does not include UI APIs, nor

264-483: Is combined with one or more profiles to give developers a platform for building applications on embedded devices with very limited resources such as pagers and mobile phones . The CLDC was developed under the Java Community Process as JSR 30 (CLDC 1.0) and JSR 139 (CLDC 1.1). CLDC is designed for devices that have limited processing power, memory, and graphical capability. Devices typically have

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288-523: Is impractical for an open-source project). Consequently, devices which use this implementation are not allowed to claim JavaME CDC compatibility. The Linux-based Android operating system uses a proprietary version of Java that is similar in intent, but very different in many ways from Java ME. There are other emulators, including emulators provided as part of development kits by phone manufacturers, such as Nokia, Sony-Ericsson , Siemens Mobile, etc. The Connected Limited Device Configuration (CLDC) contains

312-475: Is part of the Java software-platform family. It was designed by Sun Microsystems (now Oracle Corporation ) and replaced a similar technology, PersonalJava . In 2013, with more than 3 billion Java ME enabled mobile phones in the market, the platform was in continued decline as smartphones have overtaken feature phones. The platform used to be popular in feature phones, such as Nokia's Series 40 models. It

336-574: The 3rd generation Mobile Information Device Profile (MIDP3), expanding upon the functionality in all areas as well as improving interoperability across devices. A key design goal of MIDP3 is backward compatibility with MIDP2 content. The Information Module Profile (IMP) is a profile for embedded, "headless" devices such as vending machines, industrial embedded applications, security systems, and similar devices with either simple or no display and with some limited network connectivity. Originally introduced by Siemens Mobile and Nokia as JSR -195, IMP 1.0

360-533: The CLDC framework to provide a complete Java application environment. There are specific profiles for devices ranging from vending machines to set-top boxes, with the mobile phone profile MIDP being the most prevalent. The Mobile Information Device Profile is a profile designed for cell phones. There are two versions of MIDP available, specified in JSR 37 (MIDP 1.0) and JSR 118 (MIDP 2.0). Both versions provide an LCD oriented GUI API, with MIDP 2.0 including

384-718: The additional profiles supported. This specification was developed under the Java Community Process. The Personal Basis Profile extends the Foundation Profile to include lightweight GUI support in the form of an AWT subset. This is the platform that BD-J is built upon. The ESR consortium is devoted to Standards for embedded Java. Especially cost effective Standards. Typical applications domains are industrial control, machine-to-machine, medical, e-metering, home automation , consumer, human-to-machine-interface, ... Computing platform Sometimes,

408-416: The base class library due to restrictions on reflection usage. All java.lang.* classes which normally implement Serializable do not, therefore, implement this tagging interface . Other examples of limitations depend on the version being used, as some features were re-introduced with version 1.1 of CLDC. A profile is a set of APIs that support devices with different capabilities and resources within

432-542: The class file format (internally known as version 47.0). Oracle provides a reference implementation of the specification, and some configurations and profiles for MIDP and CDC. Starting with the JavaME 3.0 SDK, a NetBeans -based IDE supported them in a single IDE. In contrast to the numerous binary implementations of the Java Platform built by Sun for servers and workstations, Sun tended not to provide binaries for

456-553: The following features: Compared to the Java SE environment, several APIs are absent entirely, and some APIs are altered such that code requires explicit changes to support CLDC. In particular, certain changes are not just the absence of classes or interfaces, but actually change the signatures of existing classes in the base class library. An example of this is the absence of the Serializable interface, which does not appear in

480-506: The game API. The Connected Device Configuration is a subset of Java SE , containing almost all the libraries that are not GUI related. It is richer than CLDC. The Foundation Profile is a Java ME Connected Device Configuration (CDC) profile. This profile is intended to be used by devices requiring a complete implementation of the Java virtual machine up to and including the entire Java Platform, Standard Edition API. Typical implementations will use some subset of that API set depending on

504-413: The most relevant layer for a specific software is called a computing platform in itself to facilitate the communication, referring to the whole using only one of its attributes – i.e. using a metonymy . For example, in a single computer system, this would be the computer's architecture , operating system (OS), and runtime libraries . In the case of an application program or a computer video game ,

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528-485: The most relevant layer is the operating system, so it can be called a platform itself (hence the term cross-platform for software that can be executed on multiple OSes, in this context). In a multi-computer system, such as in the case of offloading processing, it would encompass both the host computer's hardware , operating system (OS), and runtime libraries along with other computers utilized for processing that are accessed via application programming interfaces or

552-615: The platforms of Java ME targets, and instead relied on third parties to provide their own. The exception was an MIDP 1.0 JRE (JVM) for Palm OS. Sun provides no J2ME JRE for the Microsoft Windows Mobile (Pocket PC) based devices, despite an open-letter campaign to Sun to release a rumored internal implementation of PersonalJava known by the code name "Captain America". Third party implementations are widely used by Windows Mobile vendors. At some point, Sun released

576-479: Was also supported on the Bada operating system and on Symbian OS along with native software. Users of Windows CE , Windows Mobile , Maemo , MeeGo and Android could download Java ME for their respective environments ("proof-of-concept" for Android). Originally developed under the Java Community Process as JSR 68, the different flavors of Java ME have evolved in separate JSRs. Java ME devices implement

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