Embedded Java

This article has multiple issues. Please help improve it or discuss these issues on the talk page. It may require cleanup to meet Wikipedia's quality standards. Tagged since September 2011. Its introduction provides insufficient context for those unfamiliar with the subject. Tagged since September 2011. Its introduction may need to be rewritten to comply with Wikipedia's lead section guidelines. Tagged since September 2011. It needs to be updated. Tagged since September 2011.

[This section needs to be updated, as Embedded Java covers much more than Java ME and Sun SPOT alone—it also covers embedded use of Java on top of Java platforms such as JavaCard and Java SE ]

In discussions of Java ME specifications, such as the CDC/CLDC device capability sets and the MIDP profile definition, attention needs to be given to Embedded Java, which additionally requires very specialized, optimized JVMs, and the means to update the installed software and services such as OSGi.

Recent developments in the field are

• the Squawk Virtual Machine, a JVM developed by Sun Microsystems and deployed as part of Project Sun SPOT.
• the JPF line of products, based on JVMs developed by IS2T and deployed in collaboration with microcontrollers makers on several starter kits (AVR32, ARM7, ...)

The principal difference between Embedded Java and the several Java ME configurations is that the former is envisioned for use only in closed systems. That is, Embedded Java is for use in products that cannot be upgraded in the field. All of the Java code in these embedded systems is contained in flash memory. Thus the only class libraries that need to be present are the very methods and fields actually used by the Java application code; all the rest can be prestripped from the statically linked executable.

Java SE embedded

Java SE embedded is based on desktop Java Platform, Standard Edition.^[1] It is designed to be used on systems with at least 32 MB of RAM, and can work on Linux ARM, x86, or Power Architecture, and Windows XP and Windows XP Embedded architectures.

Java ME embedded

Java ME embedded is based on the Connected Device Configuration subset of Java Platform, Micro Edition.^[2] It is designed to be used on systems with at least 8 MB of RAM, and can work on Linux ARM, PowerPC, or MIPS architecture.

Licencing restrictions

Oracle impose Java license restrictions for some embedded application areas.^[3] This has caused legal disputes over the Java code within the Android mobile operating system.^[4]

See also

• GNU Compiler for Java
• Excelsior JET, Embedded Edition
• Sun SPOT Sun SPOT Project
• IS2T EDU Program
• Real-Time Specification for Java
• JamaicaVM

References

External links

• Java SE for Embedded : Java SE for Embedded technology from Oracle Corporation
• Java SE for Embedded Development Made Easy : Webcast covering development, troubleshooting, deployment
• http://www.systronix.com/ - Systronix TStik, JStamp, JStik  : Small embedded Java systems, some with deterministic/realtime capabilities
• Google Android project  : Open source project to create software for mobile devices such as the T-Mobile G1 phone
• JControl : Very compact Java Virtual Machine for Embedded Systems
• Mysaifu Java2 Virtual Machine
• MicroJvm : Real-time Java virtual machines for embedded systems
• Excelsior JET Embedded : Java SE 6 for embedded Linux and Windows, with AOT compiler
• http://www.parallax.com/ - Parallax's Javelin STAMP, similar to the Basic Stamp but utilizing object-oriented technology instead of Basic
• JamaicaVM : a cleanroom implementation of a virtual machine and build environment for running realtime and embedded Java programs.