Oracle

Java, the leading embedded platform, is a trusted, proven platform ideally suited to embedded systems where security and reliability are critical. Java's modular architecture and efficient language lower costs by shortening development time and easing maintenance requirements. Unparalleled industry support delivers broad availability of partner technologies, ongoing innovation, and prevents proprietary lock-in, while software's largest base of developers ensures ready staffing.

• More than three billion devices are powered by Java technology
• One billion Java downloads each year
• 80% of mobile developers target the Java platform
• More than 150 million Java-based TV devices have been deployed
• Over 8 billion Java Card units have been shipped since its introduction

Simply put, Java makes embedded systems safer, more reliable, and easier to develop.

Java Optimizations for ARM

Oracle and ARM have collaborated extensively to deliver outstanding performance of both Java ME and Java SE on ARM architecture microprocessors. As of July, 2011, Oracle releases fully optimized Java SE Embedded builds for ARM at launch of each update.

Optimizations for ARM provided in recent Oracle Java SE Embedded releases include:

• Dynamic detection of which CPU variant the JVM is running on to use ARMv6/ARMv7 instructions when available
• Optimized synchronization code depending on whether we are running on uniprocessor
• Multi-core support including parallel garbage collection and background JIT compilation
• Reduced static and dynamic footprint
• Server (C2) Just-in-Time compiler support targeting performance improvements for traditional server applications
• Hand-coded memcpy, array copy routines
• Dynamic floating point detection for VFPv3 D16, D32 CPUs
• Software floating point support for non VFP CPUs

Future optimizations under consideration include: 

• Hardfloat binaries (instead of VFP using softfp)
• Thumb2 compiled binaries - typically reduces the size of the binaries by 21%
• Tiered Compilation - improves startup of Server VM by using Client JIT initially, Server JIT will optimize frequently used methods post startup        
• G1 Garbage Collector (Garbage First)

In September 2012, Oracle announced a new product in its Java Platform, Micro Edition (Java ME) product portfolio, Oracle Java ME Embedded a complete client Java runtime designed and optimized to meet the unique requirements of small embedded, low power devices such as micro-controllers and other resource-constrained hardware without screens or user interfaces.

This release brings a commercial implementation of Java for small footprint devices based on the ARM architecture, including the Cortex -M and Cortex-A processor families. Features include:

• On-the-fly application downloads and updates
• Remote operation, often in challenging environments
• Ability to add new capabilities without impacting the existing functions
• Support for hardware with as little as 130 kB RAM and 350 kB ROM