This three-part series shows you how to get started creating Java ME Embedded applications for the Keil ARM Evaluation board. Two Oracle experts, Angela Caceido and Sungmoon Cho, demonstrate how to set up the evaluation board, install the Java ME binaries on the board, and then write and run a sample Java application on the evaluation board.
Type: Video
Released: 11.4 years ago
Intelligent devices are becoming an ever more important and ubiquitous part of our everyday lives. Mobile phones represented the first wave of smaller personal computers. And now, as the price of electronics and processing power continues to fall, there is an intersection between sensors and other electromechanical devices and computers that live on the edge of the Internet: close to the source of the data, processing the data locally and sending just what is required to other computers to consume. This wave of machine-to-machine (M2M) technology, or more broadly, the Internet of Things (IoT), is rapidly shaping the future of computing. Oracle Java Platform, Micro Edition (Java ME) provides Java developers with a direct path to this new market space by using their existing knowledge and skills.
The Raspberry Pi is a computer that is about the size of a deck of cards, yet it is capable of running a Linux distribution on its ARM 11 processor. The Raspberry Pi also supports USB, Ethernet, audio, HDMI, and RCA video output. But most importantly, the Raspberry Pi provides a 26-pin header that connects the computer to the outside world, through general-purpose input/output (GPIO) pins that can drive LEDs, read switches and other electronic signals, and connect to a wealth of inter-integrated circuit (I2C) devices, universal asynchronous receiver/transmitter (UART) devices, and more. This header and the Raspberry Pi's low cost is what makes the Raspberry Pi an ideal platform to develop real-world embedded applications with Java ME Embedded.
In this series of tutorials, learn how to write Java Embedded applications and how to create circuits and connect them to the Raspberry Pi to sense a change in a switch, light an LED, read the current temperature and barometric pressure, determine your location using a GPS device, and more!
For more information about Java Embedded, see the Java Embedded Documentation page.
Type: OBE
Released: 11 years ago
Java SE, both 7 and 8 are available for the Raspberry Pi (ARM 6 architecture), but what about Java EE and Web Services? How do I access devices using servlets and web services?
The answer is by combining two technologies. Recently, the Device I/O API has been under development as an Open JDK project - creating a standalone way to access the GPIO header using exactly the same API that makes Java ME Embedded so special. This allows developers to write DIO code outside of a Java ME Embedded VM.
The second technology is Java Embedded Suite 7.0. JES 7.0 is designed to run on ARM 6 and 7 environments and comes with a small footprint application server (Glassfish for Embedded Suite Application Server), Jersey RESTful Web Services Framework and Java DB Embedded database. GlassFish for Embedded Suite supports servlets 3.0, web services and bean validation.
Putting the two together, you can write a servlet or web service that controls and communicates with devices. In this article, I'll show you how to set up the JES 7.0 with DIO to turn an LED on and off using a servlet running on Oracle Java Embedded Suite on a Raspberry Pi.
Duration: 30 mins
Type: Article
Released: 10 years ago