Introduction to EPOC Java Development
by Richard Bloor
One of the challenges presented by the current array of wireless devices is that programming can involve the use of proprietary languages, with all their obvious drawbacks.
This was true of EPOC until 1999. Up to that date the developer had two choices for creating portable applications, OPL and C++. Both these are proprietary languages, OPL in the true sense, and C++ because all the underlying EPOC classes are proprietary (even though the language is standard). However with the release of EPOC R5 in 1999 Symbian made a JVM for Java 1.1.2 available.
Since then Symbian have been signalling that they expect Java to become the primary EPOC development tool with C++ being used only by specialist developers requiring optimum performance.
Symbian are aggressively developing EPOC Java abilities. This is illustrated by their reference implementation of Javaphone. In addition, individual licensees are working to enhance their Java support as witnessed by the Psion agreement with Pointbase the Java Database supplier and Espital.
Developing Java for EPOC devices is both familiar (just go write some Java) and unfamiliar (allowances have to be made for screen size, system resources, look and feel and the EPOC application launching mechanisms). In this article we will look at the special considerations that need to be taken in developing Java for EPOC.
The most unfamiliar aspect of developing Java for EPOC is the process associated with running and installing an application. Examination of these processes will form the core of this training article.
The two tools essential for developing Java for EPOC are the Symbian Java SDK and a Java development environment for Java 1.1.x. The EPOC Java SDK can be obtained by either:
- registering on the Symbian Developer Network and download the SDK. (You can also order the SDKs on CD-ROM from Symbian for a small handling charge.) or
- purchasing the Wrox press book Professional Symbian Programming which comes with a CD containing all four SDKs (the fourth being the EPOC Connect SDK for PC connectivity development).
The Wrox book contains a chapter on Java, but mainly concentrates on C++ and is therefore probably not worthwhile unless you also have an interest in C++ or JNI development. Even if you buy the book registering on Symbian's developer network is worthwhile as the site contains a number of other useful resources, including Java knowledgebase, white papers, additional examples and extension classes.
The SDK contains an emulator that includes all the standard EPOC functionality and applications and simulation of 1/2 VGA (640x240), full VGA (640x480) and large (800x600) EPOC screens. This is accompanied by full documentation, some example programs and the utilities for creating program icons, application and installation files.
To run the SDK you will require a Pentium PC running Windows 95 or above and about 45MB of free space.
(Incidentally the SDK also provides an excellent free route to evaluate the core EPOC applications if you were thinking of buying an EPOC machine.)
Next: EPOC Java Fundamentals