Programming Wireless Devices with the J2ME Platform (Java) [Paperback]

This book is designed specifically for those people who are interested in writing Java applications for the J2ME / MIDP platform (the Mobile Information Device Profile). If that is what you are interested in, this should be the only book you need.

With the proliferation of MIDP enabled handset all over the world, more and more people will want to write applications for those devices. This book will have you writing those applications in no time.

Unlike some of the other J2ME related books that have been rushed to press recently, this doesn't attempt to cover all things regarding programming small devices. It assumes a basic Java literacy, has a brief introduction to MIDP, and then jumps straight into the details. There is no hand-holding, no padding, just the details of the APIs, how to use them, and intelligent examples.

Particularly well written is the section on User Interface development using the javax.microedition.lcdui libraries.

What this book isn't:
- It's not a "teach yourself J2ME in 5 minutes"
- An introducton to J2ME
- A tutorial on J2ME
- A guide to other J2ME technologies such as CDC
- A guide to wireless technologies like Bluetooth or 802.11b.

What it is:
- An intelligent, well written guide to programming MIDP.

If you want to write MIDP applications, this book is perfect for your needs. It "does exactly what it sez on the tin".

Trouble is that these devices are all different. There are at least two different major operating systems on the PDA's and what the OS-situation is for the mobile phones can be difficult to tell. Even having the same operating system is not enough as the hardware platforms are different. This can certainly complicate the life of a developer. Choose your platform, mate!

Unless JAVA is used, of course! The promised land of Code Once, Run Everywhere cannot completely be fullfilled (we know!), but in the world of small devices there now exist a set of standards. These have acronyms such as CLDC and MIDP and are found within the Micro Edition of the JAVA environment (J2ME).

This book describes at a good level the J2ME-platform. The focus is placed mostly on the MIDP libraries which is natural as it is here that the most functions are found. The book covers the available API calls in a good way: Not too detailed, but clear and with a lot of example code. The authors remember to include proper warnings against misuse of some of the library routines - do not overdo the vibrator or flashing background, remember to add commands so that the user can navigate: That sort of advice. And trivial as this may seem, it is still needed, because programming an embedded or wireless device is something completely different than coding a PC-based application.

Between the release of the first edition of the book and this there has been a rapid development within the J2ME area, especially when it comes to the MIDP-platform. A host of new API's has been added to MIDP and this is clearly marked in the book. This is of course helpfull if you have older books and wants to compare. Or if you want to promote the new stuff - else I find it unnecessary.

The book is mostly concerned with the MIDP API and as such does not cover much outside of this scope. You will look in vain for a description of the JSR-82 BlueTooth specifications or the WiFi-protocols. This, I feel, is a weakness because of the growing impact of such network technologies.

The book itself is platform-independent: While it shows many examples it does not show how to compile and deploy an application to a specific wireless device, much less discuss existing platforms. It is an introduction to the CLDC and MIDP API's, not to the development process itself. But the book is important for a good introduction to programming in the "small world" and is a must for the developer. The starting chapters also give a good overview of the position of the J2ME environment and its components and should be required reading for any JAVA evangelist and architect.