- Release Date: 10 June, 2003
- Used Price: $38.63
- Availability: Usually ships within 24 hours
- Third Party Used Price: $31.75
Authors: Roger Riggs, Antero Taivalsaari, Jyri Huopaniemi, Mark Patel, James VanPeursem, Aleksi Uotila
Customer Rating: 3.86 of 5 (7 total reviews)
- Review of "Programming Wireless Devices with the J2ME"
So I have been programming with J2ME and DOJA for a while on various Japanese Cellphones. The Japanese cellphones that do support the full MIDP/CLDC combination do not yet support the MIDP 2.0 that this book is covering, but I thought it would be a good idea to check out what I might be able to use when they do, and also try and clear up my own confusion about what precisely the CLDC and MIDP actually are.
Having read the book I think I have a better idea of the distinction between CLDC and MIDP, but still don't feel wonderfully sure. The impression I come away with is that the CLDC is about ensuring a basic level of functionality and the MIDP describes a wider range of functionality such as GUIs and Advanced communications features. This would make sense then if the Japanese Docomo Java framework was CLDC and AU/Vodaphone framework was both CLDC and MIDP.
The book itself was reasonably informative as to the new MIDP 2.0 features, and I was interested to see some good code samples for things like the MIDP Game and Multimedia API - however the code samples don't yet appear available for download. I hope they'll be up soon so I can check them out.
Overall I found the book a little difficult to read - it is kind of more of a reference book - I would imagine myself dipping into it to get things I need, rather than reading through it to get an understanding of J2ME. In some ways the book would almost be better as a more condensed reference work. There are a number of good wireless programming tips such as making all communications run in a separate thread to improve user experience, but these are a little thin on the ground and the book is dominated by working through each detail of each of the APIs. I think is an important book to have if you are working against the MIDP2.0 specification, but I don't think I 'd recommend it to a beginner trying to learn J2ME.
I would imagine that successive iterations of this book will lead to major improvements, such as breaking the book into a Reference work, and a J2ME programming tips guide. I think another couple of years of explosive growth in J2ME wireless devices and programmers will make the latter work possible.
- Upgrade to MIDP 2 and CLDC 1.1
The market for small devices (cellphones, PDAs, watches,...) with computational ability, but much less so than a standard PC or laptop is potentially vast. No one disputes this. Its allure is enhanced by there being no overly dominant player hoovering up over 50% of the profits, like Microsoft and Intel collectively in PCs.
Logically, Sun sees growth here and this book is part of its frenetic rollout. It differs from the first edition because of significant upgrades to the 2 standards its describes. The Connected Limited Device Configuration (CLDC) went from version 1 in 1999 to 1.1 in 2002. It added more features that the book describes in detail. Basically, they give a richer compatibility with standard java (J2SE). The other standard, Mobile Information Device Profile (MIDP) went from version 1 to 2 in 2002. To developers the key additions were APIs for sound and games. In retrospect, MIDP 1 was indeed primitive, to lack these.
Commercially, the MIDP 2 changes in the book may be more important than the CLDC changes. It means that you can now develop games and other applications using sound, at a high enough level of abstraction that they can be run on a broader range of hardware. Well at least that is the idea. I have not done so. But the book's explanation seems logical and thorough enough to make this plausible. Undoubtedly, if you and others follow this path, gaps or insufficiencies will be found, leading to the next increments of the standards.
If you are still clutching the first edition of this book, or any other book that only covers CLDC 1 or MIDP 1, then drop it. Obsolete. Upgrade here.
- Needed when you want to code small
The focus on programming wireless devices is growing these years. New devices arrive every day, having a huge set of functions - you just want to play a game or get some music on these small gadgets. You could really use a pocket database or another type of application.
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.