Using SDK to develop mobile phone (Java) or not?

Recently, I have to use java to develop mobile phones. I plan to develop on the following brands:

NOKIA

Samsung

Sony Ericsson

Motorola

LG

I visited the "developer website" of each company. It seems that they have provided their own SDK for J2me development

I am new to this field. I have several questions:

>Since they all support the Java platform, why do we need an additional Java SDK? > Can I benefit from the SDK? > What determines whether I should use the SDK?

Solution

It all depends on the complexity of the application you want to develop

Developing a basic application to run on many different phones is feasible, but the complexity will grow exponentially with each advanced feature you add, especially if you want to locate existing, old and upcoming devices

You also need to consider that each manufacturer can support multiple operating systems and platforms

Nokia has series40 (3rd and 5th Editions), Series60 (2nd, 3rd and 5th Editions) and series80

Samsung has at least two major versions of its own platform and the last two versions of series 60

Sony Ericsson has three major versions of JP8 platform (and jp7), series 60 version 5, and UIQ 2 X and UIQ 3 x

Series80,Series60,UIQ 2. X and UIQ 3 X is based on Symbian operating system Different versions of Symbian OS use different JVMs, and several companies provide JSR implementations

Motorola has at least two major versions of its own platform and several UIQ devices

The main problem of J2ME is fragmentation For various reasons (good or bad, technical or commercial), the Java promise of "write once, run anywhere" is considered completely unfulfilled in the mobile industry

If you want the same code to run on many platforms at the same time, you need to code many functions in a platform specific manner

Many J2ME platforms also add non-standard APIs, properties, configuration, "bugs"

Most importantly, the manufacturer's SDK should allow debugging or MIDlet deployment on the device via USB They provide basic or extended tools to help test on devices, because this is an area that usually lacks a general WTK

Probably, yes OK, so most of them can only run on Windows desktop computers, but the SDK itself should be free

Start with WTK When you realize that you are trying to do something specific to the mobile phone manufacturer, please get the corresponding SDK

An example: the WTK pdapdemo sample application contains a basic file system browser It shows very different results on different platforms

As Pavel alexeev suggested, DEVICEANYWHERE is a good tool, assuming you have an appropriate test budget Nokia offers something similar, but it is obviously limited to Nokia phones