I have been doing a lot of work to create a JavaME version of our JPedal PDF viewer, so I thought some observations might be interesting.
On a positive note, the thing that struck me was how complete the top end version of JavaME is. In particular, support for the Graphics2D object means you can build some fairly sophisticated applications for mobile devices. What is missing is some of the finer functionality such as the ability to convert between ColorSpaces. That said, there is usually an alternative.
The biggest aspect of JavaME I have found is its adaptability with the use of add ons, the biggest head ache for most developers is figuring out which extra jar’s, ie packages are needed for the functionality you need.
another issue you will need to handle is File Handling as JavaME has no JFileChooser for example, you can open files but you have to manually key in the location of the file you want, or add a custom file browser to locate the file you want.
JavaME’s top end version is so close the JavaSE but lacks those tiny details that pdfs have so many of i.e. different colorspaces for all the different image types which are supported in PDF files, this makes converting a PDF library to work on JavaME quite a challenge. Indeed if you are prepared to invest that much effort in it may be worth porting the code to GWT(google web toolkit) or Android instead.
Java ME has 2 real issues at the moment,
1 – with Oracle promising to merge SE and ME, does ME have a future?
2 – more for the mobile community, will SE work on the majority of mobile phones in the market, with only half of JavaME’s current structure working on current mobile phones.
What do you think about this?