Let’s say you want to modify java applications by yourself using your phone? Here are the prerequisites to change name, icons etc of the java applications (ie, Opera Mini, etc.).
1. X-Plore 1.42 : This is a File Manager that is used to extract jar (j2me) archives and edit manifest.mf files.
2. Zntxhan 2.04 : This is a File Editor that is used to edit files with .class extension and also other files.
3. Image Designer 1.40 : Image Editor that is used to edit or create image files for icons, skins and etc of a java file.
4. JarBoom 2.0 : Compiler that is used to compile or pack the extracted java archive.
We will now start on the basic of modding.
1. Preparing the java file:
Lets say we want to modify an Opera Mini 5 final, all we have do is use xplore to locate it(opera mini), click it and we see a lots of files, then mark and extract all files in the operamini to JarBoom ‘s unjar folder using X-plore.
2. Editing the Manifest:
Look for META-INF folder and inside you will see a MANIFEST.MF file. You can edit it with X-Plore by pressing [8 ]. Edit the necessary details you want to change (ie, MIDlet-Vendor, MIDlet- Version, MIDlet-Name, MIDlet-Info- URL, MIDlet-Description and MIDlet-1). Make sure when saving, the Save as unicode option is NOT checked. You can change the midlet name and midlet-1 name to your name so that the application now bears you name.
3. Editing the Class Files:
Using Zntxhan, locate any .class file via Listway. We need to edit these to change the server and put a trick on it. In Opera Mini 5 final the server is located in f.class (this differs on every java apps). You can use the functions of Zntxhan to search for the string of the server in the class. After editing, save and delete the created .class_bak (which serves as backup but we do not need this)
4. Editing the Icon:
Here we will use ImageDesigner, you can edit the i.png file that was extracted to any design you like, just make sure you made it small to fit in as an icon, lets say 50×50 pixelis.
5. Compiling: After we had edited what we needed to, we ‘ re off to compiling the files back into jar file again. In this case, we will use JarBoom, choose Tools-Compile and locate the manifest.mf inside meta- inf folder and give name to your jar file, wait until the packing completes.
That’s it! Try your modded opera mini, if it works, you’ve done your first mod, but if not, go through this post again.