Java Question Shared objects

[HotShoe]

My background is in C, Assembly, Pascal, and now b4a. I can read and understand java source, but I don't know java. I have developed libraries, and done kernel development for Android and Linux for many years.

My question is can b4a use shared object libraries written in C like system libraries and such? My understanding is that java can access .so files in the system, but is there a way that I can use my own IMAP and other libraries in b4a?

I have the Android ported .jar files for java.mail, but I have no luck trying to wrap them to get to the IMAP functionality. If I can include my own .so file in the package and access those routines, my problem is solved since I know these routines and exactly how and when to call them.

Adding a reference in the manifest is simple enough, so the only remaining obstacle is getting b4a to see and use that shared object.

Thanks,

--- Jem

Missing Link Software
Oklahoma City, OK.

 

[Erel]

You can use Java libraries that access so libraries. SQLCipher for example uses multiple native libraries.

I recommend you to create a small program in Eclipse that uses your library. Once it is working (not a simple task!) I can help you do the changes requires in order to access it from Basic4android.

 

[HotShoe]

Libs

Thanks Erel,

I know a few java programmers that I will ask to help with that. I have a mail client written that is lacking support for IMAP, NNTP, and Exchange. I do have the ported java .jar (or source) files that support IMAP and I believe NNTP (will have to check).

Wrapping those files seems straight forward (according to one of the java guys), but I do have another question. Do I need to include those files in the .apk file or does b4a import the libs itself? Also, can I create a lib directory in the project's files directory and have b4a pack the contents of that directory at compile time?

Thanks,

--- Jem

Missing Link Software
Oklahoma City, OK.

 

[Erel]

You will need to include the so libs in the APK file and then copy them (if they do not exist) to File.DirInternal and call System.load to load them.

See the SQLCipher tutorial. It should be helpful.