[android-developers] Re: How to integrate c code with java code
To Amit :
To interaction between C and Java maybe a little complicate, you can do it
follows this:
*Because each class loader maintains a set of native libraries, the
programmer may use a single library to store all the native methods needed
by any number of classes as long as those classes have the same defining
loader. *
*Native libraries will automatically be unloaded by the virtual machine when
their corresponding class loaders are garbage collected.*
it a example
JNIEXPORT jstring JNICALL Java_Prompt_getLine
(JNIEnv *env, jobject obj, jstring prompt)
{
char buf[128];
const char *str = (*env)-GetStringUTFChars(env, prompt, 0);
printf(%s, str);
(*env)-ReleaseStringUTFChars(env, prompt, str);
}
I just writed a document about this, but sorry it is a Chinese version, i
will post it after tranlate to English
2008/12/2 Amit [EMAIL PROTECTED]
Android supports JNI at application framework level.
For example, in platform/frameworks/base.git, Mediaplayer.java at:
http://android.git.kernel.org/?p=platform/frameworks/base.git;a=blob;f=media/java/android/media/MediaPlayer.java;h=b6064e1bb6b0f40f72fc1535b264f5c3fa190548;hb=HEAD
file has got some native function calls
And these native function calls must be implemented in either
libmedia_jni.so or media_jni.dll
but i'm unable to located either of the files in the source code. plz
tell me the path if they are present in the source code.
i found a c++ file android_media_MediaPlayer.cpp at:
http://android.git.kernel.org/?p=platform/frameworks/base.git;a=blob;f=media/jni/android_media_MediaPlayer.cpp;h=f9f3646f0c308bf19bb3c3af02fc0e0e4260afbd;hb=HEAD
that implements the corresponding native functions,
but coudnt find how it calls the actual c/c++ libraries. Also, it
includes files media/mediaplayer.h which i coudnt find.
This must be the file generated by java file using javah.
It also included files JNIHelp.h and android_runtime/AndroidRuntime.h
which are also untraceable.
Plz help me in this problem.
Thanks
Amit
On Dec 1, 2:07 pm, [EMAIL PROTECTED] [EMAIL PROTECTED]
wrote:
Hi Amit,
DigitalAirways (www.digitalairways.com) does this to allow all the
Kaleido applications to run on Android with great performances and
very limited porting effort.
Franck
On Nov 28, 11:00 am, Amit [EMAIL PROTECTED] wrote:
Hello friends,
Can u plz tell that if i want to write some piece of code for android
in c or c++, how can i integrate the code with java code.
Any help appreciated
Thanks
Amit- Hide quoted text -
- Show quoted text -
--
Best Regards
Eric Chan
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[android-developers] Re: How to integrate c code with java code
Android supports JNI at application framework level. For example, in platform/frameworks/base.git, Mediaplayer.java at: http://android.git.kernel.org/?p=platform/frameworks/base.git;a=blob;f=media/java/android/media/MediaPlayer.java;h=b6064e1bb6b0f40f72fc1535b264f5c3fa190548;hb=HEAD file has got some native function calls And these native function calls must be implemented in either libmedia_jni.so or media_jni.dll but i'm unable to located either of the files in the source code. plz tell me the path if they are present in the source code. i found a c++ file android_media_MediaPlayer.cpp at: http://android.git.kernel.org/?p=platform/frameworks/base.git;a=blob;f=media/jni/android_media_MediaPlayer.cpp;h=f9f3646f0c308bf19bb3c3af02fc0e0e4260afbd;hb=HEAD that implements the corresponding native functions, but coudnt find how it calls the actual c/c++ libraries. Also, it includes files media/mediaplayer.h which i coudnt find. This must be the file generated by java file using javah. It also included files JNIHelp.h and android_runtime/AndroidRuntime.h which are also untraceable. Plz help me in this problem. Thanks Amit On Dec 1, 2:07 pm, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote: Hi Amit, DigitalAirways (www.digitalairways.com) does this to allow all the Kaleido applications to run on Android with great performances and very limited porting effort. Franck On Nov 28, 11:00 am, Amit [EMAIL PROTECTED] wrote: Hello friends, Can u plz tell that if i want to write some piece of code for android in c or c++, how can i integrate the code with java code. Any help appreciated Thanks Amit- Hide quoted text - - Show quoted text - --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
[android-developers] Re: How to integrate c code with java code
I want to know that if i write some piece of code in any languagge may be C or even Java, how can i integrate it in android SDK. How can it be called like other android APIs. For example, if i write some framework like video playback frame work in any language, how can it be integrated with android framework so that applications can make use of it like other APIs. Are there any specifications for such code to be written. If it cant be done this way, can u tell me if there is a way possible for me to integrate it with my local SDK so that my applications can make use of it. Does eclipse provide any help in integratiing such source code. Any Help Appreciated Thanks Regards Amit On Nov 28, 10:38 pm, Robert Green [EMAIL PROTECTED] wrote: You can't. The device will only run java using the supplied API. On Nov 28, 4:00 am, Amit [EMAIL PROTECTED] wrote: Hello friends, Can u plz tell that if i want to write some piece of code for android in c or c++, how can i integrate the code with java code. Any help appreciated Thanks Amit- Hide quoted text - - Show quoted text - --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
[android-developers] Re: How to integrate c code with java code
Hi Amit, DigitalAirways (www.digitalairways.com) does this to allow all the Kaleido applications to run on Android with great performances and very limited porting effort. Franck On Nov 28, 11:00 am, Amit [EMAIL PROTECTED] wrote: Hello friends, Can u plz tell that if i want to write some piece of code for android in c or c++, how can i integrate the code with java code. Any help appreciated Thanks Amit --~--~-~--~~~---~--~~ You received this message because you are subscribed to the Google Groups Android Developers group. To post to this group, send email to android-developers@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/android-developers?hl=en -~--~~~~--~~--~--~---
