Embedding Knopflerfish in Android doesn't work

Question

I am trying to embed the Knopflerfish framework into an android application to load and unload bundles dynamically. I followed this tutorial

The first step I did is to download framework.jar frome this link, and to add it to my class path in my eclipse project.

Additionally, below is my onCreate() method:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);



    Map fwprops = new Hashtable(); //CHANGED
    // add any framework properties to fwprops
    FrameworkFactory ff = new FrameworkFactoryImpl();
    mFramework = ff.newFramework(fwprops);
    try {

        mFramework.init(); //ERROR HERE!!

    } catch (BundleException be) {
        // framework initialization failed

        Log.d(TAG, be.getStackTrace().toString());
    }



}

Note that I changed one line of the code, because it shows a syntax error.

Which is:

Dictionary fwprops = new Hashtable();
to
Map fwprops = new Hashtable(); //CHANGED

The Syntax Error: The method newFramework(Map) in the type FrameworkFactory is not applicable for the arguments (Dictionary)

Now, According to @ldx in this post, "The patches I submitted for better Android/Dalvik support in Knopflerfish have been merged so patching and recompiling KF should not be necessary anymore:"

and therefore I didn't add anything assuming my code is enough as it is now.

When I run the app. I instantly get: Unfortunately, Knopflerfish_Android has stopped on the screen.

Can someone help? Below is the LogCat:

08-04 18:25:35.233: E/Trace(7018): error opening trace file: No such file or directory (2)
08-04 18:25:36.793: D/AndroidRuntime(7018): Shutting down VM
08-04 18:25:36.793: W/dalvikvm(7018): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
08-04 18:25:36.813: E/AndroidRuntime(7018): FATAL EXCEPTION: main
08-04 18:25:36.813: E/AndroidRuntime(7018): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.knopflerfish_android/com.example.knopflerfish_android.MainActivity}: java.lang.RuntimeException: Failed to initialize storage org.knopflerfish.framework.bundlestorage.file.BundleStorageImpl
08-04 18:25:36.813: E/AndroidRuntime(7018):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at android.app.ActivityThread.access$600(ActivityThread.java:141)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at android.os.Handler.dispatchMessage(Handler.java:99)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at android.os.Looper.loop(Looper.java:137)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at android.app.ActivityThread.main(ActivityThread.java:5041)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at java.lang.reflect.Method.invokeNative(Native Method)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at java.lang.reflect.Method.invoke(Method.java:511)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at dalvik.system.NativeStart.main(Native Method)
08-04 18:25:36.813: E/AndroidRuntime(7018): Caused by: java.lang.RuntimeException: Failed to initialize storage org.knopflerfish.framework.bundlestorage.file.BundleStorageImpl
08-04 18:25:36.813: E/AndroidRuntime(7018):     at org.knopflerfish.framework.FrameworkContext.init(FrameworkContext.java:343)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at org.knopflerfish.framework.SystemBundle.doInit(SystemBundle.java:513)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at org.knopflerfish.framework.SystemBundle.init(SystemBundle.java:125)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at com.example.knopflerfish_android.MainActivity.onCreate(MainActivity.java:39)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at android.app.Activity.performCreate(Activity.java:5104)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
08-04 18:25:36.813: E/AndroidRuntime(7018):     ... 11 more
08-04 18:25:36.813: E/AndroidRuntime(7018): Caused by: java.lang.reflect.InvocationTargetException
08-04 18:25:36.813: E/AndroidRuntime(7018):     at java.lang.reflect.Constructor.constructNative(Native Method)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at java.lang.reflect.Constructor.newInstance(Constructor.java:417)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at org.knopflerfish.framework.FrameworkContext.init(FrameworkContext.java:341)
08-04 18:25:36.813: E/AndroidRuntime(7018):     ... 17 more
08-04 18:25:36.813: E/AndroidRuntime(7018): Caused by: java.lang.RuntimeException: Cannot create directory: /fwdir/bs
08-04 18:25:36.813: E/AndroidRuntime(7018):     at org.knopflerfish.framework.Util.getFileStorage(Util.java:99)
08-04 18:25:36.813: E/AndroidRuntime(7018):     at org.knopflerfish.framework.bundlestorage.file.BundleStorageImpl.<init>(BundleStorageImpl.java:127)
08-04 18:25:36.813: E/AndroidRuntime(7018):     ... 20 more
08-04 18:25:39.543: I/Process(7018): Sending signal. PID: 7018 SIG: 9

Answer 1

At the comment // add any framework properties to fwprops, I only had to add the Framework launching property specifying the persistent storage directory used by the framework. Since it is Android, the default value for the storage directory doesn't seem to work. Instead, I should specify the directory under sdcard. Hence, I added this line:

 fwprops.put("org.osgi.framework.storage", "sdcard/fwdir");

Below is my updated code:

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Map<String, String> fwprops = new Hashtable<String, String>(); //CHANGED

        // add any framework properties to fwprops
        fwprops.put("org.osgi.framework.storage", "sdcard/fwdir");

        FrameworkFactory ff = new FrameworkFactoryImpl();
        mFramework = ff.newFramework(fwprops);

        try {

            mFramework.init(); //THIS WORKS NOW :P :P

        } catch (BundleException be) {
            // framework initialization failed

            Log.d(TAG, be.getStackTrace().toString());

        }

    }  

Thanks to these two links: http://www.osgi.org/javadoc/r4v43/core/org/osgi/framework/Constants.html#FRAMEWORK_STORAGE http://www.knopflerfish.org/releases/current/docs/bundledoc/index.html?docpage=framework/index.html