I think you're confusing the JNI layer with the binder interface.
Binder is an interprocess-communication interface. JNI is an interface
between Java and native code.

In some cases JNI and binder interfaces are coincident, i.e. a JNI
interface translates directly into binder calls. In other cases, JNI
interacts with native code that runs in the application process. The
native code in turn might have a lower layer that interacts with a
binder service or directly with the kernel.

On Jan 7, 2:18 am, "martin d." <[email protected]> wrote:
> Hi Dianne,
>
> thanks for that quick reply. It helped guiding me in the right
> direction. Without any knowledge about JNI this is a bit hard to
> understand.
>
> Martin
>
> On Jan 6, 2:32 am, "Dianne Hackborn" <[email protected]> wrote:
>
> > It depends.  If you are calling on a proxy for a remote object (or an
> > IBinder that is implemented in native code), the transact() call on that
> > implementation is a native method so you go directly to native code (which
> > then talks with the driver to get the transaction to the other process).
> > This is in the BinderProxy class.  Otherwise, you are making a call on a
> > local object which has probably implemented transact() in Java code to
> > unmarshall the data and call the appropriate API on its interface.
>
> > On Mon, Jan 5, 2009 at 3:22 PM, martin d. <[email protected]> wrote:
>
> > > Hello,
>
> > > I am trying to understand some details about how IPC in Android works.
> > > I am stuck at the
> > > point where data is passed from "Java-world" to "native-world" (via
> > > JNI I guess).
>
> > > Could someone please tell me, at which point a call to transact() in
> > > Binder.java
> > > gets to native world? Is it android_util_Binder.cpp directly or are
> > > other classes used?
>
> > > Hit me with a cluestick, as I am running in circles!
>
> > > Thanks,
> > > Martin
>
> > --
> > Dianne Hackborn
> > Android framework engineer
> > [email protected]
>
> > Note: please don't send private questions to me, as I don't have time to
> > provide private support.  All such questions should be posted on public
> > forums, where I and others can see and answer them.
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups 
"android-framework" group.
To post to this group, send email to [email protected]
To unsubscribe from this group, send email to 
[email protected]
For more options, visit this group at 
http://groups.google.com/group/android-framework?hl=en
-~----------~----~----~----~------~----~------~--~---

Reply via email to