Re: Using JNI to determine whether an object implements an interface

"Mike Schilling" <>
Sun, 21 Nov 2010 14:38:32 -0800
"Steve Sobol" <> wrote in message

On Sun, 21 Nov 2010 21:52:24 +0000 (UTC)
Martin Gregorie <martin@address-in-sig.invalid> wrote:

On Sun, 21 Nov 2010 11:58:40 -0800, Steve Sobol wrote:

Yes. Really, my goals are (a) tight integration with the OS and (b)
convenience. I mean, sure, you could use JMX to control your app. But
how are you going to launch that app? I'm not all that familiar with
JMX/RMI/CORBA, but my impression is that you still need some mechanism
to instantiate and control Java objects.

In a *nix environment all you need do is "java progname args &" and its
off and running as a background task, or you can use the 'daemon' shell
script function.


Agreed, although as mentioned, part of the problem with "java progname
args &" is what shows up when you do a 'ps' -- I want to be able to see my
app's name, not "java" followed by a long list of arguments.

Anything else is done by sending signals to the service, not something
Java can easily handle

Martin, you are a genius. :) I'd completely forgotten about using
signals... probably because it's been a LONG time since the last time I
did any serious *ix programming.

Say I have a program written in Java - let's call it

I use LaunchJVM to create a native launcher, let's call it

If you send a signal to such a program, you'll be sending the signal to my
C++ stub (linux-native-service), which can trap the signal and take the
appropriate action (i.e., call one of the methods exposed by

Are you sure the JVM won't establish its own signal handling (or,
conversely, that having your native code establish signal handling after the
JVM starts up won't break the JVM)?

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