Trouble creating an update button

[Colin McTaggart]

Hi all,
I have just tried to create an automatic update button for an application of mine. First my app checks if a newer version is available, if so it then it is supposed to start an updating app which downloads the latest version of the program (which is an executable Jar). The updater then replaces the old version with the new one and starts the new version running. In order to replace the old file with the new one I need to shut down the old version.

I have tried using System.exit(0); but this seems to shut down my updater as well

Could someone please let me know where I am going wrong here? How can I shut down the original app without shutting down the updater?

[Paul Clapham]

You should run your updater as a separate process.

[Colin McTaggart]

How do I do that? I am a bit inexperienced as a programmer atm. Right now I run my updater using this code:

Process ps = Runtime.getRuntime().exec(new String[]{"java", "-jar", "Update.jar"});

[Paul Clapham]

Yup, that's how you should do it. But you say that shutting down the application which does that also causes that Process to be terminated?

[Colin McTaggart]

I just realized that I may not be passing in arguments properly to the updater... My code actually looks like this:

Process ps = Runtime.getRuntime().exec(new String[]{"java", "-jar", "Update.jar arg1 arg2 arg3"});

I'm going to test to see if this is the case.

[Colin McTaggart]

I tried replacing my update app with another that does not use arguments and it was shut down as well. Does System.exit(0); shut down every process running in the JVM? If so is there any was to shutdown a specific app in the JVM?

[Colin McTaggart]

I realized that my arguments had to be separated with commas and in their own sets of quotation marks so it works fine now. Thanks for the help

[Paul Clapham]

Glad it's fixed.

(So the answer was, it wasn't anything to do with the main application shutting down, it was just that the process you started always failed until you got that fixed?)

(And as you may have figured out by now, the phrase "process running in the JVM" doesn't mean anything. The process you create is an independent process which isn't "in the JVM" in any way. Just trying to clarify for the benefit of future readers.)

[Colin McTaggart]

Looks like I misunderstood how JVM works, I'll read up on that tomorrow. Thanks for pointing that out