64bit jdk applications can be run on 32bit jres?

Newbie & Debugging Questions
#1

hello,

if i use sun’s 64bit jdk, will the applications i build with it only be runnable on 64bit jres or will they run on the more widely spread 32bit jres as well?

speaking of 64bit. if i am not mistaken, there is no javaws.exe shipping with suns 64bit jre. does anyone know of a way to still get webstart (jnlp) running on 64bit?

thanks!

#2

[quote]will they run on the more widely spread 32bit jres as well?
[/quote]
Of course! It’s only the VM that’s 64bit, the byte code is platform independent. WORA, remember? :slight_smile:

#3

thanks! but then why do some java software explicitly require a 64bit jvm to run?

example: eclipse
http://download.eclipse.org/eclipse/downloads/drops/S-3.4M6a-200804091425/download.php?dropFile=eclipse-SDK-3.4M6a-win32-x86_64.zip

#4

It relies on native libraries (like SWT)

#5

ok, thanks!

but what do natives have to do with the JVM then? i thought they are executed by the OS (which of course has to be 64bit) itself and not by the VM.

#6

The native .dll is called by the JVM through JNI. I could imagine that calling a 64bit native from a 32bit JVM won’t work.