From: Tom Mueller <Tom.Mueller_at_oracle.com>
Date: Wed, 12 Dec 2012 09:24:11 -0600

GlassFish is a 100% Java application, so the code doesn't have a notion
of 32-bit vs. 64-bit.
How it runs is determined by the JVM it is running on. You can see the
version of
your JVM by running "java -version". For example, on my system it says:

$ java -version
java version "1.7.0_09"
Java(TM) SE Runtime Environment (build 1.7.0_09-b05)
Java HotSpot(TM) 64-Bit Server VM (build 23.5-b02, mixed mode)

So GlassFish will run in 64-bit mode if running on this JVM.

Tom