How do Mac and Linux find the JFX runtime?

Question

I've been searching the documentation without success for the answer to what ought to be a simple question -- how do I point Mac or Linux at the 2.2 runtime? It's no problem if I'm running in an IDE (NetBeans, e(fx)clipse), where I can tell the IDE where I unpacked the SDK. But what if I want to run a jar file, such as produced by the ant tasks?
You'd think this would work (on Linux, where I unpacked the SDK into /opt):
java -cp /opt/javafx-sdk2.2.0-beta/rt/lib/jfxrt.jar:. -jar MyProgram.jar But it doesn't -- I get a popup saying "This application requires a newer version of the Java runtime. Please download and install the latest Java runtime from java.com. Then restart the application" (I'm running with 1.7.0_05-b05 from Oracle).
The only thing at all close I find in the Linux installation instructions is it says to unpack the samples as a subdirectory of the SDK, wherever I happened to put it, and then I should be able to run the examples with a simple "java -jar filename.jar". But even that's not quite true -- it only works if I first cd to the samples directory. But it's a start, so I tried...
cd /opt/javafx-sdk2.2.0-beta/rt
java -jar ~/dist/MyProgram.jarThat succeeds in finding the runtime, but my program doesn't work, because it doesn't find my dependent libraries. So I tweaked the command a little bit:
cd /opt/javafx-sdk2.2.0-beta/rt
java -cp ~/dist/MyProgram.jar -jar ~/dist/MyProgram.jarThat actually works. But it can't possibly be the right answer -- you shouldn't have to run a javafx program with the runtime directory as your working directory.
And even that doesn't work on Mac. There, Java knows how to find the runtime that's installed with JDK 7 update 5 for Mac. But if I want to test a program with the 2.2 runtime, what do I do? Setting -classpath on the command line still uses the 2.1 runtime. And if I try the trick of connecting to javafx-sdk2.2.0-beta/rt first, it doesn't work at all -- it doesn't find my libraries, and it throws up a "java quit unexpectedly" window after getting a segfault.
So what's a developer to do? Am I supposed to use the native packaging procedure instead?

Answer 1

JavaFX 2.2 is first version where Linux/Mac are supported as runtime (and not just SDK).
However, you need to install JavaFX Runtime that is part of JRE 7u6 (you can get beta from jdk7.java.net or wait for FCS version of it).
Installing JRE is the only way to get JavaFX runtime installed on Mac and Linux (and eventually on Windows too).
rt folder in the SDK is "private" copy of the runtime. It is not supposed to be used to run arbitrary JavaFX applications by default.
You can still force to use it as
java -Djavafx.runtime.path=/opt/javafx-sdk2.2.0-beta/rt/lib/jfxrt.jar -jar MyProgram.jar
or
java -cp ~/dist/MyProgram.jar:/opt/javafx-sdk2.2.0-beta/rt/lib/jfxrt.jar com.javafx.main.Main
Note that if you use "-jar" then "-cp" is ignored by java launcher. This is not JavaFX specific behavior.
JavaFX specific part is that properly packaged JavaFX main jar file will include copy of launcher class (com.javafx.main.Main)
and this is what will be run when you double click on jar or use "java -jar". Launcher will try to locate JavaFX runtime to use,
it knows how to find runtime in the SDK if it is sample located in the SDK itself and it also knows how to find installed version of runtime.
If JavaFX is not found then it will show you message you observed.