Broken on Windows 10

[WildGenius]

Error on OmegaT startup "An error occurred while processing an application startup event: java.lang.NoClassDefFoundError: javafx/application/Platform". Tried with Oracle's Java 8 and OpenJDK 15.0.2 with OpenJFX 15.0.1.

[WildGenius]

Since the latest omegaT comes with its own jre folder, it probably doesn't matter at all what java I install, does it? Is it then ok to just dump OpenJFX into the Omega's Java folder?

[yoursdearboy]

OpenJDK 15 must be ok.

Anyway, try the new version 1.4.0-rc.0. Thanks to @miurahr OpenJFX shouldn't be a problem now.

[WildGenius]

Now it's too new?.. "An error occurred while processing an application startup event: java.lang.UnsupportedClassVersionError: javafx/application/Platform has been compiled by a more recent version of the Java Runtime (class file version 54.0), this version of the Java Runtime only recognizes class file versions up to 52.0" Also, should have mentioned it in the OP, but the OmegaT version being used is "latest" 5.4.1.

[yoursdearboy]

Ok, looks like I see the problem.

1. Now we are using javafxplugin for Gradle to bundle Java FX with the plugin
2. But it includes binaries only for JDK 11 (which we use for builds) according to docs:

JavaFX modules require native binaries for each platform. The plugin only includes binaries for the platform running the build.

3. And OmegaT bundles JRE 1.8 which is not compatible with these binaries.

So, I think the best idea is to build the plugin for Java 1.8 with JavaFX. But the javafxplugin doesn't support Java 1.8, so it must be done manually 😱 What do you think @miurahr?

Also, to make the whole story clear:

• Oracle's Java <= 1.8 comes with JavaFX
• OpenJDK bundled JavaFX in the past, but today most distributions are without it

[miurahr]

OmegaT does not support Java 15. Please use Java 11 and OmegaT distribution without JRE.

[miurahr]

OmegaT with JRE bundles OpenJDK JRE 1.8 from AdoptOpenJDK distribution.
It does not support JavaFX, but support Java Web Start which OmegaT support.

https://adoptopenjdk.net/migration.html#migration-oracle

OpenJDK 11 from AdoptJDK supports JavaFX by separate distribution of OpenJFX but does not support Java Web Start.
It is why OmegaT stick to OpenJDK 8 for bundled JRE.

You can use following combinations on Windows platform.

• OmegaT Windows WITHOUT JRE

and

• Zulu OpenJDK with JFX(JRE-FX)

or

• AdoptOpenJDK 11