Engine doesn't build on openjdk-11

[grizeldi]

I was trying to do a gradle build of the engine using openjdk-11 and the build crashed with this as an error:

engine/jme3-core/src/plugins/java/com/jme3/font/plugins/BitmapFontLoader.java:46: error: package org.omg.PortableInterceptor does not exist
import org.omg.PortableInterceptor.SYSTEM_EXCEPTION;
                                  ^
Note: Some input files use or override a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
Note: Some input files use unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
1 error

> Task :jme3-core:compileJava FAILED

Googling around a bit, it seems like that package doesn't exist in Java versions greater than 8. Reverting to openjdk-8 builds fine.

[MeFisto94]

Easy Fix, this import isn't used at all in the said code anyway.