So far the solution given here worked perfectly until I upgraded to 18.04, where I had to install other elements to make the icon appear. In the beginning it worked quite well, but now I am getting this:
Exception in thread "main" java.awt.AWTError: Assistive Technology not found: org.GNOME.Accessibility.AtkWrapper
at java.desktop/java.awt.Toolkit.newAWTError(Toolkit.java:472)
at java.desktop/java.awt.Toolkit.fallbackToLoadClassForAT(Toolkit.java:488)
at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:183)
at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177)
at java.base/java.util.HashMap$KeySpliterator.forEachRemaining(HashMap.java:1608)
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:150)
at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:173)
at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:497)
at java.desktop/java.awt.Toolkit.loadAssistiveTechnologies(Toolkit.java:532)
at java.desktop/java.awt.Toolkit.getDefaultToolkit(Toolkit.java:613)
at java.desktop/java.awt.SystemTray.isSupported(SystemTray.java:221)
at tav.TAV.main(TAV.java:93)
Caused by: java.lang.ClassNotFoundException: org.GNOME.Accessibility.AtkWrapper
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:582)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:190)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:499)
at java.base/java.lang.Class.forName0(Native Method)
at java.base/java.lang.Class.forName(Class.java:374)
at java.desktop/java.awt.Toolkit.fallbackToLoadClassForAT(Toolkit.java:485)
... 13 more
As the app is still working on a Windows machine, I do think the app has changed, so my question is, what is wrong here and why, and why did it work before? Thank you very much in advance.