NPE in FontManagerFactory when opening charts

[polychronov (Konstantin Polychronov)]

Hi all,
After upgrade to openHab 3.x on Synology I’ve got the below NPE when I open any chart on my sitemap. I use zulu11.45.27-ca-jdk11.0.10-linux_aarch32hf

I’ve read the following topic but does not seem to be able to apply simmilar solutions.

[SOLVED] Fonts error, not able to see any chart - 2.5.0~S1731-1 (Build #1731)

the solution is in: sudo apt-get install fontconfig:i386 did the trick for me (even on amd64 vm). Andrea

In this one people complain from the same using openJDK(zulu version) and it got resolved with getting back to Java 8 from oracle.

Problem accessing /chart

Hi Olaf I just checked some of my chart settings, and I do not define service="mysql" in the chart item. Maybe try it without it? This is my config for Temperature chart: Frame { Switch item=Temperature_Period icon="temperature2" label="Chart Period" mappings=[0="Day", 1="Week", 2="Two weeks"] Chart item=Temperature period=D refresh=30000 visibility=[Temperature_Period==0] Chart item=Temperature period=W refresh=300000 visibility=[Temperature_Period==1] Chart item=Temperature …

My main suspicion is that because there is no “official” Java 11 package for synology I’m missing some environment variable, related to the fonts. I’ve tried to reinstall Java 8 from oracle using the community provided synology package and see that it adds the following enviromnet variable CLASSPATH=.:$JAVA_HOME/lib
Tried it but does not seem to fix the issue.

Also saw this one on github (Charts not working on OpenJDK / Zulu JDK · Issue #421 · openhab/openhab-distro · GitHub) but not sure if I have to do something on synology. With Oracle Java8 on OH2.5 it worked without any additional packages…

The exception stacktrace:

Caused by: java.lang.reflect.InvocationTargetException
at jdk.internal.reflect.GeneratedConstructorAccessor884.newInstance(Unknown Source) ~[?:?]
at jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:?]
at java.lang.reflect.Constructor.newInstance(Constructor.java:490) ~[?:?]
at sun.font.FontManagerFactory$1.run(FontManagerFactory.java:84) ~[?:?]
… 53 more
Caused by: java.lang.NullPointerException
at sun.awt.FontConfiguration.getInitELC(FontConfiguration.java:465) ~[?:?]
at sun.awt.FontConfiguration.initFontConfig(FontConfiguration.java:441) ~[?:?]
at sun.awt.FontConfiguration.init(FontConfiguration.java:108) ~[?:?]
at sun.awt.X11FontManager.createFontConfiguration(X11FontManager.java:719) ~[?:?]
at sun.font.SunFontManager$2.run(SunFontManager.java:379) ~[?:?]
at java.security.AccessController.doPrivileged(Native Method) ~[?:?]
at sun.font.SunFontManager.(SunFontManager.java:324) ~[?:?]
at sun.awt.FcFontManager.(FcFontManager.java:35) ~[?:?]
at sun.awt.X11FontManager.(X11FontManager.java:56) ~[?:?]
at jdk.internal.reflect.GeneratedConstructorAccessor884.newInstance(Unknown Source) ~[?:?]
at jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) ~[?:?]
at java.lang.reflect.Constructor.newInstance(Constructor.java:490) ~[?:?]
at sun.font.FontManagerFactory$1.run(FontManagerFactory.java:84) ~[?:?]

Any help will be highly appreciated if anyone else got simmilar issues.

Cheers,
Konstantin