NoClassDefFoundError: Could not initialize class sun.awt.X11FontManager

Question

when we migrated from Oracle JDK-8 to Open JDK-11, Apache POI excel generation has issues

tried already -Djava.awt.headless=true

org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is java.lang.NoClassDefFoundError: Could not initialize class sun.awt.X11FontManager
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1053)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:998)
    at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:901)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:875)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)```

Answer 1

If you are using the docker 'slim images' of openjdk, the image no longer includes the packages 'fontconfig', and 'libfreetype6'.

Check the difference in docker file of openjdk:11-slim and the docker file of openjdk:8-slim.

You could either pick another docker image (e.g. openjdk:11-windowsservercore), or install the packages yourself in your docker file:

RUN apt-get update; apt-get install -y fontconfig libfreetype6 

Answer 2

The underlying issues is something else

I just created a simple class which does class loading of X11FontManager and when I ran it complained

unable to link "libfreetype6"

once I installed it using

apt-get install libfreetype6

started throwing could not link "libfontconfig1.so"

apt-get install libfontconfig1

that fixed the issue

Read this and understood few things https://medium.com/azulsystems/using-jlink-to-build-java-runtimes-for-non-modular-applications-9568c5e70ef4

Answer 3

Problem occurs when you use openjdk docker image in alpine version for example :

adoptopenjdk/openjdk11:jre-11.0.11_9-alpine.

You need chenge image to full version: adoptopenjdk/openjdk11:jre-11.0.11_9