Exception in thread "main" java.lang.ClassCastException: class jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to class java.net.URLClassLoader

[avalitan]

Exception in thread "main" java.lang.ClassCastException: class jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to class java.net.URLClassLoader (jdk.internal.loader.ClassLoaders$AppClassLoader and java.net.URLClassLoader are in module java.base of loader 'bootstrap') at com.net2plan.internal.SystemUtils.getClasspath(SystemUtils.java:173) at com.net2plan.internal.SystemUtils.configureEnvironment(SystemUtils.java:153) at com.net2plan.gui.GUINet2Plan.main(GUINet2Plan.java:518)

java --version openjdk 11.0.6 2020-01-14 OpenJDK Runtime Environment (build 11.0.6+10) OpenJDK 64-Bit Server VM (build 11.0.6+10, mixed mode)

[zombie12344321]

Did you ever figure this issue out?

[robinchrist]

I had the same issue. Try with Java 8, anything newer doesn't seem to work.

sudo apt install openjdk-8-jre
/usr/lib/jvm/java-8-openjdk-amd64/bin/java -jar Net2Plan.jar

For Ubuntu.