Java 9 ClassCastException with URLClassLoader

[IanDCarroll]

cob_spec is having trouble with Java 9's module system. ClassLoaders can no longer be cast as URLClassLoaders.

Given: Using Java 9 and having added two lines to the pom.xml properties to allow mvn package to compile:

    <properties>
       ...
        <maven.compiler.source>9.0</maven.compiler.source>
        <maven.compiler.target>9.0</maven.compiler.target>
    </properties>

When: $ java -jar fitnesse.jar -p 9090

Then:

Exception in thread "main" java.lang.ClassCastException: java.base/jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to java.base/java.net.URLClassLoader
	at util.FileUtil.addUrlToClasspath(FileUtil.java:216)
	at util.FileUtil.addFileToClassPath(FileUtil.java:212)
	at util.FileUtil.addItemsToClasspath(FileUtil.java:207)
	at fitnesse.components.PluginsClassLoader.addPluginsToClassLoader(PluginsClassLoader.java:15)
	at fitnesseMain.FitNesseMain.loadPlugins(FitNesseMain.java:47)
	at fitnesseMain.FitNesseMain.launchFitNesse(FitNesseMain.java:35)
	at fitnesseMain.FitNesseMain.main(FitNesseMain.java:27)

Something I found online about the issue:

Also there's this link