ContextFinder.class contains String literals and constants referring to "internal" classes, like:

private static final String PLATFORM_DEFAULT_FACTORY_CLASS = "com.sun.xml.internal.bind.v2.ContextFactory";

Class spFactory = ServiceLoaderUtil.safeLoadClass(className, "com.sun.xml.internal.bind.v2.ContextFactory", classLoader);

spi = ServiceLoaderUtil.safeLoadClass(className, "com.sun.xml.internal.bind.v2.ContextFactory", getContextClassLoader());

According to my understanding it's JAXB RI built into JDK which has "internal" packages. Standalone JAXB RI doesn't have such packages.

I believe standalone JAXB RI should refer to classes from standalone JAXB RI rather than from build-in JAXB RI.