public PluginClassLoader newPluginClassLoader(URL pluginLocation, URL[] urls, ClassLoader parent) {
        return AccessController.doPrivileged(
                (PrivilegedAction<PluginClassLoader>) () -> new PluginClassLoader(pluginLocation, urls, parent)
        );
    }
Factory for {@link DelegatingClassLoader} and {@link PluginClassLoader} instances.
Used for mocking classloader initialization in tests.
connect/runtime/src/main/java/org/apache/kafka/connect/runtime/isolation/ClassLoaderFactory.java