presto-main/src/main/java/io/prestosql/server/PluginManager.java/PluginManager/createClassLoader
class PluginManager:    private PluginClassLoader createClassLoader(List<Artifact> artifacts, String name)
            throws IOException
    {
        log.info("Classpath for %s:", name);
        List<URL> urls = new ArrayList<>();
        for (Artifact artifact : sortedArtifacts(artifacts)) {
            if (artifact.getFile() == null) {
                throw new RuntimeException("Could not resolve artifact: " + artifact);
            }
            File file = artifact.getFile().getCanonicalFile();
            log.info("    %s", file);
            urls.add(file.toURI().toURL());
        }
        return createClassLoader(urls);
    }