presto-main/src/main/java/io/prestosql/server/PluginManager.java/PluginManager/buildClassLoaderFromPom
class PluginManager:    private PluginClassLoader buildClassLoaderFromPom(File pomFile)
            throws Exception
    {
        List<Artifact> artifacts = resolver.resolvePom(pomFile);
        PluginClassLoader classLoader = createClassLoader(artifacts, pomFile.getPath());

        Artifact artifact = artifacts.get(0);
        Set<String> plugins = discoverPlugins(artifact, classLoader);
        if (!plugins.isEmpty()) {
            writePluginServices(plugins, artifact.getFile());
        }

        return classLoader;
    }