* starting at the root object contained in this value source, apply each part
         * to the object graph below this root, using either 'getXXX()' or 'isXXX()'
         * accessor types to resolve the value for each successive expression part.
         * Finally, return the result of the last expression part's resolution.</p>
         *

              <exclude>org.apache.maven.toolchain.DefaultToolchainManager#logger</exclude>
              <!-- Remove plexus utils -->
              <exclude>org.apache.maven.project.ProjectSorter#getDAG():METHOD_REMOVED</exclude>
              <!-- classes moved to maven-compat -->
              <exclude>org.apache.maven.plugin.PluginManager</exclude>

 * their lifecycle is shared as well: once supplied repository system is shut-down, this instance becomes closed as
 * well. Any subsequent {@code getXXX} method invocation attempt will fail with {@link IllegalStateException}.
 */
public class RepositorySystemSupplier implements Supplier<RepositorySystem> {
    private final AtomicBoolean closed = new AtomicBoolean(false);