**NOTE:**

  /**
   * Returns the subgraph of {@code graph} induced by {@code nodes}. This subgraph is a new graph
   * that contains all of the nodes in {@code nodes}, and all of the {@link Graph#edges() edges}
   * from {@code graph} for which both nodes are contained by {@code nodes}.
   *
   * @throws IllegalArgumentException if any element in {@code nodes} is not a node in the graph
   */

  /**
   * Returns the subgraph of {@code graph} induced by {@code nodes}. This subgraph is a new graph
   * that contains all of the nodes in {@code nodes}, and all of the {@link Graph#edges() edges}
   * from {@code graph} for which both nodes are contained by {@code nodes}.
   *
   * @throws IllegalArgumentException if any element in {@code nodes} is not a node in the graph
   */

 * whose edges are <a
 * href="https://github.com/google/guava/wiki/GraphsExplained#uniqueness">unique</a> objects.
 *
 * <p>A graph is composed of a set of nodes and a set of edges connecting pairs of nodes.
 *
 * <p>There are three primary interfaces provided to represent graphs. In order of increasing
 * complexity they are: {@link Graph}, {@link ValueGraph}, and {@link Network}. You should generally

     *
     * @param tree "dirty" tree root
     * @param versionedVertices true if graph nodes should be versioned (different versions -> different nodes)
     * @param scopedVertices true if graph nodes should be versioned and scoped
     * (different versions and/or scopes -> different nodes)
     *
     */
    public MetadataGraph(MetadataTreeNode tree, boolean versionedVertices, boolean scopedVertices)

        writeElastisearchJsonApi(zos, id, "nodes", "stats");
        writeElastisearchJsonApi(zos, id, "nodes", "_all");
        writeElastisearchJsonApi(zos, id, "nodes", "usage");
        writeElastisearchJsonApi(zos, id, "remote", "info");
        writeElastisearchJsonApi(zos, id, "tasks", "");
        writeElastisearchJsonApi(zos, id, "nodes", "hot_threads");
    }

    /**

/**
 * An immutable pair representing the two endpoints of an edge in a graph. The {@link EndpointPair}
 * of a directed edge is an ordered pair of nodes ({@link #source()} and {@link #target()}). The
 * {@link EndpointPair} of an undirected edge is an unordered pair of nodes ({@link #nodeU()} and
 * {@link #nodeV()}).
 *
 * <p>The edge is a self-loop if, and only if, the two endpoints are equal.
 *
 * @author James Sexton

      LockGraphNode node = new LockGraphNode(getLockName(key));
      nodes.add(node);
      map.put(key, node);
    }
    // Pre-populate all allowedPriorLocks with nodes of smaller ordinal.
    for (int i = 1; i < numKeys; i++) {
      nodes.get(i).checkAcquiredLocks(Policies.THROW, nodes.subList(0, i));
    }
    // Pre-populate all disallowedPriorLocks with nodes of larger ordinal.
    for (int i = 0; i < numKeys - 1; i++) {

import okhttp3.Cache;
import okhttp3.HttpUrl;
import okhttp3.MediaType;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
import org.jsoup.Jsoup;
import org.jsoup.nodes.Document;
import org.jsoup.nodes.Element;

/**
 * Fetches HTML from a requested URL, follows the links, and repeats.
 */
public final class Crawler {
  private final OkHttpClient client;

     * @throws NullPointerException if name is null
     */
    @Nullable
    String attribute(@Nonnull String name);

    /**
     * Returns an immutable list of all child nodes.
     *
     * @return list of child nodes, never {@code null}
     */
    @Nonnull
    List<XmlNode> children();

    /**
     * Returns the first child node with the specified name.
     *