@Test
  public void immutableValueGraphBuilder_addNode() {
    ImmutableValueGraph<String, Integer> graph =
        ValueGraphBuilder.directed().<String, Integer>immutable().addNode("A").build();

    assertThat(graph.nodes()).containsExactly("A");
    assertThat(graph.edges()).isEmpty();
  }

  @Test
  public void immutableValueGraphBuilder_putEdgeFromNodes() {
    ImmutableValueGraph<String, Integer> graph =

/**
 * The XPathAPI class provides methods to evaluate XPath expressions and select nodes or node lists from an XML document.
 * It uses the javax.xml.xpath.XPath and javax.xml.xpath.XPathFactory classes to create and evaluate XPath expressions.
 *
 * <p>Example usage:</p>
 * <pre>
 * {@code
 * XPathAPI xPathAPI = new XPathAPI();
 * NodeList nodes = xPathAPI.selectNodeList(contextNode, "//example");

		prometheus.NewDesc(
			prometheus.BuildFQName(minioNamespace, "nodes", "online"),
			"Total number of MinIO nodes online",
			nil, nil),
		prometheus.GaugeValue,
		float64(nodesUp),
	)
	ch <- prometheus.MustNewConstMetric(
		prometheus.NewDesc(
			prometheus.BuildFQName(minioNamespace, "nodes", "offline"),
			"Total number of MinIO nodes offline",
			nil, nil),
		prometheus.GaugeValue,
		float64(nodesDown),

     * @return the root node of the dependency graph or {@code null} if none
     */
    @Nullable
    Node getRoot();

    /**
     * The ordered list of the flattened dependency nodes.
     *
     * @return the ordered list of the flattened dependency nodes
     */
    @Nonnull
    List<Node> getNodes();

    /**
     * Returns the file paths of all dependencies, regardless of which tool option those paths should be placed on.

```yaml
version: v2
address: ":9000"
rootUser: "minioadmin"
rootPassword: "minioadmin"
console-address: ":9001"
certs-dir: "/home/user/.minio/certs/"
pools: # Specify the nodes and drives with pools
  - args:
      - "https://server-example-pool1:9000/mnt/disk{1...4}/"
      - "https://server{1...2}-pool1:9000/mnt/disk{1...4}/"
      - "https://server3-pool1:9000/mnt/disk{1...4}/"

    // whatever ordering the graph's nodes do, so ImmutableSortedMap is unnecessary even if the
    // input nodes are sorted.
    ImmutableMap.Builder<N, GraphConnections<N, V>> nodeConnections = ImmutableMap.builder();
    for (N node : graph.nodes()) {
      nodeConnections.put(node, connectionsOf(graph, node));
    }
    return nodeConnections.buildOrThrow();
  }

version: v1
address: ':9000'
console-address: ':9001'
certs-dir: '/home/user/.minio/certs/'
pools: # Specify the nodes and drives with pools
  -
        - 'https://server-example-pool1:9000/mnt/disk{1...4}/'
        - 'https://server{1...2}-pool1:9000/mnt/disk{1...4}/'
        - 'https://server3-pool1:9000/mnt/disk{1...4}/'
        - 'https://server4-pool1:9000/mnt/disk{1...4}/'
  -
        - 'https://server-example-pool2:9000/mnt/disk{1...4}/'

 * @since 23.0
 */
@Beta
@DoNotMock("Implement with a lambda, or use GraphBuilder to build a Graph with the desired edges")
public interface PredecessorsFunction<N> {

  /**
   * Returns all nodes in this graph adjacent to {@code node} which can be reached by traversing
   * {@code node}'s incoming edges <i>against</i> the direction (if any) of the edge.
   *

    RoundToDoubleTester(BigDecimal input) {
      this.input = input;
    }

    @CanIgnoreReturnValue
    RoundToDoubleTester setExpectation(double expectedValue, RoundingMode... modes) {
      for (RoundingMode mode : modes) {
        Double previous = expectedValues.put(mode, expectedValue);
        if (previous != null) {
          throw new AssertionError();
        }
      }
      return this;
    }

    }

    /**
     * Gets the XPath expression for selecting target nodes.
     *
     * @return the target node path
     */
    public String getTargetNodePath() {
        return targetNodePath;
    }

    /**
     * Sets the XPath expression for selecting target nodes.
     *
     * @param targetNodePath the target node path to set
     */