Iterator<N> successorIterator = ImmutableSet.<N>of().iterator();

  static <N> EndpointPairIterator<N> of(BaseGraph<N> graph) {
    return graph.isDirected() ? new Directed<N>(graph) : new Undirected<N>(graph);
  }

  private EndpointPairIterator(BaseGraph<N> graph) {
    this.graph = graph;
    this.nodeIterator = graph.nodes().iterator();
  }

  /**

 *
 * <h3>Usage</h3>
 *
 * Given an algorithm, for example:
 *
 * {@snippet :
 * public <N> someGraphAlgorithm(N startNode, SuccessorsFunction<N> successorsFunction);
 * }
 *
 * you will invoke it depending on the graph representation you're using.
 *
 * <p>If you have an instance of one of the primary {@code common.graph} types ({@link Graph},
 * {@link ValueGraph}, and {@link Network}):

         *       v3-v4
         *
         */
        v1 = graph.addVertex(new ArtifactMetadata("g", "a1", "1.0"));
        graph.setEntry(v1);
        v2 = graph.addVertex(new ArtifactMetadata("g", "a2", "1.0"));
        v3 = graph.addVertex(new ArtifactMetadata("g", "a3", "1.0"));
        v4 = graph.addVertex(new ArtifactMetadata("g", "a4", "1.0"));

        // v1-->v2
        graph.addEdge(v1, v2, new MetadataGraphEdge("1.1", true, null, null, 2, 1));

/**
 * Helper class to convert a metadata Graph into some form of a classpath
 *
 *
 */
@Deprecated
public interface ClasspathTransformation {
    String ROLE = ClasspathTransformation.class.getName();

    /**
     * Transform Graph into a Collection of metadata objects that
     * could serve as a classpath for a particular scope
     *
     * @param dirtyGraph - dependency graph
     * @param scope - which classpath to extract

 *
 * {@snippet :
 * // Building a mutable value graph
 * MutableValueGraph<String, Double> graph =
 *     ValueGraphBuilder.undirected().allowsSelfLoops(true).build();
 * graph.putEdgeValue("San Francisco", "San Francisco", 0.0);
 * graph.putEdgeValue("San Jose", "San Jose", 0.0);
 * graph.putEdgeValue("San Francisco", "San Jose", 48.4);
 *
 * // Building an immutable value graph
 * ImmutableValueGraph<String, Double> immutableGraph =

#include "tensorflow/core/framework/node_def.pb.h"
#include "tensorflow/core/framework/node_def_util.h"
#include "tensorflow/core/framework/tensor.pb.h"  // NOLINT
#include "tensorflow/core/framework/types.h"
#include "tensorflow/core/graph/graph.h"
#include "tensorflow/core/platform/base64.h"
#include "tensorflow/core/platform/strcat.h"
#include "tensorflow/core/util/debug_data_dumper.h"

using tensorflow::errors::InvalidArgument;

namespace tensorflow {

// API for driving Graph execution.

typedef struct TF_Session TF_Session;

// Return a new execution session with the associated graph, or NULL on
// error. Does not take ownership of any input parameters.
//
// *`graph` must be a valid graph (not deleted or nullptr). `graph` will be
// kept alive for the lifetime of the returned TF_Session. New nodes can still
// be added to `graph` after this call.

    }
  }

  // Run the host graph, which now contains a function and check that
  // outputs are as expected.
  void Run(const std::vector<std::pair<TF_Operation*, TF_Tensor*>>& inputs,
           std::initializer_list<TF_Output> outputs,
           const std::vector<int32_t>& expected_results) {
    // Create a session for this graph.
    CSession csession(host_graph_, s_);

   *
   * <p>If the graph is directed, the resultant edge will be directed; otherwise, it will be
   * undirected.
   *
   * <p>If this graph is directed, {@code endpoints} must be ordered.
   *
   * <p>Values do not have to be unique. However, values must be non-null.
   *
   * <p>If either or both endpoints are not already present in this graph, this method will silently

        return this;
    }

    /**
     * Gets the artifact filter that controls traversal of the dependency graph.
     *
     * @return The filter used to determine which of the artifacts in the dependency graph should be traversed or
     *         {@code null} to collect all transitive dependencies.
     */
    public ArtifactFilter getCollectionFilter() {