How to use

loadState

method

in

org.apache.tinkerpop.gremlin.process.computer.VertexProgram

/**
 * A helper method to construct a {@link VertexProgram} given the content of the supplied configuration.
 * The class of the VertexProgram is read from the {@link VertexProgram#VERTEX_PROGRAM} static configuration key.
 * Once the VertexProgram is constructed, {@link VertexProgram#loadState} method is called with the provided graph and configuration.
 *
 * @param graph         The graph that the vertex program will execute against
 * @param configuration A configuration with requisite information to build a vertex program
 * @param <V>           The vertex program type
 * @return the newly constructed vertex program
 */
public static <V extends VertexProgram> V createVertexProgram(final Graph graph, final Configuration configuration) {
  try {
    final Class<V> vertexProgramClass = (Class) Class.forName(configuration.getString(VERTEX_PROGRAM));
    final Constructor<V> constructor = vertexProgramClass.getDeclaredConstructor();
    constructor.setAccessible(true);
    final V vertexProgram = constructor.newInstance();
    vertexProgram.loadState(graph, configuration);
    return vertexProgram;
  } catch (final Exception e) {
    throw new IllegalStateException(e.getMessage(), e);
  }
}

@Override
public void loadState(final Graph graph, final Configuration configuration) {
  VertexProgram.super.loadState(graph, configuration);
  this.traversal = PureTraversal.loadState(configuration, VertexProgramStep.ROOT_TRAVERSAL, graph);
  this.haltedTraversers = TraversalVertexProgram.loadHaltedTraversers(configuration);
  this.programStep = new TraversalMatrix<>(this.traversal.get()).getStepById(configuration.getString(ProgramVertexProgramStep.STEP_ID));
  this.memoryComputeKeys.addAll(MemoryTraversalSideEffects.getMemoryComputeKeys(this.traversal.get()));
  this.memoryComputeKeys.add(MemoryComputeKey.of(TraversalVertexProgram.HALTED_TRAVERSERS, Operator.addAll, false, false));
  this.memoryComputeKeys.add(MemoryComputeKey.of(TraversalVertexProgram.ACTIVE_TRAVERSERS, Operator.addAll, true, true));
}

/**
 * A helper method to construct a {@link VertexProgram} given the content of the supplied configuration.
 * The class of the VertexProgram is read from the {@link VertexProgram#VERTEX_PROGRAM} static configuration key.
 * Once the VertexProgram is constructed, {@link VertexProgram#loadState} method is called with the provided graph and configuration.
 *
 * @param graph         The graph that the vertex program will execute against
 * @param configuration A configuration with requisite information to build a vertex program
 * @param <V>           The vertex program type
 * @return the newly constructed vertex program
 */
public static <V extends VertexProgram> V createVertexProgram(final Graph graph, final Configuration configuration) {
  try {
    final Class<V> vertexProgramClass = (Class) Class.forName(configuration.getString(VERTEX_PROGRAM));
    final Constructor<V> constructor = vertexProgramClass.getDeclaredConstructor();
    constructor.setAccessible(true);
    final V vertexProgram = constructor.newInstance();
    vertexProgram.loadState(graph, configuration);
    return vertexProgram;
  } catch (final Exception e) {
    throw new IllegalStateException(e.getMessage(), e);
  }
}

@Override
public void loadState(final Graph graph, final Configuration configuration) {
  VertexProgram.super.loadState(graph, configuration);
  this.traversal = PureTraversal.loadState(configuration, VertexProgramStep.ROOT_TRAVERSAL, graph);
  this.haltedTraversers = TraversalVertexProgram.loadHaltedTraversers(configuration);
  this.programStep = new TraversalMatrix<>(this.traversal.get()).getStepById(configuration.getString(ProgramVertexProgramStep.STEP_ID));
  this.memoryComputeKeys.addAll(MemoryTraversalSideEffects.getMemoryComputeKeys(this.traversal.get()));
  this.memoryComputeKeys.add(MemoryComputeKey.of(TraversalVertexProgram.HALTED_TRAVERSERS, Operator.addAll, false, false));
  this.memoryComputeKeys.add(MemoryComputeKey.of(TraversalVertexProgram.ACTIVE_TRAVERSERS, Operator.addAll, true, true));
}