class ServiceReferenceGraphNode

class ServiceReferenceGraphNode {
  private $id;
  private $inEdges;
  private $outEdges;
  private $value;

  /**
   * Constructor.
   *
   * @param string $id    The node identifier
   * @param mixed  $value The node value
   */
  public function __construct($id, $value) {
    $this->id = $id;
    $this->value = $value;
    $this->inEdges = array();
    $this->outEdges = array();
  }

  /**
   * Adds an in edge to this node.
   *
   * @param ServiceReferenceGraphEdge $edge
   */
  public function addInEdge(ServiceReferenceGraphEdge $edge) {
    $this->inEdges[] = $edge;
  }

  /**
   * Adds an out edge to this node.
   *
   * @param ServiceReferenceGraphEdge $edge
   */
  public function addOutEdge(ServiceReferenceGraphEdge $edge) {
    $this->outEdges[] = $edge;
  }

  /**
   * Checks if the value of this node is an Alias.
   *
   * @return Boolean True if the value is an Alias instance
   */
  public function isAlias() {
    return $this->value instanceof Alias;
  }

  /**
   * Checks if the value of this node is a Definition.
   *
   * @return Boolean True if the value is a Definition instance
   */
  public function isDefinition() {
    return $this->value instanceof Definition;
  }

  /**
   * Returns the identifier.
   *
   * @return string
   */
  public function getId() {
    return $this->id;
  }

  /**
   * Returns the in edges.
   *
   * @return array The in ServiceReferenceGraphEdge array
   */
  public function getInEdges() {
    return $this->inEdges;
  }

  /**
   * Returns the out edges.
   *
   * @return array The out ServiceReferenceGraphEdge array
   */
  public function getOutEdges() {
    return $this->outEdges;
  }

  /**
   * Returns the value of this Node
   *
   * @return mixed The value
   */
  public function getValue() {
    return $this->value;
  }

}