How to use

singleton

method

in

org.grouplens.grapht.graph.DAGNode

/**
 * Get a singleton root node for a dependency graph.
 * @return A root node for a dependency graph with no resolved objects.
 */
public static DAGNode<Component,Dependency> rootNode() {
  return DAGNode.singleton(ROOT_SATISFACTION);
}

/**
 * Create a DependencySolver that uses the given functions, and max
 * depth of the dependency graph.
 * 
 * @param bindFunctions The binding functions that control desire bindings
 * @param maxDepth A maximum depth of the graph before it's determined that
 *            a cycle exists
 * @throws IllegalArgumentException if maxDepth is less than 1
 * @throws NullPointerException if bindFunctions is null
 */
DependencySolver(List<BindingFunction> bindFunctions,
         List<BindingFunction> triggers,
         CachePolicy defaultPolicy, int maxDepth) {
  Preconditions.notNull("bindFunctions", bindFunctions);
  Preconditions.notNull("defaultPolicy", defaultPolicy);
  if (maxDepth <= 0) {
    throw new IllegalArgumentException("Max depth must be at least 1");
  }
  
  this.functions = new ArrayList<BindingFunction>(bindFunctions);
  this.triggerFunctions = new ArrayList<BindingFunction>(triggers);
  this.maxDepth = maxDepth;
  this.defaultPolicy = defaultPolicy;
  
  graph = DAGNode.singleton(ROOT_SATISFACTION);
  backEdges = HashMultimap.create();
  mergePool = MergePool.create();
  logger.info("DependencySolver created, max depth: {}", maxDepth);
}

  node = DAGNode.singleton(result.makeSatisfaction());
  deferQueue.add(new Deferral(node, newContext));
} else {