public void addNode(final NodeType node) {
    Preconditions.checkNotNull(node, "Node argument can not be null");

    m_nodes.add(node);
    m_nodeToEdges.put(node, new ArrayList<EdgeType>());
  }
Adds a node to the graph.

@param node The node to add to the graph.
java/zylib/src/main/java/com/google/security/zynamics/zylib/types/graphs/MutableDirectedGraph.java