예제 #1
0
  private boolean isInDistanceInternal(
      int distance, NetworkNode from, NetworkNode to, TwoNetworkNodes cachePairKey) {
    if (from.equals(to)) return true;

    if (distance == 0) return false;

    if (SimpleNetwork.areNodesConnecting(from, to)) return true;

    // Breadth-first search of the network
    Set<NetworkNode> visitedNodes = Sets.newHashSet();
    visitedNodes.add(from);

    Set<NetworkNode> networkingNodesToTest = Sets.newHashSet();
    listConnectedNotVisitedNetworkingNodes(visitedNodes, from, networkingNodesToTest);
    int distanceSearched = 1;
    while (distanceSearched < distance) {
      distanceSearched++;

      for (NetworkNode nodeToTest : networkingNodesToTest) {
        if (SimpleNetwork.areNodesConnecting(nodeToTest, to)) {
          distanceCache.put(cachePairKey, distanceSearched);
          return true;
        }
        visitedNodes.add(nodeToTest);
      }

      Set<NetworkNode> nextNetworkingNodesToTest = Sets.newHashSet();
      for (NetworkNode nodeToTest : networkingNodesToTest)
        listConnectedNotVisitedNetworkingNodes(visitedNodes, nodeToTest, nextNetworkingNodesToTest);

      networkingNodesToTest = nextNetworkingNodesToTest;
    }

    return false;
  }
예제 #2
0
  @Override
  public int getDistance(NetworkNode from, NetworkNode to) {
    TwoNetworkNodes nodePair = new TwoNetworkNodes(from, to);
    final Integer cachedDistance = distanceCache.get(nodePair);
    if (cachedDistance != null) return cachedDistance;

    if ((!hasNetworkingNode(from) && !hasLeafNode(from))
        || (!hasNetworkingNode(to) && !hasLeafNode(to)))
      throw new IllegalArgumentException("Cannot test nodes not in network");

    if (from.equals(to)) return 0;

    if (SimpleNetwork.areNodesConnecting(from, to)) return 1;

    // Breadth-first search of the network
    Set<NetworkNode> visitedNodes = Sets.newHashSet();
    visitedNodes.add(from);

    Set<NetworkNode> networkingNodesToTest = Sets.newHashSet();
    listConnectedNotVisitedNetworkingNodes(visitedNodes, from, networkingNodesToTest);
    int distanceSearched = 1;
    while (networkingNodesToTest.size() > 0) {
      distanceSearched++;

      for (NetworkNode nodeToTest : networkingNodesToTest) {
        if (SimpleNetwork.areNodesConnecting(nodeToTest, to)) {
          distanceCache.put(new TwoNetworkNodes(from, to), distanceSearched);
          return distanceSearched;
        }
        visitedNodes.add(nodeToTest);
      }

      Set<NetworkNode> nextNetworkingNodesToTest = Sets.newHashSet();
      for (NetworkNode nodeToTest : networkingNodesToTest)
        listConnectedNotVisitedNetworkingNodes(visitedNodes, nodeToTest, nextNetworkingNodesToTest);

      networkingNodesToTest = nextNetworkingNodesToTest;
    }
    return -1;
  }