/**
   * Connect vertices in the graph. Connects vertices if startVertex and endVertex may be connected
   * by a directed edge. Ensures that: * startVertex is a RequiredPort and endVertex is a
   * ProvidedPort * the required port has not yet reached the maximal number of connections {@link
   * RequiredPort.getMaxDegree() getMaxDegree} * the ports do not belong to the same component * the
   * ports are not yet connected
   *
   * @param startVertex
   * @param endVertex
   * @param graph
   * @return true if the two vertexes were connected
   */
  protected boolean connect(NubiSaveVertex startVertex, NubiSaveVertex endVertex) {
    boolean shouldNotConnect = shouldNotConnect(startVertex, endVertex);
    System.out.println("nubisavecomponentgraphmouseplugin: connect");
    if (shouldNotConnect) {
      System.out.println("nubisavecomponentgraphmouseplugin: returning false");
      return false;
    }
    AbstractNubisaveComponent start =
        (AbstractNubisaveComponent) ((RequiredPort) startVertex).getParentComponent();
    AbstractNubisaveComponent end =
        (AbstractNubisaveComponent) ((ProvidedPort) endVertex).getParentComponent();
    if (!isConnected(startVertex, endVertex)) {
      BufferedWriter writer = null;
      try {
        System.out.println("is not connected");
        start.connectToProvidedPort(end);
        WeightedNubisaveVertexEdge edge = edgeFactory.create();
        edge.setWeight(end.getNrOfFilePartsToStore());
        graph.addEdge(edge, startVertex, endVertex, EdgeType.DIRECTED);
        File file = new File(storage_directory + "/" + "connections.txt");
        if (!file.exists()) {
          file.createNewFile();
        }
        writer = new BufferedWriter(new FileWriter(file, true));
        writer.write(start.getUniqueName());
        writer.write(" ");
        writer.write(end.getUniqueName());
        writer.newLine();
        writer.close();
      } catch (IOException ex) {
        Logger.getLogger(AbstractNubisaveComponentEdgeCreator.class.getName())
            .log(Level.SEVERE, null, ex);
      } finally {
        try {
          writer.close();
        } catch (IOException ex) {
          Logger.getLogger(AbstractNubisaveComponentEdgeCreator.class.getName())
              .log(Level.SEVERE, null, ex);
        }
      }

    } else {
      System.out.println("is  connected --> increase weight");
      WeightedNubisaveVertexEdge edge =
          (WeightedNubisaveVertexEdge) graph.findEdge(startVertex, endVertex);
      System.out.println("edge weight: " + edge.getWeight());
      int before = end.getNrOfFilePartsToStore();
      System.out.println("nroffileparts1: " + before);
      end.setNrOfFilePartsToStore(end.getNrOfFilePartsToStore() + 1);
      System.out.println("nroffileparts2: " + end.getNrOfFilePartsToStore());
      assert (end.getNrOfFilePartsToStore() - 1) == before;
      edge.setWeight(end.getNrOfFilePartsToStore());
      assert (edge.getWeight() - 1) == before;
      System.out.println("incrreased edge weight: " + edge.getWeight());
    }
    System.out.println("nubisavecomponentgraphmouseplugin: returning true");
    return true;
  }
Пример #2
0
  /**
   * Searches the graph and searches for the shortest path from a given start node to the
   * destination. Returns {@code null} if there are no vertices, edges, or path to the goal,
   * otherwise a list with the order of vertices on the shortest path.
   *
   * @param graph The graph to search
   * @param source The vertex to start the search from
   * @param destination The goal vertex
   * @return A list with the order of vertices on the shortest path, null if no path exists in the
   *     graph.
   */
  public List<V> search(Graph<V, E> graph, V source, V destination) {

    // Check if it is even possible to find a path, return null
    // if the graph has no vertices or edges
    if (graph.getVertexCount() == 0) {
      System.out.println("No nodes in the graph, " + "no shortest path can be found");
      return null;
    } else if (graph.getEdgeCount() == 0) {
      System.out.println("No edges in graph, no path " + "can be found");
      return null;
    }

    // Keep record of distance to each vertex, map each vertex
    // in the graph to it's distance
    HashMap<V, Number> distanceTable = new HashMap<>();

    // Unvisited node queue, uses a pair <Vertex, Double> and ordered
    // by the distance to the vertex
    PriorityQueue<Pair<V, Number>> queue = new PriorityQueue<>(new QueueComparator());

    // Map of nodes on the path, parents is value, key is child
    HashMap<V, V> parent = new HashMap<>();

    Number maxValue;
    E edgeTest = graph.getEdges().iterator().next();

    // This is so ugly, I hate Java Numbers
    int numberType = 0;
    if (edgeTest.getWeight() instanceof Integer) {
      numberType = 1;
    } else if (edgeTest.getWeight() instanceof Double) {
      numberType = 2;
    }
    // Place each vertex in the map, initialize distances and put
    // the pairings into the queue.
    for (V vertex : graph.getVertices()) {
      if (numberType == 1) {
        maxValue = Integer.MAX_VALUE;
        if (vertex.equals(source)) {
          distanceTable.put(source, 0);
          queue.add(new Pair<>(vertex, 0));
        } else {
          distanceTable.put(vertex, Integer.MAX_VALUE);
          queue.add(new Pair<>(vertex, maxValue));
        }
      } else if (numberType == 2) {
        maxValue = Double.MAX_VALUE;
        if (vertex.equals(source)) {
          distanceTable.put(source, 0.0);
          queue.add(new Pair<>(vertex, 0.0));
        } else {
          distanceTable.put(vertex, Double.MAX_VALUE);
          queue.add(new Pair<>(vertex, maxValue));
        }
      }
    }

    parent.put(source, null);

    while (!queue.isEmpty()) {

      Pair<V, Number> topPair = queue.remove();
      V vertex = topPair.getLeft();

      // Goal test, return the list of nodes on the path
      // if we reach the destination
      if (vertex.equals(destination)) {
        return tracePath(parent, destination);
      }

      Collection<V> neighbours = graph.getNeighbors(vertex);

      for (V neighbour : neighbours) {

        E edge = graph.findEdge(vertex, neighbour);
        assert (edge != null);

        // Test for type of number used for weight, work accordingly
        // Did I mention I hate the Java Number class.
        if (numberType == 1) {

          Integer alternateDistance = (Integer) edge.getWeight();

          if (alternateDistance < (Integer) distanceTable.get(neighbour)) {
            distanceTable.put(neighbour, alternateDistance);
            parent.put(neighbour, vertex);
            queue.add(new Pair<>(neighbour, alternateDistance));
          }
        } else if (numberType == 2) {
          Double alternateDistance = (Double) edge.getWeight();

          if (alternateDistance < (Double) distanceTable.get(neighbour)) {
            distanceTable.put(neighbour, alternateDistance);
            parent.put(neighbour, vertex);
            queue.add(new Pair<>(neighbour, alternateDistance));
          }
        }
      }
    }
    // Exhausted all possible paths from source, could not find a path
    // to the goal.
    return null;
  }
Пример #3
0
  public void testMixedSaveLoadSave() throws IOException {
    Graph<Number, Number> graph1 = new SparseMultigraph<Number, Number>();
    for (int i = 0; i < 5; i++) {
      graph1.addVertex(i);
    }
    int j = 0;

    List<Number> id = new ArrayList<Number>(graph1.getVertices());
    GreekLabels<Number> gl = new GreekLabels<Number>(id);
    Number[] edges = {0, 1, 2, 3, 4, 5};

    graph1.addEdge(j++, 0, 1, EdgeType.DIRECTED);
    graph1.addEdge(j++, 0, 2, EdgeType.DIRECTED);
    graph1.addEdge(j++, 1, 2, EdgeType.DIRECTED);
    graph1.addEdge(j++, 1, 3);
    graph1.addEdge(j++, 1, 4);
    graph1.addEdge(j++, 4, 3);

    Map<Number, Number> nr = new HashMap<Number, Number>();
    for (int i = 0; i < edges.length; i++) {
      nr.put(edges[i], new Float(Math.random()));
    }

    assertEquals(graph1.getEdgeCount(), 6);

    //        System.err.println(" mixed graph1 = "+graph1);
    //        for(Number edge : graph1.getEdges()) {
    //        	System.err.println("edge "+edge+" is directed? "+graph1.getEdgeType(edge));
    //        }
    //        for(Number v : graph1.getVertices()) {
    //        	System.err.println(v+" outedges are "+graph1.getOutEdges(v));
    //        	System.err.println(v+" inedges are "+graph1.getInEdges(v));
    //        	System.err.println(v+" incidentedges are "+graph1.getIncidentEdges(v));
    //        }

    String testFilename = "mtest.net";
    String testFilename2 = testFilename + "2";

    // assign arbitrary locations to each vertex
    Map<Number, Point2D> locations = new HashMap<Number, Point2D>();
    for (Number v : graph1.getVertices()) {
      locations.put(v, new Point2D.Double(v.intValue() * v.intValue(), 1 << v.intValue()));
    }
    Function<Number, Point2D> vld = Functions.forMap(locations);

    PajekNetWriter<Number, Number> pnw = new PajekNetWriter<Number, Number>();
    pnw.save(graph1, testFilename, gl, Functions.forMap(nr), vld);

    Graph<Number, Number> graph2 = pnr.load(testFilename, graphFactory);
    Function<Number, String> pl = pnr.getVertexLabeller();
    List<Number> id2 = new ArrayList<Number>(graph2.getVertices());
    Function<Number, Point2D> vld2 = pnr.getVertexLocationTransformer();

    assertEquals(graph1.getVertexCount(), graph2.getVertexCount());
    assertEquals(graph1.getEdgeCount(), graph2.getEdgeCount());

    // test vertex labels and locations
    for (int i = 0; i < graph1.getVertexCount(); i++) {
      Number v1 = id.get(i);
      Number v2 = id2.get(i);
      assertEquals(gl.apply(v1), pl.apply(v2));
      assertEquals(vld.apply(v1), vld2.apply(v2));
    }

    // test edge weights
    Function<Number, Number> nr2 = pnr.getEdgeWeightTransformer();
    for (Number e2 : graph2.getEdges()) {
      Pair<Number> endpoints = graph2.getEndpoints(e2);
      Number v1_2 = endpoints.getFirst();
      Number v2_2 = endpoints.getSecond();
      Number v1_1 = id.get(id2.indexOf(v1_2));
      Number v2_1 = id.get(id2.indexOf(v2_2));
      Number e1 = graph1.findEdge(v1_1, v2_1);
      assertNotNull(e1);
      assertEquals(nr.get(e1).floatValue(), nr2.apply(e2).floatValue(), 0.0001);
    }

    pnw.save(graph2, testFilename2, pl, nr2, vld2);

    compareIndexedGraphs(graph1, graph2);

    pnr.setVertexLabeller(null);
    Graph<Number, Number> graph3 = pnr.load(testFilename2, graphFactory);

    compareIndexedGraphs(graph2, graph3);

    File file1 = new File(testFilename);
    File file2 = new File(testFilename2);

    Assert.assertTrue(file1.length() == file2.length());
    file1.delete();
    file2.delete();
  }