Java DefaultDirectedGraph.addEdge方法代碼示例

import org.jgrapht.graph.DefaultDirectedGraph; //導入方法依賴的package包/類
/**
 * Returns a reverted version of this graph in a jGraph
 *
 * That is a graph containing exactly the same nodes as this one but for
 * each edge from v1 to v2 in this graph the resulting graph will contain an
 * edge from v2 to v1 - or in other words the reverted edge
 *
 * This is used to revert CFGs in order to determine control dependencies
 * for example
 *
 * @return a {@link org.jgrapht.graph.DefaultDirectedGraph} object.
 */
protected DefaultDirectedGraph<V, E> computeReverseJGraph() {

	DefaultDirectedGraph<V, E> r = new DefaultDirectedGraph<V, E>(edgeClass);

	for (V v : vertexSet())
		if (!r.addVertex(v))
			throw new IllegalStateException(
					"internal error while adding vertices");

	for (E e : edgeSet()) {
		V src = getEdgeSource(e);
		V target = getEdgeTarget(e);
		if (r.addEdge(target, src) == null)
			throw new IllegalStateException(
					"internal error while adding reverse edges");
	}

	return r;
}
 

import org.jgrapht.graph.DefaultDirectedGraph; //導入方法依賴的package包/類
private DefaultDirectedGraph<Node, DefaultEdge> asGraph(Set<Triple> triples) {
	DefaultDirectedGraph<Node, DefaultEdge> graph = new DefaultDirectedGraph<>(DefaultEdge.class);
	for (Triple triple : triples) {
		// we have to omit type triples to get connected subgraphs later on
		if (!triple.predicateMatches(RDF.type.asNode())) {
			graph.addVertex(triple.getSubject());
			graph.addVertex(triple.getObject());
			graph.addEdge(triple.getSubject(), triple.getObject());
		}
	}
	return graph;
}
 

import org.jgrapht.graph.DefaultDirectedGraph; //導入方法依賴的package包/類
public void testCycleDetection() {
    DefaultDirectedGraph<String, Object> g = new DefaultDirectedGraph<String, Object>(Object.class);

    // Add vertices, e.g. equations.
    g.addVertex("A");
    g.addVertex("B");
    g.addEdge("A", "B");

    g.addVertex("D");
    g.addVertex("A");
    g.addEdge("D", "A");

    g.addVertex("B");
    g.addVertex("C");
    g.addEdge("B", "C");

    g.addVertex("G");
    g.addVertex("H");
    g.addEdge("G", "H");

    g.addVertex("C");
    g.addVertex("D");
    g.addEdge("C", "D");

    System.out.println(g.toString());

    // Are there cycles in the dependencies.
    CycleDetector<String, Object> cycleDetector = new CycleDetector<String, Object>(g);
    // Cycle(s) detected.
    if (cycleDetector.detectCycles()) {

        System.out.println("Cycles detected.");

        // Get all vertices involved in cycles.
        Set<String> cycleVertices = cycleDetector.findCycles();

        // Loop through vertices trying to find disjoint cycles.
        while (!cycleVertices.isEmpty()) {
            System.out.println("Cycle:");

            // Get a vertex involved in a cycle.
            Iterator<String> iterator = cycleVertices.iterator();
            String cycle = iterator.next();

            // Get all vertices involved with this vertex.
            Set<String> subCycle = cycleDetector.findCyclesContainingVertex(cycle);
            for (String sub : subCycle) {
                System.out.println("   " + sub);
                // Remove vertex so that this cycle is not encountered
                // again.
                cycleVertices.remove(sub);
            }
        }
    }

    // No cycles.  Just output properly ordered vertices.
    else {
        TopologicalOrderIterator<String, Object> orderIterator = new TopologicalOrderIterator<String, Object>(g);
        System.out.println("\nOrdering:");
        while (orderIterator.hasNext()) {
            String v = orderIterator.next();
            System.out.println(v);
        }
    }
}
 

import org.jgrapht.graph.DefaultDirectedGraph; //導入方法依賴的package包/類
private void link(DefaultDirectedGraph<FStream, IndexedEdge<FStream>> G, FStream node, FStream n) {
	// The source should be there, the destination we'll add if necessary.
	if (!G.containsVertex(n)) {
		G.addVertex(n);
	}
	
	index_counter += 1;
	IndexedEdge<FStream> e = new IndexedEdge<FStream>(node, n, index_counter);
	G.addEdge(node, n, e);
}
 

import org.jgrapht.graph.DefaultDirectedGraph; //導入方法依賴的package包/類
private void worker(DefaultDirectedGraph<TaskId, DefaultEdge> graph, Task task, TaskId parentId, ImmutableMap.Builder<TaskId, Task> tasksBuilder, Set<TaskId> usedTasksSet)
{
    if ( usedTasksSet.add(task.getTaskId()) )
    {
        tasksBuilder.put(task.getTaskId(), task);
    }

    graph.addVertex(task.getTaskId());
    if ( parentId != null )
    {
        graph.addEdge(parentId, task.getTaskId());
    }
    task.getChildrenTasks().forEach(child -> worker(graph, child, task.getTaskId(), tasksBuilder, usedTasksSet));
}
 

import org.jgrapht.graph.DefaultDirectedGraph; //導入方法依賴的package包/類
/**
 * Rigourous Test :-)
 */
public void testDFS() {

	DefaultDirectedGraph<Vertex, Double> graph = new DefaultDirectedGraph<Vertex, Double>(
			Double.class);
	Vertex v = null;
	for (int i = 0; i < this.numOfVertices; i++) {
		v = new Vertex("v" + i);
		graph.addVertex(v);
	}

	Vertex lastVertex = v;

	Set<Vertex> vertices = graph.vertexSet();

	Random rand = new Random();
	Double nextEdge = 0.0;
	for (Vertex start : vertices)
		for (Vertex end : vertices)
			if (!start.equals(end) && !graph.containsEdge(start, end)) {
				nextEdge = rand.nextDouble();
				if (nextEdge > 0.9)
					graph.addEdge(start, end, nextEdge);
			}

	System.out.println("Vertices: " + vertices.size());
	System.out.println("Edges: " + graph.edgeSet().size());

	DepthFirstIterator<Vertex, Double> dfsIter = new DepthFirstIterator<Vertex, Double>(
			graph, lastVertex);

	DFS<Double> dfs = new DFS<Double>(graph);
	Vertex[] dfsResult = dfs.depthFirstTree(lastVertex);

	for (int i = 0; i < this.numOfVertices && dfsIter.hasNext(); i++) {
		System.out.println(dfsResult[i] + " " + dfsIter.next());
	}
}
 

import org.jgrapht.graph.DefaultDirectedGraph; //導入方法依賴的package包/類
/**
 Test creating a directed graph, checking it for cycles and either
 outputting cycle information or ordering.

 @param createCycles true - create a directed graph which contains
 cycles.  false - create a directed graph which does not contain
 any cycles.
 */
public static void test(boolean createCycles) {
   DefaultDirectedGraph<String, DefaultEdge> g;

   g = new DefaultDirectedGraph<String, DefaultEdge>(
      DefaultEdge.class);

   // Add vertices, e.g. equations.
   g.addVertex("a");
   g.addVertex("b");
   g.addVertex("c");
   g.addVertex("d");
   g.addVertex("e");

   // Add edges, e.g. dependencies.
   // 2 cycles,
   //    a = f(b)
   //    b = f(c)
   //    c = f(a)
   // and
   //    d = f(e)
   //    e = f(d)
   g.addEdge("b", "a");
   g.addEdge("c", "b");
   if (createCycles) {
      g.addEdge("a", "c");
      g.addEdge("a", "d");
   }
   g.addEdge("e", "d");
   if (createCycles) {
      g.addEdge("d", "e");
   }

   System.out.println(g.toString());

   displayCyclesInfo(g);
}
 

import org.jgrapht.graph.DefaultDirectedGraph; //導入方法依賴的package包/類
/**
    Generate two cases, one with cycles, this is depencencies and one
    without.

    @param args Ignored.
    */
   public static void main(String [] args) {
//      System.out.println("\nCase 1: There are cycles.");
//      test(true);
//
//      System.out.println("\nCase 2: There are no cycles.");
//      test(false);
//
//      System.out.println("\nAll done");
//      System.exit(0);
	   
	   DefaultDirectedGraph<String, DefaultEdge> g;

	      g = new DefaultDirectedGraph<String, DefaultEdge>(DefaultEdge.class);

	      // Add vertices, e.g. equations.
	      g.addVertex("a");
	      g.addVertex("b");
	      g.addVertex("c");
	      g.addVertex("d");
	      
	      g.addVertex("x");
	      g.addVertex("y");
	      g.addVertex("z");

	      g.addEdge("a", "b");
	      g.addEdge("b", "c");
	      g.addEdge("c", "d");
	      g.addEdge("d", "a");
	      
	      g.addEdge("a", "x");
	      g.addEdge("x", "y");
	      g.addEdge("y", "z");
	      g.addEdge("z", "a");

	      System.out.println(g.toString());

	      displayCyclesInfo(g);
	   
   }
 

import org.jgrapht.graph.DefaultDirectedGraph; //導入方法依賴的package包/類
/**
 * Rigourous Test :-)
 */
public void testBFS() {

	DefaultDirectedGraph<Vertex, Double> graph = new DefaultDirectedGraph<Vertex, Double>(
			Double.class);
	Vertex v = null;
	for (int i = 0; i < this.numOfVertices; i++) {
		v = new Vertex("v" + i);
		graph.addVertex(v);
	}
	
	// use last vertex as start point of search
	Vertex lastVertex = v;

	Set<Vertex> vertices = graph.vertexSet();

	// add edges to graph
	Random rand = new Random();
	Double nextEdge = 0.0;
	for (Vertex start : vertices)
		for (Vertex end : vertices)
			if (!start.equals(end) && !graph.containsEdge(start, end)) {
				nextEdge = rand.nextDouble();
				if (nextEdge > 0.9)
					graph.addEdge(start, end, nextEdge);
			}

	System.out.println("Vertices: " + vertices.size());
	System.out.println("Edges: " + graph.edgeSet().size());

	BreadthFirstIterator<Vertex, Double> bfsIter = new BreadthFirstIterator<Vertex, Double>(
			graph, lastVertex);

	BFS<Double> bfs = new BFS<Double>(graph);
	Vertex[] bfsResult = bfs.breadthFirstTree(lastVertex);

	for (int i = 0; i < this.numOfVertices && bfsIter.hasNext(); i++) {
		System.out.println(bfsResult[i] + " " + bfsIter.next());
	}

}