Java 到达分支中顶点的第n个后续顶点

我使用jgrapht库创建了一个有向图。我使用

successorListOf（）

方法访问顶点的后续对象，但我希望能够访问给定顶点的第n个后续对象（在我的例子中，这些是点对象）。我的有向图有两个分支（这里称为B和C）。我编写了一个简单而简短的代码，使之更容易：

public static DirectedGraph<Point, DefaultEdge> directedGraph = new DefaultDirectedGraph<Point, DefaultEdge>(DefaultEdge.class);
public static Point startPoint = new Point(2, 6, "S");
public static Point firstPoint = new Point(2, 7, "A");
public static Point secondPoint = new Point(2, 8, "B");
public static Point thirdPoint = new Point(2, 9, "B");
public static Point fourthPoint = new Point(2, 10, "B");
public static Point fifthPoint = new Point(3, 7, "C");
public static Point sixthPoint = new Point(4, 7, "C");
public static Point seventhPoint = new Point(5, 7, "C");


void setup ()  {
  directedGraph.addVertex(startPoint);
  directedGraph.addVertex(firstPoint);
  directedGraph.addVertex(secondPoint);
  directedGraph.addVertex(thirdPoint);
  directedGraph.addVertex(fourthPoint);
  directedGraph.addVertex(fifthPoint);
  directedGraph.addVertex(sixthPoint);
  directedGraph.addVertex(seventhPoint);
  directedGraph.addEdge(startPoint, firstPoint);
  directedGraph.addEdge(firstPoint, secondPoint);
  directedGraph.addEdge(firstPoint, thirdPoint);
  directedGraph.addEdge(firstPoint, fourthPoint);
}

// --------------------------------------------------------------
public static ArrayList<Point> pointList = new ArrayList<Point>();
public static class Point {

  public int x;
  public int y;
  public String iD;
  public  Point(int x, int y, String iD) 
  {

    this.x = x;
    this.y = y;
    this.iD= iD;
  }
  @Override
    public String toString() {
    return ("[x="+x+" y="+y+" iD="+iD+ "]");
  }

  @Override
    public int hashCode() {
    int hash = 7;
    hash = 71 * hash + this.x;
    hash = 71 * hash + this.y;

    return hash;
  }



  @Override
    public boolean equals(Object other) 
  {
    if (this == other)
      return true;

    if (!(other instanceof Point))
      return false;

    Point otherPoint = (Point) other;
    return otherPoint.x == x && otherPoint.y == y;
  }
}

我想使用：

for (Point successor : Graphs.successorListOf (directedGraph, firstPoint)) {
        if (successor.type.equals("B") {
               directedGraph.addEdge(firstPoint, successor);
        }
}

但在这里，我只能找到分支B的第一个继任者。在第n个继任者的情况下，我如何才能找到继任者的继任者等？B分支中的顶点数量可能会改变，这就是为什么我在寻找一种方法来自动实现这一点，而不是逐点进行

我怎么能这样做

在图纸上，1是我的起点，2是我的第一点，然后有两个分支，这两个分支将是我的B&C分支

---

我编写了以下代码，但它没有经过测试，您可能需要修改它以满足您的需求

这段代码使用您在提供的示例中使用的变量和实例将DFS（深度优先搜索）运行到预定义的深度

public void getSuccessor(DirectedGraph<Point, DefaultEdge> graph, Point point, String type, int depth) {
    List<Point> visitedPoints = new ArrayList<>();
    _getSuccessor(graph, point, visitedPoints, type, depth);
}

private void _getSuccessor(DirectedGraph<Point, DefaultEdge> graph, Point point, List<Point> visitedPoints, String type, int depth){

    if(depth == 0)
        return;

    // Mark node as visited
    visitedPoints.add(point);

    // Loop on all its successors
    for(Point successor : Graphs.successorListOf (directedGraph, point)){

        // If node not already visited
        if(!visitedPoints.contains(successor) && successor.type.equals(type)) {
            directedGraph.addEdge(firstPoint, successor);
            _getSuccessor(graph, successor, visitedPoints, type, depth-1);
        }
    }
}

public void getsuccession（DirectedGraph图形、点、字符串类型、整数深度）{
列出访问点=新建ArrayList（）；
_GetSuccession（图形、点、访问点、类型、深度）；
}
私有void _getsuccession（DirectedGraph图形、点、列表访问点、字符串类型、整数深度）{
如果（深度==0）
返回；
//将节点标记为已访问
访问点。添加（点）；
//在所有的继承者身上循环
for（点后继：Graphs.successorListOf（directedGraph，点））{
//如果节点尚未访问
如果（！visitedPoints.contains（succession）&&succession.type.equals（type））{
directedGraph.addEdge（第一点，后继点）；
_GetSuccession（图形、继任者、访问点、类型、深度-1）；
}
}
}

A顶点是否连接到B顶点？这就是“后继”的定义吗？你能提供你的图形的图像吗？@TimBiegeleisen当我使用“directedGraph.addEdge（firstPoint，secondPoint）；”添加边时secondPoint将是firstPoint的继任者。始终是括号末尾的点，它是括号开头点的后续点。所以唯一的点A是B和C的起始交点branches@CMPS我加了一张照片

public void getSuccessor(DirectedGraph<Point, DefaultEdge> graph, Point point, String type, int depth) {
    List<Point> visitedPoints = new ArrayList<>();
    _getSuccessor(graph, point, visitedPoints, type, depth);
}

private void _getSuccessor(DirectedGraph<Point, DefaultEdge> graph, Point point, List<Point> visitedPoints, String type, int depth){

    if(depth == 0)
        return;

    // Mark node as visited
    visitedPoints.add(point);

    // Loop on all its successors
    for(Point successor : Graphs.successorListOf (directedGraph, point)){

        // If node not already visited
        if(!visitedPoints.contains(successor) && successor.type.equals(type)) {
            directedGraph.addEdge(firstPoint, successor);
            _getSuccessor(graph, successor, visitedPoints, type, depth-1);
        }
    }
}