Gremlin查询以获取两个顶点之间的边

Question

Trying something like this

List<Edge> result = g.traversal().V().hasLabel("contextlabel").where(__.otherV().hasLabel(labelName)).bothE().toList();

But getting below error org.apache.tinkerpop.gremlin.orientdb.OrientVertex cannot be cast to org.apache.tinkerpop.gremlin.structure.Edge

Answer 1

You're getting that error because V() returns an Vertex and then you try to filter with where() which takes that Vertex as the incoming item in the stream to evaluate. It tries to call otherV() which isn't an available method for a Vertex ...that method is meant for an edge. I think that you just have the bothE() in the wrong place and therefore

g.V().hasLabel("contextlabel").
  bothE().
  where(__.otherV().hasLabel(labelName)).