JUNG get all target vertex labels from the Cluster

Question

at the moment, I'm searching for a possibility to get all targets Vertex labels of one cluster. I'm using the radial layout and i know the function's getEdgeTargets and getEdgeSource. But How can i find all targets Vertex labels in multiple clusters.

for(int i = 0; i < 100; i++)
    { // check the last added cluster the edge count. Because edge count = Nodes Count
        if(cluster.graph.containsEdge(cluster.graph.getEdge(nodesList.get(nodesList.size()-1).getNodename() ,cluster.graph.getEdgeTarget(i)))&&
            Nodecnt <   cluster.graph.getEdge(nodesList.get(nodesList.size()-1).getNodename() ,cluster.graph.getEdgeTarget(i)))
        {
            Nodecnt = cluster.graph.getEdge(nodesList.get(nodesList.size()-1).getNodename() ,cluster.graph.getEdgeTarget(i));

        }
    }