// Create a plan with 3 vertices: A, B, C
// A -> B, A -> C, B -> C
private DAGPlan createSamplerDAGPlan() {
LOG.info("Setting up dag plan");
DAGPlan dag = DAGPlan.newBuilder()
.setName("TestSamplerDAG")
.addVertex(
VertexPlan.newBuilder()
.setName("A")
.setProcessorDescriptor(TezEntityDescriptorProto.newBuilder().setClassName("A.class"))