@Override public Void visitOp(PhysicalOperator op, Wrapper wrapper) { if (op instanceof HasAffinity) { wrapper.addEndpointAffinity(((HasAffinity) op).getOperatorAffinity()); } Stats stats = wrapper.getStats(); stats.addCost(op.getCost()); for (PhysicalOperator child : op) { child.accept(this, wrapper); } return null; }