Map<Rule, NodeProcessor> opRules = new LinkedHashMap<Rule, NodeProcessor>();
opRules.put(new RuleRegExp("R1", "(TS%FIL%)|(TS%FIL%FIL%)"),
OpProcFactory.getFilterProc());
// The dispatcher fires the processor corresponding to the closest matching rule and passes the context along
Dispatcher disp = new DefaultRuleDispatcher(OpProcFactory.getDefaultProc(), opRules, opWalkerCtx);
GraphWalker ogw = new DefaultGraphWalker(disp);
// Create a list of topop nodes
ArrayList<Node> topNodes = new ArrayList<Node>();
topNodes.addAll(pctx.getTopOps().values());