{
TriplesMapGraph copyGraph = graph.copyGraph();
if(null == strategy) {
strategy = new SteinerTreeRootStrategy(new WorksheetDepthRootStrategy());
}
copyGraph.killTriplesMap(tripleMapToKill, strategy);
copyGraph.stopTriplesMap(tripleMapToStop, strategy);
copyGraph.killPredicateObjectMap(POMToKill, strategy);
try{
DFSTriplesMapGraphDAGifier dagifier = new DFSTriplesMapGraphDAGifier();