if (stack.size() < 2 || !(stack.get(stack.size() - 2) instanceof DummyStoreOperator)) {
context.currentMergeJoinOperator = mergeJoinOp;
return null;
}
TezWork tezWork = context.currentTask.getWork();
@SuppressWarnings("unchecked")
Operator<? extends OperatorDesc> parentOp =
(Operator<? extends OperatorDesc>) ((stack.get(stack.size() - 2)));
// Guaranteed to be just 1 because each DummyStoreOperator can be part of only one work.
BaseWork parentWork = context.childToWorkMap.get(parentOp).get(0);
// we need to set the merge work that has been created as part of the dummy store walk. If a
// merge work already exists for this merge join operator, add the dummy store work to the
// merge work. Else create a merge work, add above work to the merge work
MergeJoinWork mergeWork = null;
if (context.opMergeJoinWorkMap.containsKey(mergeJoinOp)) {
// we already have the merge work corresponding to this merge join operator
mergeWork = context.opMergeJoinWorkMap.get(mergeJoinOp);
} else {
mergeWork = new MergeJoinWork();
tezWork.add(mergeWork);
context.opMergeJoinWorkMap.put(mergeJoinOp, mergeWork);
}
mergeWork.setMergeJoinOperator(mergeJoinOp);
mergeWork.addMergedWork(null, parentWork);
tezWork.setVertexType(mergeWork, VertexType.MULTI_INPUT_UNINITIALIZED_EDGES);
for (BaseWork grandParentWork : tezWork.getParents(parentWork)) {
parentWork.setName(grandParentWork.getName());
TezEdgeProperty edgeProp = tezWork.getEdgeProperty(grandParentWork, parentWork);
tezWork.disconnect(grandParentWork, parentWork);
tezWork.connect(grandParentWork, mergeWork, edgeProp);
}
for (BaseWork childWork : tezWork.getChildren(parentWork)) {
TezEdgeProperty edgeProp = tezWork.getEdgeProperty(parentWork, childWork);
tezWork.disconnect(parentWork, childWork);
tezWork.connect(mergeWork, childWork, edgeProp);
}
tezWork.remove(parentWork);
DummyStoreOperator dummyOp = (DummyStoreOperator) (stack.get(stack.size() - 2));
parentWork.setTag(mergeJoinOp.getTagForOperator(dummyOp));