Method depthFirst

src/org/apache/pig/newplan/DepthFirstWalker.java:56–69

(Operator node,
                            Collection<Operator> successors,
                            Set<Operator> seen,
                            PlanVisitor visitor)

    }

    private void depthFirst(Operator node,
                            Collection<Operator> successors,
                            Set<Operator> seen,
                            PlanVisitor visitor) throws FrontendException {
        if (successors == null) return;

        for (Operator suc : successors) {
            if (seen.add(suc)) {
                suc.accept(visitor);
                Collection<Operator> newSuccessors = Utils.mergeCollection(plan.getSuccessors(suc), plan.getSoftLinkSuccessors(suc));
                depthFirst(suc, newSuccessors, seen, visitor);
            }
        }
    }
}