@Override
    public LinkDataDuplexMap select(List<Application> sourceApplications, TimeWindow timeWindow, int outSearchDepth, int inSearchDepth) {
        return select(sourceApplications, timeWindow, outSearchDepth, inSearchDepth, false);
    }
Breadth-first link search
not thread safe

@author emeroad
@author minwoo.jung
@author HyunGil Jeong
web/src/main/java/com/navercorp/pinpoint/web/applicationmap/map/BidirectionalLinkSelector.java