code: public ExceptionSet getEdgeExceptionSet(Edge edge) {
          CachedExceptionSet cachedExceptionSet = thrownExceptionSetMap.get(edge.getSource());
          return cachedExceptionSet.getEdgeExceptionSet(edge);
      }
docs: Get the set of exceptions that can be thrown on given edge. This should
  only be called after the analysis completes.
  
  @param edge
  the Edge
  @return the ExceptionSet