我试图按值对rdd进行排序，如果多个值相等，则需要按字典顺序按键对这些值进行排序。
代码：

JavaPairRDD <String,Long> rddToSort = rddMovieReviewReducedByKey.mapToPair(new PairFunction < Tuple2 < String, MovieReview > , String, Long > () {

    @Override
    public Tuple2 < String, Long > call(Tuple2 < String, MovieReview > t) throws Exception {
        return new Tuple2 < String, Long > (t._1, t._2.count);
    }
});

到目前为止，我所做的是，使用 takeOrdered 并提供 CustomComperator ，但自从 takeOrdered 无法处理大量数据，当运行它不断退出的代码时（它占用了操作系统无法处理的大量内存）：

List < Tuple2 < String, Long >> rddSorted = rddMovieReviewReducedByKey.mapToPair(new PairFunction < Tuple2 < String, MovieReview > , String, Long > () {

    @Override
    public Tuple2 < String, Long > call(Tuple2 < String, MovieReview > t) throws Exception {
        return new Tuple2 < String, Long > (t._1, t._2.count);
    }
}).takeOrdered(newTopMovies, MapLongValueComparator.VALUE_COMP);

竞争对手：

static class MapLongValueComparator implements Comparator < Tuple2 < String, Long >> , Serializable {
        private static final long serialVersionUID = 1L;

        private static final MapLongValueComparator VALUE_COMP = new MapLongValueComparator();

        @Override
        public int compare(Tuple2 < String, Long > o1, Tuple2 < String, Long > o2) {
            if (o1._2.compareTo(o2._2) == 0) {
                return o1._1.compareTo(o2._1);
            }
            return -o1._2.compareTo(o2._2);
        }
}

错误：

16/06/30 21:09:23 INFO scheduler.DAGScheduler: Job 18 failed: takeOrdered at MovieAnalyzer.java:708, took 418.149182 s

这个rdd你怎么分类？你打算怎么办 TopKMovies 考虑值，如果相等，按字典顺序键。
谢谢。