@Override public int compare(WordSimilarity o1, WordSimilarity o2) { if (Double.isNaN(o1.getSimilarity()) && Double.isNaN(o2.getSimilarity())) { return 0; } else if (Double.isNaN(o1.getSimilarity()) && !Double.isNaN(o2.getSimilarity())) { return -1; } else if (!Double.isNaN(o1.getSimilarity()) && Double.isNaN(o2.getSimilarity())) { return 1; } return Double.compare(o2.getSimilarity(), o1.getSimilarity()); }