多因子排序

 當需要對多因子進行排序時，可以構造下面這樣的包裝類，對List<YourObject>進行排序，假設排序因子都是Double類型的。如有其他需要，也可使用泛型。

/**
 * 用於多因子優先級排序
 * 要求List<YourObjectWrapper>的所有元素都是按照同樣因子優先級順序構造的scores
 */
class YourObjectWrapper implements Comparable<YourObjectWrapper> {
    private YourObject yourObject;
    /**
     * 排序因子，下標越小的優先級越高
     * 任一排序因子比出大小則返回結果，相同則繼續比較下一個排序因子
     */
    private List<Double> scores;

    @Override
    public int compareTo(YourObjectWrapper yourObjectWrapper) {
        if (CollectionUtils.isEmpty(yourObjectWrapper.getScores())) {
            return -1;
        }
        if (CollectionUtils.isEmpty(scores)) {
            return 1;
        }
        for (int i = 0; i < Math.min(scores.size(), yourObjectWrapper.getScores().size()); i++) {
            if (null == yourObjectWrapper.getScores().get(i)) {
                return -1;
            }
            if (null == scores.get(i)) {
                return 1;
            }
            if (scores.get(i) > yourObjectWrapper.getScores().get(i)) {
                return -1;
            } else if (scores.get(i) < yourObjectWrapper.getScores().get(i)) {
                return 1;
            }
        }
        if (scores.size() > yourObjectWrapper.getScores().size()) {
            return -1;
        } else if (scores.size() == yourObjectWrapper.getScores().size()) {
            return 0;
        }
        return 1;
    }

    public List<Double> getScores() {
        return scores;
    }

    public void setScores(List<Double> scores) {
        this.scores = scores;
    }

    public void setGoods(YourObject yourObject) {
        this.yourObject = yourObject;
    }

    public YourObject getGoods() {
        return this.yourObject;
    }
}

class YourObject {}