java Comparator为什么没完成排序？

问题描述

问 题

            int top = Integer.parseInt(map.get("top"));
            List<NovelNews> novelNewsList = NovelMongo.GetAllNovel();
            Collections.sort(novelNewsList, new Comparator() {
                public int compare(Object obj0, Object obj1) {
                    NovelNews novel0 = (NovelNews) obj0;
                    NovelNews novel1 = (NovelNews) obj1;
                    return Long.toString(novel1.getHeat()).compareTo(Long.toString(novel0.getHeat()));
                }
            });
                        
            for(int i = 0; i <= top - 1; i++){
                System.out.println(novelNewsList.get(i).getHeat());                
            }

解决方案

...
return Long.toString(novel1.getHeat()).compareTo(Long.toString(novel0.getHeat()));

String.compareTo(String arg);是按照字典排序的规则，而不是比较值的大小,示例如下：
23
2231
223
123
想要按照Long型值的大小排序：

...
return novel0.getHeat().compareTo(novel1.getHeat());

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