java中map排序

Map<String, Integer> map = new TreeMap<String, Integer>(); </p><p>map.put("j2se", 20);<br />map.put("j2ee", 10);<br />map.put("j2me", 30); </p><p>List<Map.Entry<String, Integer>> infoIds = new ArrayList<Map.Entry<String, Integer>>(<br />map.entrySet());<br />//排序前<br />for (int i = 0; i < infoIds.size(); i++) {<br />String id = infoIds.get(i).toString();<br />System.out.println(id);<br />}<br />//排序<br />Collections.sort(infoIds, new Comparator<Map.Entry<String, Integer>>() {<br />public int compare(Map.Entry<String, Integer> o1,<br />Map.Entry<String, Integer> o2) {<br />return (o2.getValue() - o1.getValue());<br />}<br />});<br />//排序後<br />for (int i = 0; i < infoIds.size(); i++) {<br />String id = infoIds.get(i).toString();<br />System.out.println(id);<br />}<br />排序前：<br />j2ee=10<br />j2me=30<br />j2se=20<br />排序後：<br />j2me=30<br />j2se=20<br />j2ee=10