TreeMap按value值进行排序

import java.util.ArrayList;import java.util.Collections;import java.util.Comparator;import java.util.HashMap;import java.util.LinkedHashMap;import java.util.List;import java.util.Map;import java.util.TreeMap;public class CountAccurrenceOfWord {public static void main(String[] args) {String text = "Have a good day. Have a good class. Have a good visit. Have fun";Map<String, Integer> hashMap = new HashMap<String, Integer>();String[] words = text.split("[ .!?]");for (int i = 0; i < words.length; i++) {if (words[i].length() > 1) {if (hashMap.get(words[i]) != null) {int value = hashMap.get(words[i]).intValue();value++;hashMap.put(words[i], value);} elsehashMap.put(words[i], 1);}}Map<String, Integer> treeMap = new TreeMap<String, Integer>(hashMap);System.out.println("Dispaly words and their count in ascending order of the word");System.out.println(treeMap);List arrayList = new ArrayList(hashMap.entrySet());Collections.sort(arrayList, new Comparator(){public int compare(Object o1, Object o2) {Map.Entry obj1 = (Map.Entry) o1;Map.Entry obj2 = (Map.Entry) o2;return ((Integer) obj2.getValue()).compareTo((Integer)obj1.getValue());}});System.out.println(arrayList); }}