java使用treemap做词频统计wordcount(字母排序alphabet和词频排序descending freq.)

import java.util.*;

public class Test {

    static List> getWordInDescendingFreqOrder(Map wordCount) {

        // Convert map to list of  entries
        List> list =
                new ArrayList<>(wordCount.entrySet());

        // Sort list by integer values
        Collections.sort(list, new Comparator>() {
            public int compare(Map.Entry o1, Map.Entry o2) {
                // compare o2 to o1, instead of o1 to o2, to get descending freq. order
                return (o2.getValue()).compareTo(o1.getValue());
            }
        });

        return list;
    }

    public static void main(String[] args) {

        // format article to simple words
        String article = Test.article
                .replace("'", "")
                .replace("’", "")
                .replace("?", " ")
                .replace("!", " ")
                .replace("“"," ")
                .replace("”"," ")
                .replace(";", " ")
                .replace(",", " ")
                .replace(".", " ")
                .replace("\n", " ");
        System.out.println("words to be sorted:\n" + article + "\n");

        //tree map sort by alphabet
        String[] words = article.split("\\s+");
        TreeMap wordCount = new TreeMap<>();

        for (String word : words) {
            Integer count = wordCount.get(word);
            if (count == null) {
                wordCount.put(word, 1);
            } else {
                wordCount.put(word, count + 1);
            }
        }

        System.out.println("word count alphabet sort:");
        for (String key : wordCount.keySet()) {
            System.out.println(key + "-" + wordCount.get(key));
        }

        System.out.println("\nword count descend sort:");
        List> wordCountDescend = Test.getWordInDescendingFreqOrder(wordCount);
        for (Map.Entry one : wordCountDescend) {
            System.out.println(one.getKey() + "-" + one.getValue());
        }

    }

    public static String article = "It is no mean feat to be one of the top-ten trending hashtags on Weibo, China’s equivalent of Twitter, for 20 consecutive days and counting. “All is Well”, a show on provincial television which premiered on March 1st, has done just that. The show tells the story of a fictional Chinese family torn by internal conflict. The female protagonist, Su Mingyu, is barely on speaking terms with her widowed father and one of her two brothers. The father is a nagging crank who expects his two adult sons to bankroll his lavish tastes. This leads to constant bickering between the brothers, neither of whom wants to be called unfilial.";

}