单词统计续

package paixu;
import java.io.BufferedReader;
import java.io.FileReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class p { 
            public static void main(String[] args) throws Exception {
                BufferedReader reader = new BufferedReader(new FileReader(
                        "D:\飘c1.txt"));
                StringBuffer buffer = new StringBuffer();
                String line = null;
                while ((line = reader.readLine()) != null) {
                    buffer.append(line);
                }
                reader.close();
                Pattern expression = Pattern.compile("[a-zA-Z]+");// 定义正则表达式匹配单词
                String string = buffer.toString();
                Matcher matcher = expression.matcher(string);//
                Map<String, Integer> map = new TreeMap<String, Integer>();
                String word = "";
                int times = 0;

  while (matcher.find()) {// 是否匹配单词
                    word = matcher.group();// 得到一个单词-树映射的键
                    if (map.containsKey(word)) {// 如果包含该键，单词出现过
                        times = map.get(word);// 得到单词出现的次数
                        map.put(word, times + 1);
                    } else {
                        map.put(word, 1);// 否则单词第一次出现，添加到映射中
                    }
                }
                /*
                 * 核心：如何按照TreeMap 的value排序而不是key排序.将Map.Entry放在集合里， 重写比较器，在用
                 * Collections.sort(list, comparator);进行 排序
                 */
         
                List<Map.Entry<String, Integer>> list = new ArrayList<Map.Entry<String, Integer>>(
                        map.entrySet());
                /*
                 * 重写比较器
                 * 取出单词个数（value）比较
                 */
                Comparator<Map.Entry<String, Integer>> comparator = new Comparator<Map.Entry<String, Integer>>() {
                    public int compare(Map.Entry<String, Integer> left,
                            Map.Entry<String, Integer> right) {
                        return (left.getValue()).compareTo(right.getValue());
                    }
                };
                Collections.sort(list, comparator);// 排序
                // 打印最多十个
                int last = list.size() - 1;
                for (int i = last; i > last - 10; i--) {
                    String key = list.get(i).getKey();
                    Integer value = list.get(i).getValue();
                    System.out.println(key + " :" + value);
                }
            }
        }