java统计List中的元素重复出现的次数和对map按key或键值排序

package cn.php;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

public class CountList {
	public static void main(String[] args) {
		List<String> strs = Arrays.asList("a", "b", "c", "d", "e", "a", "a",
				"a", "a", "b", "b", "b");
		Map<String, Integer> map = new HashMap<String, Integer>();
		Set<String> set = new HashSet<String>(strs);
		for (String str : set) {
			for (String lstr : strs) {
				if (str.equals(lstr)) {
					if (map.containsKey(str)) {
						Integer count = map.get(str);
						count++;
						map.put(str, count);
					} else {
						map.put(str, 1);
					}

				}
			}
		}
		//printMap(map);
		Map<String, Integer> sortMap = sortMapByValue(map);
		printMap(sortMap);
	}

	private static Map<String,Integer> sortMapByValue(Map<String, Integer> map) {
		List<Map.Entry<String, Integer>> mapList = new ArrayList<Map.Entry<String, Integer>>(
				map.entrySet());
		Collections.sort(mapList, new Comparator<Map.Entry<String, Integer>>() {
			@Override
			public int compare(Entry<String, Integer> o1,
					Entry<String, Integer> o2) {
				return o1.getValue()-o2.getValue();
			}
		});
		Map<String,Integer> result = new LinkedHashMap<String,Integer>();
		for(Map.Entry<String, Integer> entry:mapList){
			result.put(entry.getKey(), entry.getValue());
		}
		return result;
	}

	public static void printMap(Map<String, Integer> map) {

		for (Map.Entry<String, Integer> entry : map.entrySet()) {
			System.out.println("Key : " + entry.getKey() + " Value : "
					+ entry.getValue());
		}

	}

}

	public Map<String, String> sortMapByKey(Map<String, String> oriMap) {
		if (oriMap == null || oriMap.isEmpty()) {
			return null;
		}
		Map<String, String> sortedMap = new TreeMap<String, String>(
				new Comparator<String>() {
					public int compare(String key1, String key2) {
						int intKey1 = 0, intKey2 = 0;
						try {
							intKey1 = getInt(key1);
							intKey2 = getInt(key2);
						} catch (Exception e) {
							intKey1 = 0;
							intKey2 = 0;
						}
						return intKey1 - intKey2;
					}
				});
		sortedMap.putAll(oriMap);
		return sortedMap;
	}

	private int getInt(String str) {
		int i = 0;
		try {
			Pattern p = Pattern.compile("^\\d+");
			Matcher m = p.matcher(str);
			if (m.find()) {
				i = Integer.valueOf(m.group());
			}
		} catch (NumberFormatException e) {
			e.printStackTrace();
		}
		return i;
	}