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;
}