package coreJava.com.shindo.corejava.map;import java.util.ArrayList;import java.util.Collections;import java.util.Comparator;import java.util.HashMap;import java.util.List;import java.util.Map;import java.util.Map.Entry;public class MapSort {    /**     *      * @Title: sortMap     * @Description: 对集合内的数据按key的字母顺序做排序     */    public List<Map.Entry<String, String>> sortMap(final Map<String, String> map) {        final List<Map.Entry<String, String>> infos = new ArrayList<Map.Entry<String, String>>(map.entrySet());        // 重写集合的排序方法：按字母顺序        Collections.sort(infos, new Comparator<Map.Entry<String, String>>() {            @Override            public int compare(final Entry<String, String> o1, final Entry<String, String> o2) {                return (o1.getKey().toString().compareTo(o2.getKey()));            }        });        return infos;    }    public static void main(final String[] args) {        final Map<String, String> map = new HashMap<String, String>();        map.put("charSet", "utf-8");        map.put("merId", "5412");        map.put("acqId", "321");        final List<Map.Entry<String, String>> list = new MapSort().sortMap(map);        for (final Map.Entry<String, String> m : list) {            System.out.println(m.getKey() + ":" + m.getValue());        }    }}

acqId:321charSet:utf-8merId:5412