public static void keySort() {
Map<String, String> map = new TreeMap<String, String>(new Comparator<String>() {
public int compare(String obj1, String obj2) {
// 降序排序
return obj2.compareTo(obj1);
}
});
map.put("3", "ccccc");
map.put("76", "aaaaa");
map.put("4", "bbbbb");
map.put("98", "ddddd");
Set<String> keySet = map.keySet();
Iterator<String> iter = keySet.iterator();
while (iter.hasNext()) {
String key = iter.next();
System.out.println(key + ":" + map.get(key));
}
}
public static void valueSort() {
Map<String, String> map = new TreeMap<String, String>();
map.put("98", "ddddd");
map.put("175", "bbbbb");
map.put("5", "aaaaa");
map.put("1", "ccccc");
// 这里将map.entrySet()转换成list
List<Map.Entry<String, String>> list = new ArrayList<Map.Entry<String, String>>(map.entrySet());
// 然后通过比较器来实现排序
Collections.sort(list, new Comparator<Map.Entry<String, String>>() {
// 升序排序
public int compare(Entry<String, String> o1, Entry<String, String> o2) {
return o1.getValue().compareTo(o2.getValue());
}
});
for (Map.Entry<String, String> mapping : list) {
System.out.println(mapping.getKey() + ":" + mapping.getValue());
}
}