I am relatively new to Java, and often find that I need to sort a Map<Key, Value>
on the values.
Since the values are not unique, I find myself converting the keySet
into an array
, and sorting that array through array sort with a custom comparator that sorts on the value associated with the key.
Is there an easier way?
Here's a generic-friendly version:
public class MapUtil {
public static <K, V extends Comparable<? super V>> Map<K, V> sortByValue(Map<K, V> map) {
List<Entry<K, V>> list = new ArrayList<>(map.entrySet());
list.sort(Entry.comparingByValue());
Map<K, V> result = new LinkedHashMap<>();
for (Entry<K, V> entry : list) {
result.put(entry.getKey(), entry.getValue());
}
return result;
}
}