Sorting HashMap by values in ascending and descending order

The below example shows Java program to sort a Map by values in ascending and descending order, you can see that it’s so easy to sort the Map.

public static void main(String args[]) {

Map < String, Integer > map = new HashMap < String, Integer > ();

map.put("A", 34);

map.put("B", 25);

map.put("C", 50);

map.put("D", 50); // "duplicate" value

System.out.println(entriesSortedByValues(map));

}

static < K, V extends Comparable < ? super V >> List < Entry < K, V >> entriesSortedByValues(Map < K, V > map) {

List < Entry < K, V >> sortedEntries = new ArrayList < Entry < K, V >> (map.entrySet());

Collections.sort(sortedEntries, new Comparator < Entry < K, V >> () {

@Override

public int compare(Entry < K, V > e1, Entry < K, V > e2) {

//return e1.getValue().compareTo(e2.getValue()); // if ascending order

return e2.getValue().compareTo(e1.getValue()); // if descending order

}

});

return sortedEntries;

}