Sort map based on values in decreasing order

Question

 Map<Character, Integer> map = new HashMap();
        for(char c : ch) {
            if(map.get(c) == null) {
                map.put(c, 1);
            } else {
                map.put(c, map.get(c)+1);
            }
        }
        for(Map.Entry entry : map.entrySet()) {
            System.out.println("Key is  "+ entry.getKey() + "  Value is  " + entry.getValue());
        }

I have a String str = "PriyankaTaneja"

I want to count the frequency of characters in the String using map and i want to sort the map in decreasing order of values, that means the character repeating the max number of times should be the first to print.

Does this answer your question? [Sort ArrayList of custom Objects by property](https://stackoverflow.com/questions/2784514/sort-arraylist-of-custom-objects-by-property) — Anonymous Atom, Jul 03 '23 at 19:49

score 1 · Accepted Answer · answered Jul 03 '23 at 19:49

To sort a map by values in descending order, you can use the Java stream API and the Comparator interface. For example:

Map<Character, Integer> map = new HashMap<>();
for(char c : ch) {
  if(map.get(c) == null) {
      map.put(c, 1);
  } else {
    map.put(c, map.get(c)+1);
  }
}

Map<Character, Integer> sortedMap = map.entrySet()
  .stream()
  .sorted(Map.Entry.comparingByValue(Comparator.reverseOrder()))
  .collect(Collectors.toMap(
    Map.Entry::getKey,
    Map.Entry::getValue, 
    (e1, e2) -> e1,
    LinkedHashMap::new
  ));

for(Map.Entry entry : sortedMap.entrySet()) {
  System.out.println("Key is  "+ entry.getKey() + "  Value is  " + entry.getValue());
}

You're welcome. If you have any other questions, please let me know. — Pluto, Jul 03 '23 at 20:10

Sort map based on values in decreasing order

1 Answers1