How to use a Comparator with a TreeMap in Java?

Question

I have a TreeMap that I want to sort by increasing or decreasing values. How?

Answer 1

Not really, set removes duplicates.

import java.util.*;

public class Program
{
public static void main(String[] args) {

boolean ascending = false;

SortedMap<String, String> sortedmap = new TreeMap<String, String>(ascending ? Comparator.naturalOrder() : Comparator.reverseOrder());

sortedmap.put("a", "t");
sortedmap.put("b", "b");
sortedmap.put("c", "t");
sortedmap.put("d", "s");
sortedmap.put("e", "x");

System.out.println(sortedmap);
}
}

Would this solution satisfy you?

Btw, just for the clarification purpose, do you want to sort your collection by key or value?
https://stackoverflow.com/questions/12947088/java-treemap-comparator - this thread might contain the answer to your question. Seems like Comparators should be used only for keys.

Answer 2

https://code.sololearn.com/cwsSlxW4scge/?ref=app

https://stackoverflow.com/questions/12947088/java-treemap-comparator

Answer 3

Will this work, if some values are equal?

Answer 4

Ok thanks