TreeMap2.java

import java.util.Comparator;
import java.util.TreeMap;
import java.util.Map.Entry;
public class TreeMap2 {
    int no;
    String name;
    int value;
    TreeMap2(int no, String name, int value) {
        this.no = no;
        this.name = name;
        this.value = value;
        System.out.println("TreeMap2: " + no + " " + name + " " + value);
    }

    @Override
    public String toString() {
        return this.no + " " + this.name + " "
                + this.value;
    }
}

class CompareToTreeMap implements Comparator<TreeMap2> {

    @Override
    public int compare(TreeMap2 o1, TreeMap2 o2) {
        System.out.println(" ");
        System.out.println("o1.value:" + o1.value );
        System.out.println("o2.value:" + o2.value);
        System.out.println("o1.value-o2.value:" + (o1.value-o2.value));
        System.out.println(" ");
        return  o1.value-o2.value;
    } 
    
}

 class newTreeMap2 {

    
    public static void main(String[] args) {
        TreeMap<TreeMap2, String> tree_map = new TreeMap<>(new CompareToTreeMap());
        tree_map.put(new TreeMap2(1, "one", 1), "one");
        tree_map.put(new TreeMap2(2, "two", 2), "two");
        tree_map.put(new TreeMap2(3, "three", 3), "three");
        tree_map.put(new TreeMap2(4, "four", 4), "four");
        tree_map.put(new TreeMap2(5, "five", 5), "five");
        tree_map.put(new TreeMap2(6, "six", 6), "six");
        System.out.println("TreeMap: " + tree_map);

        for (Entry<TreeMap2, String> entry : tree_map.entrySet()) {
            System.out.println("Key: " + entry.getKey() + " Value: " + entry.getValue());
        }
    }
}