The lastKey() method of SortedMap interface in Java is used to return the last or the greatest key currently in this map.
Syntax:
K lastKey()
Where, K is the type of key maintained by this Set.
Parameters: This function does not accepts any parameter.
Return Value: It returns the last or the greatest key currently in this map
Exception: It throws NoSuchElementException, if this map is empty.
Below programs illustrate the above method:
Program 1:
// A Java program to demonstrate// working of SortedSetimport java.util.*;  public class Main {    public static void main(String[] args)    {        // Create a TreeSet and inserting elements        SortedMap<Integer, String> mp = new TreeMap<>();          // Adding Element to SortedSet        mp.put(1, "One");        mp.put(2, "Two");        mp.put(3, "Three");        mp.put(4, "Four");        mp.put(5, "Five");          // Returning the last key from the map        System.out.print("Last Key in the map is : "                         + mp.lastKey());    }} |
Output:
Last Key in the map is : 5
Program 2:
// A Java program to demonstrate// working of SortedSetimport java.util.*;  public class Main {    public static void main(String[] args)    {        // Create a TreeSet and inserting elements        SortedMap<String, String> mp = new TreeMap<>();          // Adding Element to SortedSet        mp.put("One", "Geeks");        mp.put("Two", "For");        mp.put("Three", "Geeks");        mp.put("Four", "Code");        mp.put("Five", "It");          // Returning the last key from the map        System.out.print("Last Key in the map is : "                         + mp.lastKey());    }} |
Output:
Last Key in the map is : Two
Reference: https://docs.oracle.com/javase/10/docs/api/java/util/SortedMap.html#lastKey()
