Java TreeMap.floorEntry(K key) example

In this java tutorial, You will learn how to use floorEntry(K key) method of TreeMap class.Thids method returns a key-value mapping associated with the greatest key less than or equal to the given key, or null if there is no such key.

Returns a key-value mapping associated with the greatest key less than or equal to the given key, or null if there is no such key.

syntax

public Map.Entry<K,V> floorEntry(K key)

Parameters

key - the key.

Returns

An entry with the greatest key less than or equal to key, or null if there is no such key.

Throws

ClassCastException - If the specified key cannot be compared with the keys currently in the map.

NullPointerException - if the specified key is null and this map uses natural ordering, or its comparator does not permit null keys.

Java TreeMap floorEntry(K key) example

  • Create TreeMap instance new TreeMap < Integer, String > ();
  • Add few elements in TreeMap e.g. students.put(1, "Pooja");
  • students.floorEntry(6); It will returns a key-value mapping associated (4=Aditi) with the greatest key less than or equal to the given key (6).
package com.technicalkeeda;

import java.util.TreeMap;

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

        TreeMap < Integer, String > students = new TreeMap < Integer, String > ();

        students.put(1, "Pooja");
        students.put(2, "Ajit");
        students.put(3, "Yashwant");
        students.put(4, "Aditi");

        System.out.println("floor entry:- " + students.floorEntry(6));

    }
}

output

floor entry:- 4=Aditi