Open In App
Related Articles

TreeMap size() Method in Java with Examples

Improve
Improve
Improve
Like Article
Like
Save Article
Save
Report issue
Report

size() method of TreeMap class is used to get the size of the map which refers to the number of the key-value pair or mappings in the Map.

--> java.util package
    --> TreeMap class
        --> size() Method   

Syntax: 

Tree_Map.size()

Return Value: The size of the map which also means the number of key-value pairs present in the map. 

Example 1: Mapping String Values to Integer Keys

Java

// Java Program to Illustrate size() Method
// of TreeMap class
 
// Importing required classes
import java.util.*;
 
// Main class
public class GFG {
 
    // Main driver method
    public static void main(String[] args)
    {
        // Creating an empty TreeMap by
        // declaring object of Integer, string pairs
        TreeMap<Integer, String> tree_map
            = new TreeMap<Integer, String>();
 
        // Mapping string values to int keys
        // using put() method
        tree_map.put(10, "Geeks");
        tree_map.put(15, "4");
        tree_map.put(20, "Geeks");
        tree_map.put(25, "Welcomes");
        tree_map.put(30, "You");
 
        // Displaying the elements of TreeMap
        System.out.println("Initial Mappings are: "
                           + tree_map);
 
        // Now displaying the size of this map
        // using size() method
        System.out.println("The size of the map is "
                           + tree_map.size());
    }
}

                    

Output: 
Initial Mappings are: {10=Geeks, 15=4, 20=Geeks, 25=Welcomes, 30=You}
The size of the map is 5

 

Example 2: Mapping Integer Values to String Keys

Java

// Java Program to Illustrate the size() method
// of TreeMap class
 
// Importing required classes
import java.util.*;
 
// Main class
public class GFG {
 
    // Main driver method
    public static void main(String[] args)
    {
        // Creating an empty TreeMap by
        // declaring object of string, integer pairs
        TreeMap<String, Integer> tree_map
            = new TreeMap<String, Integer>();
 
        // Mapping int values to string keys
        // using put() method
        tree_map.put("Geeks", 10);
        tree_map.put("4", 15);
        tree_map.put("Geeks", 20);
        tree_map.put("Welcomes", 25);
        tree_map.put("You", 30);
 
        // Printing the elements of TreeMap
        System.out.println("Initial Mappings are: "
                           + tree_map);
 
        // Printing the size of the map
        // using size() method
        System.out.println("The size of the map is "
                           + tree_map.size());
    }
}

                    

Output: 
Initial Mappings are: {4=15, Geeks=20, Welcomes=25, You=30}
The size of the map is 4

 

Note: The same operation can be performed with any type of Mappings with variation and combination of different data types.



Last Updated : 29 Nov, 2021
Like Article
Save Article
Previous
Next
Share your thoughts in the comments
Similar Reads