Java HashMap size() Example

The size() method of java.util.HashMap class will returns the number of key-value mappings in this map.

Signature

public int size()

This method returns the number of key-value mappings in this map.

Example

The following example shows the usage of java.util.HashMap.size() method.

import java.util.HashMap;
import java.util.Map;

public class SizeMethodHashMapExample 
{
    public static void main(String args[])
    {
        // create an empty HashMap
        HashMap<Integer,String> hashMap1 = new HashMap<Integer,String>();
        
        // use put() method to put elements to the HashMap1
        hashMap1.put(1,"Element1");
        hashMap1.put(2,"Element2");
        hashMap1.put(3,"Element3");
        hashMap1.put(4,"Element4");
        hashMap1.put(5,"Element5");
        
        System.out.println("** Size of hashMap1 is : \""+hashMap1.size()+"\"");
        System.out.println("**Elements of hashMap1**");
        
        //Print the elements of hashMap1
        for (Map.Entry<Integer,String> entry : hashMap1.entrySet())
        {
            System.out.println("Key : "+entry.getKey()+" Value : "+entry.getValue());
        }
        
       
    }
}

Output

** Size of hashMap1 is : "5"
**Elements of hashMap1**
Key : 1 Value : Element1
Key : 2 Value : Element2
Key : 3 Value : Element3
Key : 4 Value : Element4
Key : 5 Value : Element5

Leave a Reply

Your email address will not be published. Required fields are marked *