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Java program to get the size of the HashMap collection

Given a HashMap collection, we have to get the size of it.
Submitted by Nidhi, on June 11, 2022

Problem statement

In this program, we will create a collection of key/value pair information using the HashMap collection. Then we will get the size of the HashMap collection using the size() method.

Source Code

The source code to get the size of the HashMap collection is given below. The given program is compiled and executed successfully.

// Java program to get the size of the 
// HashMap collection

import java.util.*;

public class Main {
  public static void main(String[] args) {
    HashMap < Integer, String > emp = new HashMap < > ();

    emp.put(101, "Amit");
    emp.put(102, "Arun");
    emp.put(103, "Akash");
    emp.put(104, "Ram");
    emp.put(105, "Mohan");

    System.out.println("Size of HashMap 'emp' is: " + emp.size());
  }
}

Output

Size of HashMap 'emp' is: 5

Explanation

In the above program, we imported the "java.util.*" package to use the HashMap class. Here, we created a public class Main.

The Main class contains a main() method. The main() method is the entry point for the program. And, created an object of the HashMap class and store the employee information using the put() method. Then we get the size of the HashMap collection using the size() method and printed the result.

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