Size of HashSet

Its very important to know the size of HashSet as it is required in most of the times while coding

We have size() method in HashSet class which helps us to determine the size of HashSet

Size is the number of elements in that HashSet

public int size()


Example :

  1. import java.util.*;
  2.  
  3. public class HashSetSize {
  4.       public static void main(String[] args) {
  5.       HashSet<Integer> hs = new HashSet<Integer>();
  6.       hs.add(14);
  7.       hs.add(7);
  8.       hs.add(21);
  9.       hs.add(28);
  10.       hs.add(35);
  11.       hs.add(42);    
  12.       System.out.println("Initial Size of HashSet: "+hs.size());
  13.       hs.remove(35);
  14.       hs.remove(42);
  15.       System.out.println("Size after removing 2 elements: "+hs.size());
  16.       System.out.println("Final HashSet after removal of 2 elements: ");
  17.       for(int ele: hs){
  18.            System.out.println(ele);
  19.         }
  20.     }
  21. }
import java.util.*;

public class HashSetSize {
      public static void main(String[] args) {
      HashSet<Integer> hs = new HashSet<Integer>();
      hs.add(14);
      hs.add(7);
      hs.add(21);
      hs.add(28);
      hs.add(35);
      hs.add(42);	 
      System.out.println("Initial Size of HashSet: "+hs.size());
      hs.remove(35);
      hs.remove(42);
      System.out.println("Size after removing 2 elements: "+hs.size());
      System.out.println("Final HashSet after removal of 2 elements: ");
      for(int ele: hs){
           System.out.println(ele);
        }
	}
}


Here Size just tells how many elements are present in the HashSet

Don’t get confuse size with capacity in the HashSet, we will talk about capacity separately

Just remember Size() returns number of elements present in HashSet

Remember size() is a method , not a variable in the HashSet class.

About the Author

Karibasappa G C (KB)
Founder of javainsimpleway.com
I love Java and open source technologies and very much passionate about software development.
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