Java Collection, HashSet Exercises: Get the number of elements in a hash set

Java Collection, HashSet Exercises: Exercise-3 with Solution

Write a Java program to get the number of elements in a hash set.

Sample Solution:

Java Code:

import java.util.*;
import java.util.Iterator;
  public class Exercise3 {
  public static void main(String[] args) {
         // Create a empty hash set
     HashSet<String> h_set = new HashSet<String>();
   // use add() method to add values in the hash set
    System.out.println("Original Hash Set: " + h_set);
    System.out.println("Size of the Hash Set: " + h_set.size());

Sample Output:

Original Hash Set: [Red, White, Pink, Yellow, Black, Green]            
Size of the Hash Set: 6 

Pictorial Presentation:

Java Collection, ArrayList Exercises: Get the number of elements in a hash set


Flowchart: Get the number of elements in a hash set.

Java Code Editor:

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Previous: Iterate through all elements in a hash list.
Next: Empty an hash set.

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Java: Tips of the Day


Converts to enum to Map where key is the name and value is Enum itself.

public static <E extends Enum<E>> Map<String, E> getEnumMap(final Class<E> enumClass) {
    return Arrays.stream(enumClass.getEnumConstants())
            .collect(Collectors.toMap(Enum::name, Function.identity()));

Ref: https://bit.ly/3xXcFZt