Java Collection, TreeSet Exercises: Get the number of elements in a tree set

Java Collection, TreeSet Exercises: Exercise-7 with Solution

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

Sample Solution:

Java Code:

import java.util.TreeSet;
import java.util.Iterator;

  public class Exercise7 {
  public static void main(String[] args) {
    // create an empty tree set
     TreeSet<String> t_set = new TreeSet<String>();
   // use add() method to add values in the tree set
     System.out.println("Original tree set: " + t_set);
    System.out.println("Size of the tree set: " + t_set.size());

Sample Output:

Original tree set: [Black, Green, Pink, Red, orange]                   
Size of the tree set: 5 


Flowchart: Get the number of elements in a tree set

Java Code Editor:

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Previous: Clone a tree set list to another tree 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