Home » Java programming language

Java TreeSet iterator() Method with Example

TreeSet Class iterator() method: Here, we are going to learn about the iterator() method of TreeSet Class with its syntax and example.
Submitted by Preeti Jain, on February 20, 2020

TreeSet Class iterator() method

• iterator() method is available in java.util package.
• iterator() method is used to iterate the elements of this TreeSet is ascending or increasing order.
• iterator() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
• iterator() method does not throw an exception at the time of iterating elements by using iterator().

Syntax:

    public Iterator iterator();

Parameter(s):

• It does not accept any parameter.

Return value:

The return type of the method is Iterator, it returns TreeSet element in ascending order.

Example:

// Java program to demonstrate the example 
// of Iterator iterator() method of TreeSet 

import java.util.*;

public class IteratorOfTreeSet {
    public static void main(String[] args) {
        // Instantiates a TreeSet object
        TreeSet < String > tree_set = new TreeSet < String > ();

        // By using add() method is to add
        // the given object of this TreeSet 
        tree_set.add("C");
        tree_set.add("C++");
        tree_set.add("JAVA");
        tree_set.add("PHP");
        tree_set.add("SFDC");

        // Display TreeSet
        System.out.println("TreeSet: " + tree_set);

        // By using iterator() method is to
        // iterate the TreeSet elements in an
        // increasing order
        System.out.println("tree_set.iterator(): ");
        for (Iterator itr = tree_set.iterator(); itr.hasNext();)
            System.out.println(itr.next());
    }
}

Output

TreeSet: [C, C++, JAVA, PHP, SFDC]
tree_set.iterator(): 
C
C++
JAVA
PHP
SFDC