TreeSet add() Method in Java

The Java.util.TreeSet.add() method in Java TreeSet is used to add a specific element into a TreeSet. The function adds the element only if the specified element is not already present in the set else the function return False if the element is not present in the TreeSet.


Tree_Set.add(Object element)

Parameters: The parameter element is of the type of TreeSet and it refers to the element to be added to the Set.

Return Value: The function returns True if the element is not present in the set and is new, else it returns False if the element is already present in the set.

Below program illustrates the use of Java.util.TreeSet.add() method:





// Java code to illustrate add()
import java.util.TreeSet;
public class TreeSetDemo {
    public static void main(String args[])
        // Creating an empty TreeSet
        TreeSet<String> tree = new TreeSet<String>();
        // Use add() method to add elements into the Set
        // Displaying the TreeSet
        System.out.println("TreeSet: " + tree);



TreeSet: [4, Geeks, To, TreeSet, Welcome]

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