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Java LinkedList public Object peek() method with Example

Java LinkedList public Object peek() method: Here, we are going to learn about the public Object peek() method of LinkedList class with its syntax and example.
Submitted by Preeti Jain, on June 22, 2019

LinkedList public Object peek() method

• This method is available in package java.util.LinkedList.peek().
• This method is used to retrieve the head element of the linked list without removing the head element.
• If the list is empty then it will return null.

Syntax:

    public Object peek(){
    }

Parameter(s):

In this method, we don’t pass any object as a parameter in the method but it returns the first object from the linked list.

Return value:

The return type of this method is not void that means this method returns head object or element (i.e. It returns the only first element in the list). If the list is empty then it will not give any exception.

Java program to demonstrate example of LinkedList peek() method

import java.util.LinkedList;

public class LinkList {
    public static void main(String[] args) {
        LinkedList list = new LinkedList();
        // use add() method to add elements in the list 
        list.add(10);
        list.add(20);
        list.add(30);
        list.add(40);
        list.add(50);

        //  Current list Output
        System.out.println("The Current list is:" + list);

        //  Using peek() method it will retrieve first element 
        // without removing the element from the list  
        System.out.println("The First Element In The List is:" + list.peekFirst());
    }
}

Output

D:\Programs>javac LinkList.java

D:\Programs>java LinkList
The Current list is:[10, 20, 30, 40, 50]
The First Element In The List is:10