Java - Singly Linked Lists and the `isEmpty()` method

Hello Dev.to enthusiasts! 🌟

Let's talk data structures. Ever been in a situation where you're not sure if you're working with something, or... well, nothing? That's the quandary our singly linked lists often find themselves in. Enter: the isEmpty() method.

A Quick Refresher: Singly Linked List 📖

First, let's remember what a singly linked list looks like:

class Node {
    int data;
    Node next;

    Node(int data) {
        this.data = data;
        this.next = null;
    }
}

class SinglyLinkedList {
    Node head;
    SinglyLinkedList() {
        this.head = null;
    }
}

Each node in this structure has some data and points to the next node. If there's no next node, it points to null.

The Core of Today's Discussion: isEmpty() 🎯

The isEmpty() method is simple, but vital:

public boolean isEmpty() {
    return head == null;
}

This method checks if the head of our list is pointing to anything. If it isn’t (i.e., it's pointing to null), then our list is, indeed, empty.

Why It Matters 🤷‍♂️

Why is this method so important? Before performing operations on your list, you'd ideally want to know if you're dealing with actual nodes or if you're just about to interact with a void. It's a safety measure that helps prevent issues down the road and, let's face it, those dreaded NullPointerExceptions.

Conclusion 🌅

While the isEmpty() method may seem basic, it's foundational to working with singly linked lists effectively. Understanding it ensures that we're always on the right track, working with data that's present rather than chasing shadows.

In the next article we will look at size() method

Cheers and happy coding! 🚀