Exploring Arrays (Java)

Meet the Author: Marco Ni

Hello readers! This is a simple article introducing one of the simplest and most commonly used data structures… Arrays!

What is an Array?

An array is a collection of elements stored at contiguous memory locations. It allows you to store multiple values of the same type in a single variable, which can be accessed using an index.

Key Concepts

1. Creating an Array
   • Declaration: Define an array and specify its size.
   • Initialization: Assign values to the array elements.
2. Accessing Array Elements
   • Indexing: Access elements using their index. Remember that array indices typically start at 0.
3. Basic Operations
   • Traversal: Loop through the array to access or display all elements.
   • Insertion: Add new elements to the array (for fixed-size arrays, this involves creating a new array and copying elements).
   • Deletion: Remove elements from the array (similar to insertion, it may require creating a new array).

Example in Java

Here’s a simple example of how to work with arrays in Java:

public class ArrayExample {
    public static void main(String[] args) {
        // Declare and initialize an array
        int[] numbers = {1, 2, 3, 4, 5};

        // Accessing and displaying elements
        for (int i = 0; i < numbers.length; i++) {
            System.out.println("Element at index " + i + ": " + numbers[i]);
        }

        // Modifying an element
        numbers[2] = 10; // Changing the value at index 2
        System.out.println("Modified element at index 2: " + numbers[2]);
    }
}

When to Use Arrays

Arrays are useful when:

• You need to store multiple values of the same type.
• You know the number of elements in advance.
• You need fast access to elements using indices.

Limitations

• Fixed Size: Once an array is created, its size cannot be changed.
• Insertion/Deletion Complexity: Adding or removing elements can be cumbersome with fixed-size arrays.

Works Cited

1. GeeksforGeeks. “Arrays in Java.” GeeksforGeeks, 2024, https://www.geeksforgeeks.org/arrays-in-java/.
2. Techopedia. “Array Data Structure.” Techopedia, 2024, https://www.techopedia.com/definition/1241/array-data-structure.