Table of Contents

Arrays

In Java, an array is a container object that holds a fixed number of values of a single type. Think of it as a shelf where you can store and access your books efficiently, rather than scattering them around.

Why Arrays Matter:

Arrays simplify data management by allowing you to:

• Store multiple items in a single, organized structure.
• Perform operations on multiple items simultaneously.
• Search for specific data efficiently.
• Organize information logically for easier access and modification.

Understanding Arrays in Java

Arrays in Java can hold both primitive data types (like int, double, boolean) and objects (like instances of a class). They are indexed starting from 0, making it easy to traverse and access individual elements.

Memory Allocation for Arrays

Java allocates a contiguous memory block for arrays, which enhances the efficiency, especially when accessing elements. Here’s how memory allocation works:

• Primitive Type Arrays: Directly store the actual data. For example, an integer array stores each int value contiguously in memory.
• Object Arrays: Store references (or pointers) to the actual objects. The objects themselves can be scattered across different memory locations.

Example: Arrays

Let's see how arrays work with some simple Java code:

public class ArraysDemo {
    public static void main(String[] args) {
        // Creating an array of integers
        int[] scores = new int[5];

        // Assigning values to the array
        scores[0] = 85;
        scores[1] = 90;
        scores[2] = 95;
        scores[3] = 100;
        scores[4] = 105;

        // Accessing and printing an element from the array
        System.out.println("The score of the third student is: " + scores[2]);
    }
}

In this example, scores is an array that stores the scores of five students. We access the score of the third student (index 2 because arrays start at 0) and print it.

Out-of-Memory Error