ARRAY IN JAVA

What is array in java?

• In Java, an array is a fundamental data structure that serves as a container object holding a fixed number of values of a single type. These values are stored in contiguous memory locations and are accessed using a zero-based index.

Why array using in java?

• Arrays are used in Java for several key reasons, primarily to efficiently manage and store collections of data of the same type:

Key features of Arrays:

Contiguous Memory Allocation (for Primitives):

• Java array elements are stored in continuous memory locations, which means that the elements are placed next to each other in memory.

Zero-based Indexing:

• The first element of the array is at index 0.

Fixed Length:

• Once an array is created, its size is fixed and cannot be changed.

Can Store Primitives & Objects:

• Java arrays can hold both primitive types (like int, char, boolean, etc.) and objects (like String, Integer, etc.)

Basics of Arrays in Java

• There are some basic operations we can start with as mentioned below:

1. Array Declaration

• To declare an array in Java, use the following syntax:

type[] arrayName;

type: The data type of the array elements (e.g., int, String).
Arrayname: The name of the array.
Note: The array is not yet initialized.

2. Create an Array

• To create an array, you need to allocate memory for it using the new keyword:

// Creating an array of 5 integers
int[] numbers = new int[5]; 

This statement initializes the numbers array to hold 5 integers. The default value for each element is 0.

3. Access an Element of an Array

• We can access array elements using their index, which starts from 0:

// Setting the first element of the array
numbers[0] = 10; 

// Accessing the first element
int firstElement = numbers[0]; 

The first line sets the value of the first element to 10. The second line retrieves the value of the first element.

4. Change an Array Element
* To change an element, assign a new value to a specific index:

// Changing the first element to 20
numbers[0] = 20; 

5. Array Length

• We can get the length of an array using the length property:

// Getting the length of the array
int length = numbers.length; 

sample program for array string

public class Example {

    public static void main(String[] args) {
        String[] myArray = {"foo", "bar", "baz"};

        // retrieval
        System.out.println(myArray[0]);
        System.out.println(myArray[1]);
        System.out.println(myArray[2]);
    }
}

REFFERED LINKS
1.https://www.geeksforgeeks.org/java/arrays-in-java/
2.https://opensource.com/article/22/11/arrays-java