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Introduction to Arrays in Java
Point Heading: What is an Array?
An array is a data structure that stores a fixed-size sequential collection of elements of the same type. It is used to store data of the same type in a contiguous memory location.
Point Heading: Declaring an Array
In Java, arrays are declared using the following syntax: dataType[] arrayName; or dataType arrayName[];.
Point Heading: Instantiating an Array
To instantiate an array, use the new keyword followed by the data type and the size of the array: arrayName = new dataType[size];.
Point Heading: Initializing an Array
Arrays can be initialized at the time of declaration using curly braces: dataType[] arrayName = {value1, value2, ...};.
Point Heading: Accessing Array Elements
Array elements are accessed using their index, starting from 0: arrayName[index];.
Point Heading: Array Length
The length of an array can be obtained using the length property: arrayName.length;.
Step 1: Declare an array.
Step 2: Instantiate the array.
Step 3: Initialize the array with values.
Step 4: Access elements using indices.
Step 5: Use the length property to find the size.
public class ArrayExample {
public static void main(String[] args) {
// Step 1: Declare an array
int[] numbers;
// Step 2: Instantiate the array
numbers = new int[5];
// Step 3: Initialize the array
numbers[0] = 10;
numbers[1] = 20;
numbers[2] = 30;
numbers[3] = 40;
numbers[4] = 50;
// Step 4: Access array elements
System.out.println("First Element: " + numbers[0]);
// Step 5: Get the array length
System.out.println("Array Length: " + numbers.length);
}
}
Point Heading: Advantages of Arrays
Arrays provide a way to store multiple items of the same type together, allowing for efficient data management and manipulation.
Point Heading: Limitations of Arrays
The size of an array is fixed upon creation, which can lead to inefficiencies if the number of elements varies significantly.
Console Output:
First Element: 10
Array Length: 5
