Array in Java

• Arrays are versatile and commonly used in Java for storing and manipulating collections of data.
• In Java, an array is a simple, data structure that stores a static/fixed-size sequential collection of elements of the same data type(homogenous elements).
• Arrays in Java have a fixed size, meaning once they are created, their length cannot be changed. To create a dynamic collection/array in Java that can grow or shrink in size, we can use other data structures such as ArrayList from the Java Collections framework.
• Arrays have a fixed size once they are created, and this size cannot be changed during runtime.
• Arrays are used to store multiple values of the same data type under a single variable name, making it convenient to manage and access elements using indexes.
• Arrays provide a convenient way to work with collections of elements, such as a list of numbers or a group of objects.
• To declare an array of integers, we use as – 

int[] arrayname;      or  int arrayname[];

Now to create an array with 5 elements

arrayname= new int[5];

• To assign static values to the array elements

• We can also initialize an array with constant values at the time of declaration:

int[ ] arrayname= {100, 200, 300, 400, 500};

• The individual elements of the array can be accessed using square brackets [] and an index number/location.
• Array indices start from 0, so arrayname[0] refers to the first element, arrayname[1] refers to the second element, and so on.
• The length of an array can be obtained using the length property.
• We can use a loop to iterate over or display the elements of an array:

The arrayname.length returns the length or size of the array, allowing it to iterate over all the elements using a loop.

• Java also supports multi-dimensional arrays:-

int[ ][ ] arr= new int[3][3];    // 3×3 size two-dimensional array (3 rows, 3 columns).