What is Array in Java

• Array is a collection of similar data types stored in under a common name.

*Its stored homogeneous data into array.

*It helps you store multiple values in a single variable instead of declaring separate variables for each value.

*Array value store in heap memory

*Here JVM will manage to create the memory for the Array object.

*It is a index based.

*The starting index will be 0.

*Each element is accessed by its index, starting from 0.

*In Java, the size of an array cannot change once it is created.

*You can modify the elements inside it, but not the length.

*No import is needed for arrays in Java.Arrays are built into the Java language itself — they are part of the core language.

If you want to use these methods Arrays.sort(), Arrays.toString() should import this package **import java.util.Arrays;*.

• — but it can store both primitive and non-primitive values inside it.

WHY WE USE ARRAY:

*We use arrays in Java because they let us store and manage multiple values efficiently using a single variable name — instead of creating many separate variables.

*Store multiple values together
Instead of many variables, one array holds many items.

*Easy looping
We can access all elements using a loop.

*Fast access by index
Access any element directly using its index (like marks[2]).

*Memory efficiency
Elements are stored contiguously in memory.

ARRAY SYNTAX:

Declaration and then creation
dataType[] arrayName = new dataType[size];

Example:

int[] numbers = {10, 20, 30, 40, 50};

Declare the size of the Array:
int[] numbers; // Declaration
numbers = new int[3]; // Creation
numbers[0] = 10;
numbers[1] = 20;
numbers[2] = 30;

Getting array size:
System.out.println(numbers.length); // prints number of elements

Advantages of arrays:

*Stores multiple values in a single variable.

*Easy access using index.

*Useful for calculations and data analysis.

*Memory efficiency.

Simplifies code.
*
Disadvantages of arrays:**

*Fixed size.

*Once an array is created, its size cannot be changed.

*Can store only one data type.

*3️⃣ No built-in methods for easy operations

Arrays do not have built-in methods for:

Adding or removing elements

Searching specific items

Checking if an element exists.

*Wastage or shortage of memory

Because size is fixed:

If you allocate too large, memory is wasted.

If you allocate too small, it can’t hold all data.