Java Data Types

Data types in Java define the type of data a variable can store. Java is a strongly typed language, which means you must specify the data type when declaring a variable.

Types of Data Types

Java has two main types of data types:

Primitive Data Types
Non-Primitive Data Types

Primitive Data Types

Primitive data types are the basic types built into Java.

int → stores whole numbers
double → stores decimal numbers
char → stores a single character
boolean → stores true or false

Example

public class Main {
  public static void main(String[] args) {
int age = 25;
double price = 10.5;
char grade = 'A';
boolean isActive = true;

System.out.println(age);
System.out.println(price);
System.out.println(grade);
System.out.println(isActive);
  }
}

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Non-Primitive Data Types

Non-primitive data types are more complex and are used to store collections or objects.

String → stores text
Array → stores multiple values
Class → used to create objects

Example

public class Main {
  public static void main(String[] args) {
String name = "Ali";

int[] numbers = {1, 2, 3};

System.out.println(name);
System.out.println(numbers[0]);
  }
}

Try this code

Difference Between Primitive and Non-Primitive

Primitive types store simple values
Non-primitive types store references to objects
Primitive types are faster
Non-primitive types have methods and properties

Important Note

Each data type uses a different amount of memory. Choosing the correct data type helps improve performance.

Why Data Types are Important

They define what kind of data can be stored
They help prevent errors
They improve program performance
They make code more organized