---
title: "Data Types and Operators in Java"
description: Primitive and non-primitive data types, type casting, and operators in Java.
---
## Data Types

### Primitive Types

| Type      | Size    | Example                     |
| --------- | ------- | --------------------------- |
| `int`     | 4 bytes | `int age = 20;`             |
| `float`   | 4 bytes | `float pi = 3.14f;`         |
| `double`  | 8 bytes | `double salary = 35000.50;` |
| `boolean` | 1 bit   | `boolean isStudent = true;` |
| `char`    | 2 bytes | `char grade = 'A';`         |
| `byte`    | 1 byte  | `byte b = 127;`             |
| `short`   | 2 bytes | `short s = 32000;`          |
| `long`    | 8 bytes | `long l = 100000L;`         |

### Non-Primitive Types

Non-primitive types include `String`, `Array`, and user-defined objects. They are reference types that store memory addresses rather than values directly.

## Type Casting

- **Widening (Implicit)** — Smaller type to larger type automatically: `int` to `double`.
- **Narrowing (Explicit)** — Larger type to smaller type requires a cast: `(int) doubleValue`.

## Operators

- **Arithmetic**: `+`, `-`, `*`, `/`, `%`
- **Assignment**: `=`, `+=`, `-=`, `*=`, `/=`
- **Comparison**: `==`, `!=`, `>`, `<`, `>=`, `<=`
- **Logical**: `&&`, `||`, `!`
- **Bitwise**: `&`, `|`, `^`, `~`, `<<`, `>>`

## Example

```java
// DataTypesDemo.java
// Demonstrates primitive and non-primitive data types in Java.

public class DataTypesDemo {
	public static void main(String[] args) {
		// Integer data type
		int age = 20;

		// Double data type (decimal numbers)
		double salary = 35000.50;

		// Character data type
		char grade = 'A';

		// Boolean data type
		boolean isStudent = true;

		// String (non-primitive data type)
		String name = "Alice";

		// Print all variables
		System.out.println("Name: " + name + ", Age: " + age +
			", Salary: " + salary + ", Grade: " + grade +
			", Student: " + isStudent);
	}
}
```

> Full source: [`examples/02-data-types/DataTypesDemo.java`](https://github.com/University-Of-Sri-Jayewardenepura/Java/blob/main/examples/02-data-types/DataTypesDemo.java)