1. Introduction

In this tutorial, we aim to understand the different data types in Java and learn how to use them effectively in our programs. Data types are an essential concept in any programming language, and understanding how they work in Java will help you write efficient and error-free code.

By the end of this tutorial, you will:
- Understand what data types are and why they are important
- Learn about the different data types in Java
- Understand how much memory each data type consumes
- Learn about the operations that can be performed with each data type

Prerequisites: Basic understanding of programming concepts and familiarity with Java syntax.

2. Step-by-Step Guide

Java is a statically-typed language, which means you need to declare the type of data a variable can store. Java has two categories of data types: primitive types and reference types.

Primitive Data Types

These are the most basic data types in Java. They include byte, short, int, long, float, double, boolean, and char.

• byte: This is an 8-bit signed two's complement integer. The value can range from -128 to 127 (inclusive).
• short: A short is a 16-bit signed two's complement integer, with values ranging from -32,768 to 32,767.
• int: This is a 32-bit signed two's complement integer, with values ranging from -2^31 to 2^31-1.
• long: A long is a 64-bit two's complement integer, with a value ranging from -2^63 to 2^63-1.
• float: This is a single-precision 32-bit IEEE 754 floating point.
• double: This is a double-precision 64-bit IEEE 754 floating point.
• boolean: A boolean data type only has two possible values: true and false.
• char: This is a single 16-bit Unicode character, with values ranging from 0 to 65,535.

Reference Data Types

Reference data types are used to store the reference of an object. These include classes, interfaces, arrays, etc.

3. Code Examples

// declaring an integer
int myAge = 25;
System.out.println(myAge); // output: 25

// declaring a float
float pi = 3.14f;
System.out.println(pi); // output: 3.14

// declaring a boolean
boolean isJavaFun = true;
System.out.println(isJavaFun); // output: true

4. Summary

In this tutorial, we covered the different data types in Java, including both primitive and reference types. Understanding these data types and how they work is a crucial part of Java programming.

For further reading, you can explore the official Java documentation or other online resources.

5. Practice Exercises

1. Declare a double variable with the value 10.99 and print it.
2. Declare a char variable with the value 'A' and print it.
3. Declare a boolean variable with the value false and print it.

Solutions:

// Exercise 1
double price = 10.99;
System.out.println(price); // output: 10.99

// Exercise 2
char letter = 'A';
System.out.println(letter); // output: A

// Exercise 3
boolean isCompleted = false;
System.out.println(isCompleted); // output: false