Introduction

This article serves as a summary aimed at reinforcing the content of the Object-Oriented Programming course in the IT Management - FAPAM program, 2nd semester.

Lectures taught by professor Daniel Oliveira Capanema.

The OOP concepts will be discussed using the programming language Java.

This article assumes that you already have a basic understanding of programming logic.

What is OOP?

OOP (Object-Oriented Programming) is a programming paradigm that uses objects to represent real-world entities. An "object" refers to anything that has characteristics and behaviors.

For example, a car can be represented as an object with attributes like color, model, and brand, and methods like accelerate and brake.

In programming, particularly in Java, an object is an instance of a class. A class is a blueprint that defines the attributes and behaviors of an object.

We will connect these concepts to Java as we go further.

What is Java?

Java is a high-level, object-oriented, and cross-platform programming language. It was created by Sun Microsystems in 1995 and is one of the most popular programming languages in the world.

Java is both a compiled and interpreted language. This means the source code is compiled into an intermediate code called bytecode. This bytecode is interpreted by the Java Virtual Machine (JVM), which is responsible for executing the code on any operating system.

The main advantage of Java is portability. Since the JVM interprets the bytecode, the same code can run on any operating system with a JVM. This is known as "write once, run anywhere."

Where is Java used?

Java is a highly versatile language and is used in various fields such as web development, desktop applications, mobile apps, gaming, embedded systems, and more.

Additionally, Java was the official language for developing Android apps until Kotlin—a "better Java"—emerged. However, Kotlin is not the focus of this article.

Check out this blog post by Oracle showcasing the 25 greatest apps ever written in Java.

Installing Java

This article won't provide a step-by-step guide for installing Java on every platform since the process may change over time. Instead, I'll point you to official Java development resources. Exercise your research skills! ;)

To start programming in Java, you need to install the JDK (Java Development Kit). The JDK is a set of tools that allows you to develop Java applications.

Visit the Oracle website and download the latest version of the JDK. Follow the installation instructions for your operating system.

After installation, you can verify that Java is installed correctly by opening the terminal and typing:

java -version