Summary

Congrats!

Congratulations on completing the Java OOP course! You've done a fantastic job making it this far! This course might have been short, but it was challenging. Object-oriented programming concepts are a crucial part of any programming language. The same programming concepts can be applied in other programming languages as well, as they remain consistent across languages, with only syntax differences.

Let's quickly recap what we've learned in this course:

OOP

Object-Oriented Programming (OOP) is a programming paradigm that focuses on organizing code around objects, which are instances of classes. OOP promotes concepts like encapsulation, inheritance, polymorphism, and abstraction to create modular, reusable, and maintainable code.

OOP concepts:

• Inheritance

SubClass

Class


              123
            
public class SubClass extends Class {
  // some code
}

• Polymorphism

SubClass

Class


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public class SubClass extends Class {
    @Override
    public void method() {
        // some implementation
    }
    
    public void method(String parameter) {
        // other implementation
    }
}

• Encapsulation

Example


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public class Example {
    public int publicField;
    protected int protectedField;
    int defaultField;
    private int privateField;
}

• Abstraction

AbstractClass

Interface


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public abstract class AbstractClass {
    // some code with abstract methods
}

These principles collectively enhance code organization, reusability, and maintainability, making OOP a powerful paradigm for software development. Each principle addresses specific aspects of designing and structuring classes and objects to create effective and efficient code.

Interface

Java interfaces are a fundamental concept in object-oriented programming that allows developers to define a contract for classes to adhere to. An interface serves as a blueprint for methods that must be implemented by classes that implement the interface. This promotes code reusability, maintainability, and multiple inheritance, as a class can implement multiple interfaces.

Abstract class vs Interface

Abstract class and interface serve very similar functions.

An abstract class is a class that provides some functionality and enforces certain rules but leaves some parts for its subclasses to complete;
An interface, on the other hand, is like a checklist that a class needs to fulfill, specifying what methods it must have, without providing any actual code. The illustration below highlights their main features:

And the most important conclusion - you're doing a fantastic job. I believe that you will succeed and get one step closer to mastering Java. This course might have been short but challenging. If you manage to grasp the concepts covered in this course, a bright future awaits you!

Everything was clear?

Thanks for your feedback!

Section 3. Chapter 6