Java SE 21 OOP and Functional Techniques

4 days left! Save on skills that make you shine with 40% off 3 months of Coursera Plus. Save now

Java SE 21 OOP and Functional Techniques

This course is part of OCP Java SE 21 Certification Preparation Specialization

Instructor: Wiley Skills Network

Included with

Learn more

5 modules

Gain insight into a topic and learn the fundamentals.

Intermediate level

Recommended experience

8 hours to complete

Flexible schedule

Learn at your own pace

5 modules

Gain insight into a topic and learn the fundamentals.

Intermediate level

Recommended experience

8 hours to complete

Flexible schedule

Learn at your own pace

What you'll learn

Design and implement robust Java applications using OOP and functional programming techniques.
Master advanced Java features, including lambdas, collections, and generics.
Utilize modern Java paradigms to create efficient and scalable software solutions.

Details to know

Shareable certificate

Add to your LinkedIn profile

See how employees at top companies are mastering in-demand skills

Learn more about Coursera for Business

logos of Petrobras, TATA, Danone, Capgemini, P&G and L'Oreal

Build your subject-matter expertise

This course is part of the OCP Java SE 21 Certification Preparation Specialization

When you enroll in this course, you'll also be enrolled in this Specialization.

Learn new concepts from industry experts
Gain a foundational understanding of a subject or tool
Develop job-relevant skills with hands-on projects
Earn a shareable career certificate

There are 5 modules in this course

This course will deepen your expertise in Java SE 21, focusing on object-oriented design, advanced class features, and functional programming concepts. You will gain skills in designing robust applications using modern Java paradigms.

Throughout the course, you’ll explore advanced Java topics such as methods, class design, interfaces, enums, records, and inner classes. You'll also dive into functional programming using lambdas and functional interfaces, along with mastering collections and generics for managing and processing data. By the end of this course, you will be equipped to design, implement, and maintain sophisticated Java applications with both object-oriented and functional approaches. What sets this course apart is its combination of theoretical concepts and real-world examples, enabling learners to truly apply what they’ve learned in real projects. The course includes practical examples and review questions that reinforce key Java programming techniques and best practices, ensuring a deep understanding. This course is ideal for intermediate Java developers who wish to deepen their knowledge and expand their expertise in Java SE 21, especially for those interested in enhancing their application design and functional programming skills. This course is part two of a three-course Specialization designed to provide a comprehensive learning pathway in this subject area. While it delivers standalone value and practical skills, learners seeking a more integrated and in-depth progression may benefit from completing the full Specialization. From OCP Oracle Certified Professional Java SE 21 Developer Study Guide Copyright © 2025 by John Wiley & Sons, Inc. All rights, including for text and data mining, AI training, and similar technologies, are reserved. Used by arrangement with John Wiley & Sons, Inc.

This module delves into the structure and functionality of Java methods, including their declarations, signatures, access modifiers, and advanced features like overloading, varargs, and autoboxing. Learners will gain practical skills in organizing code for modularity and reusability, while understanding how variables and access levels interact within methods.

What's included

1 video15 readings1 assignment

1 videoTotal 1 minute

Overview1 minute

15 readingsTotal 75 minutes

Introduction4 minutes
Optional Specifiers6 minutes
Method Name5 minutes
Declaring Local and Instance Variables5 minutes
Instance Variable Modifiers6 minutes
Applying Access Modifiers4 minutes
Protected Access6 minutes
Public Access6 minutes
Class vs. Instance Membership6 minutes
Static Initializers6 minutes
Passing Data among Methods4 minutes
Autoboxing and Unboxing Variables4 minutes
Overloading Methods6 minutes
Varargs5 minutes
Exam Essentials2 minutes

1 assignmentTotal 16 minutes

Mastering Method Definitions and Usage16 minutes

This module delves into advanced Java class design, focusing on inheritance, constructors, method overriding, and object initialization. Learners will explore how to create robust class hierarchies, manage member access, and implement design patterns such as immutability. By the end, you'll be able to structure Java code for greater reusability, maintainability, and exam readiness.

What's included

1 video16 readings1 assignment

1 videoTotal 1 minute

Overview1 minute

16 readingsTotal 88 minutes

Introduction5 minutes
Single vs. Multiple Inheritance3 minutes
Creating Classes5 minutes
Calling the super Reference4 minutes
Declaring Constructors5 minutes
Calling Overloaded Constructors with this()5 minutes
Calling Parent Constructors with super()7 minutes
Initializing Objects6 minutes
Initializing Instances6 minutes
Inheriting Members9 minutes
Redeclaring private Methods6 minutes
Writing final Methods5 minutes
Declaring Abstract Methods6 minutes
Spotting Invalid Declarations5 minutes
Creating Immutable Objects4 minutes
Summary7 minutes

1 assignmentTotal 16 minutes

Class Design Fundamentals16 minutes

This module delves into advanced Java type systems, including interfaces, enums, sealed classes, and records. Learners will explore how to implement and customize these constructs, encapsulate data efficiently, and leverage polymorphism for flexible code design. By the end, you'll be able to apply these features to create robust and maintainable Java applications.

What's included

1 video19 readings1 assignment

1 videoTotal 1 minute

Overview1 minute

19 readingsTotal 106 minutes

Introduction6 minutes
Inheriting an Interface5 minutes
Declaring Concrete Interface Methods12 minutes
Working with Enums5 minutes
Working with Complex Enums5 minutes
Sealing Classes6 minutes
Omitting the permits Clause5 minutes
Encapsulating Data with Records4 minutes
Applying Records3 minutes
Declaring Constructors6 minutes
Using Pattern Matching with Records8 minutes
Customizing Records4 minutes
Declaring an Inner Class6 minutes
Creating a static Nested Class4 minutes
Defining an Anonymous Class4 minutes
Understanding Polymorphism5 minutes
Casting Objects6 minutes
Polymorphism and Method Overriding6 minutes
Summary6 minutes

1 assignmentTotal 16 minutes

Exploring Advanced Java Features16 minutes

This module introduces the fundamentals of lambda expressions, method references, and functional interfaces in Java. Learners will explore how to write and use custom and built-in functional interfaces, leverage concise lambda syntax, and manage variables within lambda bodies. By the end, you'll be able to implement reusable and readable functional code using modern Java features.

What's included

1 video11 readings1 assignment

1 videoTotal 1 minute

Overview1 minute

11 readingsTotal 53 minutes

Introduction5 minutes
Learning Lambda Syntax5 minutes
Coding Functional Interfaces5 minutes
Using Method References5 minutes
Calling Instance Methods on a Parameter4 minutes
Working with Built-in Functional Interfaces6 minutes
Implementing Predicate and BiPredicate6 minutes
Using Convenience Methods on Functional Interfaces6 minutes
Working with Variables in Lambdas5 minutes
Referencing Variables from the Lambda Body4 minutes
Exam Essentials2 minutes

1 assignmentTotal 16 minutes

Lambda and Functional Interface Fundamentals16 minutes

This module delves into the Java Collections Framework, covering essential interfaces and classes such as List, Set, Queue, and Map. Learners will explore how to use generics for type safety, implement sorting and searching with Comparable and Comparator, and understand advanced topics like type erasure and generic methods. By the end, you'll be able to confidently select and manipulate collections for a variety of programming scenarios.

What's included

1 video18 readings1 assignment

1 videoTotal 1 minute

Overview1 minute

18 readingsTotal 97 minutes

Introduction6 minutes
Adding Data6 minutes
Using the List Interface6 minutes
Working with List Methods5 minutes
Using the Set Interface4 minutes
Using the Queue and Deque Interfaces5 minutes
Using the Map Interface5 minutes
Iterating through a Map6 minutes
Sorting Data6 minutes
Comparing Data with a Comparator5 minutes
Sorting and Searching5 minutes
Introducing Sequenced Collections5 minutes
Reviewing Collection Types4 minutes
Working with Generics4 minutes
Understanding Type Erasure6 minutes
Writing Generic Methods10 minutes
Putting It All Together5 minutes
Summary4 minutes

1 assignmentTotal 16 minutes

Java Collections and Generics Fundamentals16 minutes

Earn a career certificate

Add this credential to your LinkedIn profile, resume, or CV. Share it on social media and in your performance review.

Instructor

Wiley Skills Network

John Wiley & Sons

81 Courses4,511 learners

Offered by

John Wiley & Sons

Explore more from Software Development

John Wiley & Sons
Java SE 21 Fundamentals: Syntax, Control Flow, and Core APIs
Course
John Wiley & Sons
Java SE 21: Streams, Modules, Concurrency & I/O
Course

Why people choose Coursera for their career

Felipe M.

Learner since 2018

"To be able to take courses at my own pace and rhythm has been an amazing experience. I can learn whenever it fits my schedule and mood."

Jennifer J.

Learner since 2020

"I directly applied the concepts and skills I learned from my courses to an exciting new project at work."

Larry W.

Learner since 2021

"When I need courses on topics that my university doesn't offer, Coursera is one of the best places to go."

Chaitanya A.

"Learning isn't just about being better at your job: it's so much more than that. Coursera allows me to learn without limits."

Frequently asked questions

To access the course materials, assignments and to earn a Certificate, you will need to purchase the Certificate experience when you enroll in a course. You can try a Free Trial instead, or apply for Financial Aid. The course may offer 'Full Course, No Certificate' instead. This option lets you see all course materials, submit required assessments, and get a final grade. This also means that you will not be able to purchase a Certificate experience.

When you enroll in the course, you get access to all of the courses in the Specialization, and you earn a certificate when you complete the work. Your electronic Certificate will be added to your Accomplishments page - from there, you can print your Certificate or add it to your LinkedIn profile.

Yes. In select learning programs, you can apply for financial aid or a scholarship if you can’t afford the enrollment fee. If fin aid or scholarship is available for your learning program selection, you’ll find a link to apply on the description page.