Java Essentials Track - Online Learning with Certificate

Java Essentials

Beginner

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Embark on a comprehensive journey into the realm of Java programming. Whether you're just starting or have some coding experience, this track will equ…

270

Chapters

Learning hours

459

Assignments

AI Assistant

Shareable Certificate

Outcomes

Track content

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What you will learn

Writing your first Java program

Implementing control structures

Creating and using Java classes

Understanding Java's basic syntax

Mastering loops for efficient iteration

Applying OOP principles in Java

Using primitive data types in Java

Working with arrays and strings

Exploring Java data structures

Learning track content

Discover the unique features of Java and understand why it's a recommended programming language to learn. Write your first Java code and explore how to print text to the console.

Backend Development

Role of Java in the Backend

Learn the basics of programming, dive into primitive data types, and explore operations with them. Write code that performs mathematical tasks and evaluates conditions for seamless execution.

Primitive Data Types

Challenge: Primitive Types

Mathematical Operations in Java

Mathematical Operations on char

If-Else Statement

Switch-Case Statement

New Task Structure

Challenge: Weekday Switch

Explore various loops such as for, while, and do-while, which are essential in any programming language. Loops enable efficient iteration over large datasets, saving significant time. Apply them extensively in tasks like sorting, working with arrays, collections, and more.

Introduction to Loops

While-Loop

Do-While Loop

Challenge: Building a Server Retry Mechanism

For-Loop

Increment and Decrement

Infinite Loop

Challenge: Filtering Numbers in a Loop

Learn how to effectively use arrays in Java programming by discovering how to group data into arrays and exploring common methods and properties for working with them. Techniques for manipulating and optimizing arrays in real-world applications will also be examined.

What is Array?

Using Loops with Arrays

Index Out Of Bounds

Two-Dimentional Array

Iteration In Two-Dimensional Array

For-Each Loop

Learn about String, a crucial data type in Java, and discover its many built-in methods and operations. Explore String and StringBuilder, understanding their basic methods and how to use strings effectively in Java.

What Is String?

Basic Methods In String

Practical Applications of String Methods

Challenge: Filter Failure Messages

NullPointerException

StringBuilder

String Pool, Method Equals()

Summary

Explore Java's built-in primitive data types, their properties, and how to use them effectively.

Overview of Primitive Types

Numeric Literals and Type Suffixes

Challenge: Integer Operations

Challenge: Floating Point Precision

Delve into Java's reference types, focusing on Strings and arrays, and how they differ from primitives.

Understanding Reference Types

Working with Strings

Challenge: String Manipulation

Challenge: Array Basics

Challenge: Null Reference Handling

Learn about type casting, automatic conversions, and the use of wrapper classes for primitives.

Type Casting and Promotion

Wrapper Classes and Autoboxing

Challenge: Safe Type Conversion

Challenge: Using Wrapper Classes

Challenge: Autoboxing in Collections

Introduce the concept of loops, their necessity, and the basic structure of for, while, and do-while loops in Java. This section lays the foundation for understanding how repetition works in programming.

What Are Loops?

for Loop in Java

while Loop in Java

Challenge: Even Number Collector

Dive deeper into different loop types, including do-while loops and nested loops, and learn how to control loop execution with break and continue.

do-while Loop in Java

Nested Loops

Loop Control

Challenge: Simulating Network Retries

Apply loop concepts to solve practical problems, including working with arrays and combining loops with conditionals.

Loops and Arrays

Combining Loops and Conditionals

Challenge: Array Sum Calculator

Throughout the following lessons, you will become acquainted with the inner workings of Java and discover optimized methods to work with the language. This will involve exploring Java's operations at the computer level and adopting best practices for utilizing familiar concepts efficiently.

How Does the Compiler Works?

Data Transfer in Java

Final Keyword

Importing Libraries

Using Libraries In Our Code

Ternary Operator

Enhanced Switch Statement

You have already encountered methods, and now you will finally understand what they actually are, how to create your own methods, and how to work with them. You will learn to return the desired values from methods and significantly improve the quality and logic of your code.

What is a Method?

Creating Our Own Methods

Challenge: Names Starting with Letter B

Challenge: Find Maximum and Minimum in Array

Get ready to dive into the world of String and discover more about its inner workings and methods. We'll explore the fascinating features that String offers, including the ability to customize the "toString" method, split strings into substrings, and utilize indexes for efficient data retrieval. Let's embark on this exciting journey to expand our knowledge of String manipulation!

Deeper into String

Method split()

Challenge: Uppercase Even Words

indexOf() Method

Challenge: Finding the Longest Word

trim() Method

Challenge: Email Validation

In this section, you will learn how to create your own classes and their objects. You will be able to use methods of one class within another and establish relationships between them. Get ready to discover many interesting concepts and delve deeper into OOP programming!

What is Class?

Main Class and Method

Access Modifiers

Class Creation

Challenge: Get Information About the Object

Constructor

Challenge: Team Constructor

Method toString()

Challenge: Parrot Information Display

In this section, we will continue our study of classes. We will explore more advanced usage of class objects and learn more about access modifiers and how to use them effectively. We will also delve into getters and setters, as they are considered best practices in programming.

Complex Classes Usage

Challenge: Pet and Owner Relationship

Private Modifier

Challenge: Animal Information Display

Getter and Setter

Challenge: Updating User Information

Summary

Explore the foundational principles that guide effective and maintainable Java code, including SOLID, DRY, KISS, and YAGNI.

Understanding SOLID Principles

Applying DRY

KISS in Practice

YAGNI

Master the essential clean code practices that lead to readable, maintainable, and high-quality Java code.

Readability in Java Code

The Refactoring Mindset

Naming Conventions and Best Practices

Maintainability and Technical Debt

Delve into core architectural and design principles that underpin robust Java applications.

Layered Architecture in Java

Separation of Concerns

Modular Design for Scalable Systems

Installing Java

Installing IntelliJ IDEA on MacOS

Installing IntelliJ IDEA on Windows

Code Editor Main Features

Debugger

Packages

How to do Tasks?

Finally, we can start learning Object-Oriented Programming (OOP) in Java. It will be challenging, but I'm confident that you'll succeed! In this section, we'll cover all the principles of OOP, explain why OOP is important. You'll learn how to inherit classes, overload and override methods, encapsulate data from other classes, and work with abstraction. Moreover, you'll reinforce all these theoretical concepts with practical exercises, working on assignments in your IDE. You'll gain a wealth of knowledge, both practical and theoretical, so let's get started!

What is OOP?

OOP Principles Inheritance

Challenge: Inheritance

OOP Principles Polymorphism

Challenge: Polymorphism

OOP Principles Encapsulation

OOP Principles Abstraction

Challenge: Abstraction

In the previous section, we concluded that all Object-Oriented Programming is mainly built on abstraction. However, an abstract class has one significant limitation – you can inherit from only one abstract class. But what if we need more? Interfaces come to the rescue. In this section, you will learn what an interface is, why it's necessary, how to use it correctly, and you will continue practicing Object-Oriented Programming. Let's turn you into a professional!

What is Interface?

Challenge: Interface

Abstract Class vs Interface

Default Methods

Static Methods

Summary

Discover the concept of lists and explore the most commonly used types in Java. Learn how to create, modify, and manage lists efficiently. Understand their internal structure and discover when to use ArrayList vs. LinkedList based on performance. Implement your own singly linked list and reinforce key concepts through practical coding challenges.

Introduction to Data Structures

List and ArrayList in Java

Challenge: Library Management System

CRUD Operations in Java

LinkedList in Java

Implementing LinkedList in Java

Challenge: Implementing size and delete Methods in LinkedList

Quiz: Fundamental Data Structures

Learn about data structures that are not as commonly used but are still valuable. Data structures like Set, Stack, Queue, and Deque will help you better understand how Java works and their various applications in databases.

Queue Data Structure in Java

Deque Data Structure in Java

Challenge: Implementing a TaskManager Service

Stack Data Structure in Java

Challenge: Implementing BrowserHistory

Quiz: Advanced Data Structures

Learn about key-value pair-based data retrieval, enabling the creation of structures similar to databases. Discovery of concepts like hashcode and exploration of data structures such as HashMap and HashSet are also included.

What is Map?

Working with HashMap in Java

HashMap Practice in Java

Map with Other Data Structures

Quiz: Mastering Map

Learn to use enum for defining a fixed set of constants and explore the Stream API to process, filter, and transform data efficiently.

Working with Enum in Java

Challenge: Implementing Character Classes

Stream API in Java

Method Reference in Java

Practicing with Stream API

Quiz: Enum and Stream API

Let's talk about types of testing and which testing methods developers use. You will learn about the stages an application goes through before being delivered to the client and the specific tests you will need to write.

What is Testing, and Why do We Need It

In this section, we're going to dive into unit testing — you'll get the rundown on its structure in Java and the ins and outs of crafting them the right way. Setting up your IDE, importing necessary libraries, and lots of hands-on practice.

Set-Up

Test-Driven Development

Creating Unit Tests

@BeforeEach

How to Test `void` Methods

Assertions

Assertions Practice

Section 2 Summary

In this section, we will enhance our coding skills by dealing with errors that can also be caught in unit tests. When testing an application, you may come across various errors, and sometimes they should be turned into exceptions. I will explain how to catch exceptions in your code, test them, and handle them properly.

Throwing Exceptions

Try-catch structure

Handling Multiple Exceptions

Handling Exceptions Practice

Creating Exceptions

Testing Exceptions

Testing Exceptions Practice

This section will delve into the foundational concepts of multithreading in Java, focusing on the creation and management of threads, and the use of synchronization techniques to avoid conflicts. You’ll also learn how to utilize essential keywords and methods to ensure the accurate and reliable execution of multithreaded programs, providing a solid understanding of how to handle concurrency effectively in your applications.

What is Multithreading

Difference Between Multithreading and Single-Threading

Threads in Java

Thread Synchronization

Performance and Challenges

Atomicity

Multithreading Task

This section explores synchronized collections in Java, explaining their purpose and the common concurrency issues they are designed to solve. You’ll gain insights into how these collections work, why they are essential in multithreaded environments, and how they help ensure safe and consistent data manipulation when multiple threads access shared resources.

Collections with Multithreading Support

Parallel Stream API

BlockingQueue and its Implementations

Сhallenge: BlockingQueue

ConcurrentMap and its Implementations

Challenge: ConcurrentMap

CopyOnWrite Collection

Examples of Using Collections Methods

This section covers high-level synchronization mechanisms in Java, such as the use of Lock and Condition, semaphores, barriers, atomic variables, and thread pooling with Executors. Each topic is paired with practical exercises designed to reinforce your understanding and help you apply the theoretical knowledge to real-world scenarios.

Lock and Condition

Challenge: Lock и Condition

Semaphore and Barrier

Challenge: Semaphore

Atomic Variables

Executors and Thread Pool

Challenge: Executors

This section explores fundamental multithreaded programming patterns and practices such as Producer-Consumer, Fork/Join, ThreadLocal, and asynchronous programming with CompletableFuture. You'll work through examples and see the practical outcomes of these approaches, gaining hands-on experience that will enable you to apply these techniques effectively in real-world applications.

Producer-Consumer

ForkJoinPool

Challenge: ForkJoinPool

ThreadLocal

Basics of Asynchronous Programming

CompletableFuture

Challenge: CompletableFuture

Summary Multithreading

Learn the fundamentals of lambda expressions, their syntax, and how they fit into Java's type system.

Introduction to Lambda Expressions

Functional Interfaces Explained

Lambda Syntax Variations

Scope and Variable Capture

Common Built-in Functional Interfaces

Challenge: Implement a Custom Predicate

Dive deeper into lambda expressions with method references, composition, and practical applications in collections.

Method References

Lambdas with Collections

Composing Lambdas

Lambdas and Exception Handling

Lambdas in Stream API

Challenge: Stream Data Processing

Learn how to write clean, efficient, and maintainable code with lambda expressions in real-world scenarios.

Readability and Maintainability

Performance Considerations

Lambdas in Event-Driven Programming

Testing Lambda Expressions

Lambdas in Real-World Applications

Challenge: Event Handler with Lambda

Discover how Stream API revolutionizes data processing in Java with its expressive and functional approach. Explore its architecture, principles, and key functional features to write concise and efficient code.

Architecture

Principles

What Is a Functional Interface?

Predicate: Data Filtering

Challenge: Filtering Corporate Email Addresses

Function: Data Transformation

Challenge: Income Tax Calculation

Comparable: Natural Ordering of Data

Comparator: Custom Comparison of Data

Challenge: Sorting Employees

Consumer: Processing Data

Supplier: Data Generation

Bi-versions of Functional Interfaces

Challenge: Filtering Users by Two Criteria

BinaryOperator: Combining Two Values

Learn about various intermediate operations available in the Stream API that allow you to manipulate and process data in a functional style. These operations, such as filtering, transforming, and sorting, enable you to efficiently work with collections and perform tasks like removing duplicates, limiting results, or handling nested structures. Each operation can be combined to create powerful data pipelines, making your code more concise and readable.

Transforming Elements with the map() Method

Filtering Elements with the filter() Method

Challenge: Factory Product Filtering

Working with Nested Structures with the flatMap() Method

Arranging Items in Order with the sorted() Method

Challenge: Selecting the Best Cars on the Production Line

Eliminating Duplicates with the distinct() Method

Challenge: Factory Quality Control

Restricting and Skipping Elements with the limit() and skip() Methods

Challenge: Finding the Top 3 Hardest-Working Employees

Intermediate Processing with the peek() Method

Learn about various terminal operations available in the Stream API that allow you to process and retrieve data efficiently. These operations, such as collecting, reducing, and counting, enable you to aggregate results, find specific elements, or perform side effects like printing or writing to a file. Understanding these operations helps you efficiently handle data processing tasks while keeping your code concise and expressive.

collect() Gathering Stream Elements into a Collection

Challenge: Build a Custom Collector for Category Counting

Collectors Utility Class for Stream API

Processing Elements with the forEach() Method

Handling Values with the Optional Class

Aggregating Elements with the reduce() Method

Challenge: Calculating Total Cost with Discounts and Tax

Calculating Stream Statistics with count(), max(), and min()

Retrieving Stream Summary Metrics with summaryStatistics() Method

Retrieving Elements from a Stream with findFirst() and findAny()

Challenge: Selecting Random Products Within a Category

Checking Stream Elements Against a Condition with allMatch()

Challenge: Ensuring Fast Delivery for Expensive Products

Discover how to apply Stream API in real-world scenarios, improving code readability and efficiency. Learn how to refactor existing code, analyze performance trade-offs, and handle exceptions properly. Will help you write cleaner and more maintainable Java code using Stream API.

Real-World Examples of Using Stream API

Performance in Stream API

Exception Handling in Stream API

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