Java Masterclass 2025: 130+ Hours of Expert Lessons

Install and configure JDK 17 and IntelliJ IDEA for Java development, explore editions, and set up cross-platform workflows on Windows, macOS, and Linux.

Install Java 17 (LTS) on Windows 10 or 11 by downloading the x64 JDK from java.sun.com and running the installer, noting 32-bit Windows 10 may need an older JDK.

Install OpenJDK 17 on Ubuntu 22.04 using the terminal, run apt update, install openjdk-17-jdk, verify with java -version, and prepare for IntelliJ setup.

Start by printing 'Hello World' in JShell, then modify the statement to say 'Hello Tim', and learn to spot common errors like missing parentheses or quotes while practicing.

Understand byte, short, and long data types in Java, their ranges and widths, plus using wrapper classes and the L suffix to print values and explore overflow.

Explore Java floating point numbers, compare float and double, learn their ranges and precision, understand decimal literals, suffixes F and D, and casting implications.

Explain how int, float, and double handle division and precision, showing truncation for integers and 2.5 for floats and doubles, with doubles offering greater accuracy.

Explore Java's char and boolean primitives, learn single-character storage with quotes, unicode, or decimal codes, and use booleans with is-prefixed names for true/false conditions.

Master abbreviating operators in Java, including postfix ++/-- and compound assignments like += and -=, with int and double examples to illustrate data-type effects.

Switch from jshell to an integrated development environment to boost productivity. Install and configure IntelliJ IDEA, and learn code completion, debugging, and version control.

Discover how an integrated development environment like IntelliJ IDEA simplifies writing, compiling, and running code, with built in error warnings and streamlined setup across Windows, Mac OS, and Linux.

Install and set up IntelliJ IDEA on macOS, selecting the Apple Silicon or Intel version, download from JetBrains, and complete initial configuration to write, run, and debug Java programs.

Install and start IntelliJ IDEA on Ubuntu Linux using snap or tarball, then configure the ide to write and run programs.

Configure IntelliJ IDEA for Windows by linking the JDK, selecting Java as the project type, and enabling auto-imports, unambiguous imports on the fly, and optimize imports on the fly.

Configure IntelliJ IDEA for Mac by linking Oracle's JDK 25 to enable Java code. Set the IDE build system and enable auto-import plus show line numbers for easier learning.

Explore how IntelliJ displays and formats Java code, learn the roles of classes and the main method, and distinguish println from print for proper output.

Master conditional logic in Java by learning the if-then statement, the assignment operator and equality operator, boolean evaluation, and the importance of code blocks for clear program flow.

Explore advanced conditional logic in Java with equality and comparisons like greater than, greater than or equal to, less than, less than or equal to, plus the logical and operator.

Explore Java's logical and operator and logical or operator within conditional statements, and learn how operator precedence and parentheses clarify boolean expressions in code.

Demonstrates the difference between the assignment and equals operators in Java, fixes common int and boolean comparisons in IntelliJ, and introduces the not operator for concise boolean expressions.

Explore Java operator precedence through a hands-on challenge, using doubles, modulus, and parentheses to control evaluation order, and learn how precedence affects expressions and outcomes.

Explore Java keywords and expressions, mastering reserved and contextual keywords, identifiers, and how expressions form statements and code blocks in practical IntelliJ examples.

Master how to write valid Java statements with semicolons, and improve readability through whitespace, indentation, multi-line statements, and code formatting with IntelliJ and Google Java conventions.

Master Java if statements with code blocks, else and else-if, using booleans and integers to control flow and print outcomes in score-based examples.

Learn how Java methods reduce code duplication by encapsulating reusable blocks. Declare and invoke public static void methods, and pass parameters and arguments to customize behavior and improve maintainability.

Create two Java methods to manage high scores: displayHighScorePosition prints a player's name and rank, and calculateHighScorePosition returns a number between 1 and 4 for a given score.

Learn to compare your IntelliJ code with downloaded solutions using side-by-side and unified views, highlight differences, and use local history to revert or restore earlier versions.

Explore in-browser coding exercises using Java 17 in this course, including a check number method that prints positive, negative, or zero in Udemy's editor.

Implement and test overloaded methods named convertToCentimeters, converting inches and feet and inches to centimeters using 1 inch = 2.54 cm and 1 foot = 12 inches, and verify with sample cases.

Develop and test two overloaded getDurationString methods to convert seconds into hours, minutes, and seconds, with validation and clear string output.

This lecture adds validation to the duration formatting methods, ensuring non-negative minutes and seconds within 0 to 59, with test cases and code refactoring for clarity.

Explore control flow statements in Java, including switch, if-else, for, while, and do-while, and learn how to decide what runs and when.

Explore the evolution from traditional to enhanced switch statements, covering switch expressions with arrow syntax, default handling, and the yield keyword for returning values, plus backwards compatibility notes.

Practice building a traditional switch statement to map letters a-e to NATO words, using cases, breaks, and a default, while contrasting with the enhanced switch.

Build and test a for loop based prime checker with an isPrime method. Use the modulo check, print primes, count them, and break after three primes for efficiency.

Complete the sum 3 and 5 challenge by looping 1 to 1000, printing numbers divisible by 3 and 5, breaking after five matches with final sum 225, using IntelliJ debugger.

Explore the for loop fundamentals in Java, including initialization, condition, and increment, with step-by-step iteration examples, pitfalls like infinite loops, and a note on the enhanced for loop.

Master while and do-while loops in Java by comparing them to for loops, learning how to use conditions, breaks, and continue to control iteration.

Create an isEvenNumber method using the remainder operator, then use a while loop to print even numbers from 5 to 20, skipping odds with continue and counting evens to five.

Recap the while loop and do-while loop, focusing on syntax, conditions, and execution order. Learn how continue and break affect iterations, and that do-while runs at least once.

Learn how a class acts as a template to create objects and how static and instance fields and methods differ, with wrappers for parsing numbers and interactive input.

Parse string data into numbers using Integer.parseInt and Double.parseDouble, then build an interactive console app that reads name and birth year with system.console or Scanner to compute age.

master the min max challenge by looping to prompt for numeric input, validate as numbers, track the running min and max, and display them when a non numeric entry ends.

Explore the fundamentals of object-oriented programming by learning classes, objects, and constructors, and examine inheritance, encapsulation, polymorphism, and composition.

Learn how object-oriented programming models real-world objects as software with state and behavior, using a car class to illustrate fields, methods, encapsulation, and access modifiers.

Build and test a bank account class with fields for account number, balance, customer name, email, and phone; include getters, setters, and deposit and withdraw methods that prevent negative balances.

Explore how constructors initialize objects in Java, including no-argument and parameterized constructors in the account class. Learn constructor overloading and how this keyword assigns fields during object creation.

Explore constructor overloading and chaining in Java, using this() to call another constructor from a no-argument constructor, forwarding values to a five-parameter constructor for consistent field initialization.

Create a Customer class with private name, credit limit, and email fields, expose getters, and implement three constructors (all fields, no-args, and name-email) using this() chaining, then test in main.

Explore references, objects, instances, and classes in Java using a house blueprint analogy; learn how references point to objects, and how multiple references share one object.

Compare static and instance variables in Java, noting that static variables are shared across instances and accessed via class name, while instance variables belong to each object and store state.

Explore how a plain old java object (pojo) stores data in fields, acts as a JavaBean or DTO, and uses constructors, getters, setters, and toString for data transfers.

Replace boilerplate pojo code with java records, immutable data carriers that auto generate constructors, accessors, and toString, while removing setters.

Explore inheritance in Java by extending the animal class to create a dog with attributes, constructors, and behaviors, using super calls, constructor chaining, and overriding to customize toString and move.

Master java inheritance by building a worker hierarchy with the extends keyword, from Worker to Employee with salaried and hourly subclasses, implementing constructors, get age, collect pay, terminate, and toString.

Explore Java text blocks for multi-line strings and master output formatting with print F and format methods. Learn to use format specifiers like %D and %F, control precision and width, apply platform line separators, and compare string format and formatted methods for readable, maintainable code.

Explore string manipulation methods, from cleanup operations like trim and indent to transformation methods such as join and concat, including substring, index of, and replace variants.

Compare strings and StringBuilder to show strings are immutable while StringBuilder is mutable, offering append, delete, insert, reverse, capacity management, and set length for efficient text manipulation.

Explore composition, encapsulation, and polymorphism to understand their roles in object-oriented programming and how to apply them in your Java projects.

Explore composition in Java by modeling a personal computer as a product with has-a relationships to a monitor, motherboard, and computer case, contrasting it with is-a inheritance.

Model a smart kitchen by composing IoT appliances and controlling them with set kitchen state and do kitchen work to brew coffee, order food, and wash dishes.

Encapsulation hides internal class details to protect data and simplify public interface, using private fields and controlled access. It warns against public fields in a player class and emphasizes constructors.

Create an encapsulated enhanced player by declaring private fields, implementing constructors with health validation (1–100), and exposing state through methods, preventing direct data access and preserving class integrity.

Practice encapsulation by building a printer class with toner, duplex settings, and pages printed; implement addToner and printPages with proper validation and getters.

Explore polymorphism in Java by creating a Movie base class and subclasses Adventure, Comedy, and Science Fiction. Observe runtime type and behavior via overridden watchMovie methods and dynamic binding.

Master the factory method for polymorphism by returning movie subclass instances from a getMovie method, driven by runtime type and a simple switch, to simplify calling code.

Explore polymorphism in Java by building a Car base class and GasPoweredCar, ElectricCar, and HybridCar subclasses, overriding start and run engine to execute different behaviors at runtime.

Master polymorphism by finalizing car inheritance and overriding start engine and run engine methods for gas-powered, electric, and hybrid cars, and test runtime behavior in a single main class.

Apply object-oriented programming to build a complete burger restaurant app using composition, inheritance, encapsulation, and polymorphism. Create meal orders with burgers, drinks, sides, toppings, and the deluxe burger price.

Extend the base burger to a deluxe version, add two extra toppings, and keep the meal price flat at eight dollars fifty, with toppings free.

Explore how packages organize related types, use import statements or fully qualified names, and manage access across packages, with practical IntelliJ examples.

Discover how arrays serve as the basic container to store multiple values of the same type in Java, a foundational step in the Java Masterclass.

Learn how to populate and loop through Java arrays, compare for and enhanced for loops, and print arrays using Arrays.toString while exploring object arrays and default values.

Create a program that generates a random integer array, prints the unsorted state, sorts it in descending order with a swap-based reverse sort, and prints the sorted result.

Explore foundational array concepts in Java, including zero-based indexing, creating arrays, default values, and common pitfalls like index out of bounds and loop errors, with practical examples.

Explore how arrays are reference types, where multiple references can point to the same memory, and how Java passes a copy of the reference to a method, mutating the array.

Master varargs in Java by converting between string arrays and variable arguments, and learn how main method signatures adapt for command-line inputs while exploring split and join.

Tackle the minimum element challenge by reading a comma delimited list of integers from the console, parsing them into an array, and finding the minimum with a dedicated findMin method.

Explore multi-dimensional arrays in Java, focusing on two-dimensional arrays as matrices, with nested arrays of varying lengths, and learn to declare, initialize, traverse with for loops, and print them.

Explore jagged and multi-dimensional arrays in Java by assigning outer arrays to hold inner arrays of varying sizes, using array initializers and new int[], and printing with Arrays.deepToString.

Explore how the ArrayList implements the List interface to provide a resizeable collection for grocery items. Use generics and the diamond operator for compile-time type checking.

Learn to declare typed array lists, use the diamond operator, and apply add, set, remove, and addAll, including converting arrays with List.of and understanding mutable versus immutable lists.

Compare arrays and ArrayLists side by side to learn their similarities, differences, and key methods. Understand sizing, mutability, and features like Arrays.asList, List.of, and array backing.

Build an interactive grocery list using ArrayList and Scanner with a menu to add, remove, and print a sorted, duplicate-free list after each operation.

Explore memory layout of arrays, arraylists, and linkedlists; understand capacity, reallocation, and Big O implications for add, remove, and traversal.

Explore linked lists in Java by adding and removing elements, leveraging LinkedList as a list, queue, double-ended queue, and stack, with methods like add, addFirst, offer, poll, and push.

Master how iterators traverse lists using next and hasNext, and leverage ListIterator for forward and backward movement, add and remove operations, while understanding the cursor between elements.

Build a LinkedList itinerary of Place records ordered by distance from Sydney, prevent duplicates, and navigate forward and backward with a ListIterator.

Create an interactive linked list navigator using ListIterator to move forward and backward through a places to visit itinerary, with a menu-driven interface, input handling, and print menu functionality.

Explore autoboxing and unboxing with arrays, varargs, and lists such as ArrayList and LinkedList, using Integer and Character wrappers, Arrays.toString, and List.of.

Build a bank application in Java that uses autoboxing and unboxing to manage customers and transactions, validate new customers, print formatted statements, and test behavior with edge cases.

Explore how to declare and use enums in Java, including predefined constants, ordinal and name methods, and random day selection with the values array.

Master enum usage by switching on DayOfTheWeek, using ordinal and name, formatting day names with string methods, and creating a Topping enum with a custom getPrice method and values() iteration.