Learn Core Java from Scratch: Hands-On Training – 2026

Definition and purpose of IDEs

Comparison of IDEs to text editors

Importance of using an IDE in Java development

Popular IDEs for Java development

Downloading and installing IntelliJ IDEA

Creating a new project in the IntelliJ IDEA

Writing and executing a simple Java program

Explanation of what data types and variables are

Importance of understanding data types and variables in programming

Explanation of primitive data types and their uses

Integer data types (byte, short, int, long)

Floating-point data types (float, double)

Character and boolean data types

Demonstration of how to declare and initialize variables of different primitive data types

Casting

Explanation of non-primitive data types (String, arrays, classes)

Comparison of primitive and non-primitive data types

Demonstration of how to declare and initialize variables of non-primitive data types

Explanation of variable naming conventions in Java

Explanation of variable scope

Demonstration of how variable scope affects program behavior

Using the System.out.print() and System.out.println() methods to write to the console

Examples of writing different data types to the console

Formatting output with printf() method

Using the Scanner class to read input from the console

Examples of reading different data types from the console

Arithmetic operators (e.g. +, -, *, /)

Comparison operators (e.g. ==, !=, >, <)

Logical operators (e.g. &&, ||, !)

Assignment operators (e.g. =, +=, -=)

Understanding operator precedence in expressions

Examples of how operator precedence affects the outcome of an expression

Common mistakes when using operators and expressions

Best practices for writing clear and efficient code using operators and expressions

Syntax and usage of if-else statements

Example of if-else statements in Java code

Nesting of if-else statements

Syntax and usage of switch statements

Example of switch statements in Java code

Differences between switch and if-else statements

Types of loops in Java (for, while, do-while)

Syntax and usage of each loop type

Examples of loops in Java code

Usage of break and continue

Tips for efficient looping

Definition of a method in Java

Syntax of declaring a method in Java

Types of methods (void, non-void)

Defining parameters for a method

Return types of methods

Method overloading

Method invocation

Parameter passing mechanism in Java

Recursive methods

Varargs in the methods

Creating and initializing arrays

Accessing and modifying array elements

Iterating through arrays

Common methods for arrays (length, sort, etc.)

Multidimensional arrays

Overview of the concept of strings in Java

Differences between string literals and string objects

String methods such as length(), charAt(), indexOf()

Immutability of strings and its implications

Using the + operator for concatenation

Using the StringBuilder and StringBuffer classes for concatenation

Compare strings using the equals() and equalsIgnoreCase() methods

Compare strings using the == operator and the compareTo() method

Syntax and usage of the String.format() method

Examples of formatting strings using placeholders and format specifiers

Understanding of string pool concept

How string pool works in Java

Definition and explanation of a class in Java

Creating a class and understanding its structure

Fields

Methods

Definition and explanation of an object in Java

Creating an object from a class

Understanding the relationship between classes and objects

Using the dot operator to access object methods and variables

Understanding the difference between an object's reference and its value

'static' keyword

Access modifiers

Initialization blocks

Nested classes

Getters and setters

Definition and explanation of constructors in Java

Types of constructors: default and parameterized

'this' keyword

How constructors are used when creating objects

Overview of interfaces in Java

Defining an interface

Implementing an interface

Extending an interface

Default and static methods in interfaces

Overview of abstract classes in Java

Defining an abstract class

Extending an abstract class

Abstract methods and concrete methods

Abstract classes vs concrete classes

Differences between interfaces and abstract classes

When to use interfaces and when to use abstract classes

Extending an abstract class and implementing an interface

Differences between "implements" and "extends"

Definition and explanation of inheritance in OOP

Examples of inheritance in real-world scenarios

How inheritance allows for code reuse and organization

Extending classes in Java

Understanding the relationship between parent and child classes

Overriding methods in child classes

Understanding the use of the "super" keyword

Understanding the "is-a" relationship in inheritance

Definition and explanation of polymorphism in OOP

How polymorphism allows for flexibility and dynamic behavior in code

Understanding the difference between overloading and overriding methods

Examples of polymorphism in use, such as with the "instanceof" operator

Understanding the use of the "final" keyword in classes and methods

Understanding the use of the "protected" access modifier

Understanding the difference between "composition" and "inheritance"

Understanding the use of inner classes and anonymous classes in polymorphism

Understanding the use of typecasting and downcasting

Definition of Encapsulation

Explanation of how encapsulation works

Explanation of public, private, protected and default access modifiers

Use of access modifiers in classes, methods and variables

Code examples of encapsulation in practice

Explanation of the acronym SOLID and its meaning

Definition and explanation of the Single Responsibility Principle

Definition and explanation of the Open-Closed Principle

Definition and explanation of the Liskov Substitution Principle

Definition and explanation of the Interface Segregation Principle

Definition and explanation of the Dependency Inversion Principle

Explanation of how Java handles memory management

The role of the garbage collector in removing unused objects

Overview of the Collection framework

Collections hierarchy

Understanding the different types of Collections (List, Set, Queue)

ArrayList

LinkedList

ArrayList vs LinkedList

Using Lists for data manipulation and retrieval

Performance considerations for Lists

Understanding the Set interface

HashSet

TreeSet

Using Sets for data manipulation and retrieval

Understanding set operations (union, intersection, difference)

Performance considerations for Sets

Understanding the Queue interface and its implementation classes

Using Queues for data manipulation and retrieval

Understanding queue operations (offer, poll, peek)

Performance considerations for Queues

Maps hierarchy

Understanding the Map interface and its implementation classes

Using Maps for data manipulation and retrieval

Understanding map operations (put, get, remove)

Performance considerations for Maps

Using the Iterator and ListIterator interfaces

Using foreach with Collections and Maps

Using the Comparator and Comparable interfaces

Using the Collections utility class

Using the Arrays utility class.

Explanation of what exceptions are in Java

The importance of exception handling in programming

Overview of the exception class hierarchy in Java

Explanation of the Throwable class

Understanding the difference between Error and Exception

Understanding the difference between Exception and RuntimeException

Syntax and usage of the try-catch statement

How to catch and handle specific exceptions

The use of multiple catch blocks

The finally block

Syntax and usage of the throw statement

When to use the throw statement

Syntax and usage of the throws statement

When to use the throws statement

Checked vs Unchecked exceptions

Examples of common exceptions in Java

How to prevent exceptions

How to handle exceptions properly

How to avoid common mistakes when handling exceptions

Overview of custom exceptions

Reasons for creating custom exceptions

Extending the Exception or RuntimeException class

Overriding the constructors

Adding additional methods and fields

Providing meaningful error messages

Throwing exceptions at the appropriate level of abstraction

Definition and purpose of generics

How generics improves type safety and reduces code duplication

Comparison with non-generic types

Syntax for creating generic classes and methods

Using the wildcard character "?"

Bounded type parameters

Creating and using generic classes such as List<T> and Map<K, V>

Using generic methods such as Collections.sort() and Arrays.asList()

Avoid using raw types

Pay attention to type erasure

Be cautious when using generic array types

Explanation of what enumerations are and how they are used in Java

Differences between enumerations and traditional constant variables

Syntax for defining an enumeration

Examples of defining an enumeration and using its values

How to use enumerations in control flow statements (i.e. switch)

How to use enumerations in object-oriented programming

Overview of the Enum class and its methods (i.e. values(), ordinal(), name())

Examples of using the Enum class methods in code

Overview of Input/Output (IO) and file handling in Java

Understanding streams and readers/writers

Differences between byte and character streams

Reading data from input streams

Using the InputStream and Reader classes

Examples of reading from the file system, network, and user input

Writing data to output streams

Using the OutputStream and Writer classes

Examples of writing to the file system, network, and console

Definition of serialization

Why and when to use serialization

Comparison of serialization and deserialization

Implementing the Serializable interface

Using the ObjectOutputStream and ObjectInputStream classes

Controlling serialization using the transient keyword

What is Multithreading

Concurrency vs. Parallelism

Processes vs. Threads

Advantages and disadvantages of Multithreading

Creating and starting threads

Difference between start() and run() methods

Thread states and life cycle

Thread priorities and scheduling

Daemon Threads

Why synchronization is needed

Synchronized methods and blocks

Monitors, wait(), notify(), and notifyAll()

Deadlocks and how to avoid them

Interrupting threads

InterruptedException

Interrupting non-interruptible threads

Inter-thread communication

Wait-notify mechanism

Guarded Blocks

Joining threads

Introduction to the Executor framework

Executor, ExecutorService, and ThreadPoolExecutor

Executor lifecycle methods

Submitting tasks to ExecutorService

CompletableFuture in Executor framework

Introduction to the Fork/Join Framework

RecursiveTask and RecursiveAction classes

ForkJoinPool and its methods

Divide-and-conquer approach

Task stealing and work balancing

Examples of using the Fork/Join Framework

Introduction to Thread Pools

Creating and managing Thread Pools

Types of Thread Pools

ThreadPoolExecutor in detail

What is thread safety

Atomic variables and classes

Synchronized collections

Volatile keyword

Introduction to Thread Local Variables

Why are they needed

ThreadLocal class and methods

Usage examples

Introduction to Lock Framework

ReentrantLock

ReadWriteLock

Lock conditions

Introduction to Thread Groups

ThreadGroup methods and constructors

Uncaught Exception Handler