Java Core Guide: Key Features, OOP, Collections & More

• What are variables;

• Key characteristics of variables;

• Types of variables;

• Variable Naming Rules

• Primitives

• Suffixes for number types;

• Explicit and implicit casting.

• If-else statements

• Ternary operator

Switch statements

for loops

• while loops

• do-while loops

• Objects and primitives in Java

• Autoboxing and Unboxing in Java

• Primitives vs Wrapper Classes

• Exceptions

• Hierarchy of Exceptions in Java

• Types of Exceptions

• try-catch-finally block

• What is enum?

• How to declare an enum

• Using enums in switch statement

• How to compare enums

• Enum methods

• Enums with methods and fields

• Enums implementing interfaces

• What is Serialization

• Conditions for Serialization

• serialVersionUID

• Deserialization

• Where Serialization can be used

• Limitations of Serialization

• What is Java Memory Model

• Primary memory areas

• Java Memory Components

• Garbage collector

Agenda:

• What is OOP?

• Access modifiers in Java, examples, its role in OOP

• Key components of OOP

• Examples of OOP in real life

• What is class?

• Why do we need to use OOP?

• Core principles of OOP

Agenda:

• What is Inheritance?

• Why is Inheritance Needed?

• Example of Inheritance

• Drawbacks of Inheritance

Agenda:

• Encapsulation definition

• Key Aspects of Encapsulation

• Take a look at an example

• Benefits of Encapsulation

• What is Polymorphism?

• The goal of Polymorphism

• Types of Polymprphism

• Overloading vs Overriding

• Definition of abstract class

• Key Characteristics of an Abstract Class

• What is an Interface?

• Key Characteristics of an Interface

• Peculiarities and differences of Abstract Classes and Interfaces

• What is Abstraction in OOP?

• Key idea of abstraction

• Example of Abstraction

• How is Abstraction Achieved in OOP

• Anonymous class

• Benefits of Abstraction

• Constructors

• Static blocks

• Instance Initialization Blocks

• Order of execution

• Constructor overloading

• super keyword

• What is generics

• Generic class

• Generic method

• Bounded type parameters

• Wildcards

• Erasure in Generics

• String

• String pool

• Comparing Strings

• String methods

• StringBuilder

• StringBuffer

• When to use each

• ArrayList

• LinkedList

• What is equals and hashcode methods

• equals and hashcode contracts

• Common mistakes to avoid

• Best Practices for equals() and hashCode()

• HashMap

• HashSet

• Comparator

• Comparable

• When to use each

• TreeMap

• TreeSet

• Iterator key methods

• ConcurrentModificationException

• Why use an iterator

• ListIterator

• Iterable

• What is LinkedHashSet

• How does it work

• Advantages of LinkedHashSet

• CopyOnWriteArrayList

• What is CopyOnWriteArrayList

• Why is it Needed?

• How Does It Work?

• When to Use CopyOnWriteArrayList?

• Drawbacks

  
  

• Lambdas

• Optional

• Streams

• var keyword

• New factory methods for collections

• New String methods

• New optional methods

• switch expressions,

• pattern matching,

• text blocks

• records

• sealed classes