Java SE 17 – Practice Repository

This repository contains my hands-on practice while preparing for the Oracle Certified Professional: Java SE 17 Developer exam.
Each branch corresponds to a specific module or concept from the certification track.
The goal is to build a solid understanding of the Java language from fundamentals to advanced features.

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📚 Modules & Branch Structure

Below is the complete mapping of modules and the corresponding branches where applicable.

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🔹 Module 1 – Introduction to Java

Concepts:

• Java origins, ecosystem, and use cases
• Platform independence and provider neutrality
• Object-oriented programming fundamentals
• Java syntax and coding conventions
• main method structure
• Compilation & execution workflow (javac / java)

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🔹 Module 2 – Primitive Types, Operations & Flow Control

Concepts:

• Primitive types and literals
• Operators and primitive casting
• Math class usage
• Flow control (if, switch, loops)
• JShell for rapid prototyping

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🔹 Module 3 – Text, Date/Time & Numeric Objects

Concepts:

• String, text blocks, StringBuilder
• Wrapper classes
• Conversions between Strings and primitives
• BigDecimal
• Date/time API (LocalDate, LocalDateTime, Duration, etc.)
• Localization and formatting (Locale, NumberFormat, DateTimeFormatter)

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🔹 Module 4 – Classes and Objects

Branch: practice-4
Concepts:

• Classes & objects
• Methods, fields, constructors
• Access modifiers
• Object lifecycle and memory basics

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🔹 Module 5 – Improved Class Design

Branch: practice-5
Concepts:

• Method overloading
• Constructors & initialization
• Encapsulation & immutability
• Enumerations (enum)
• Parameter passing (pass-by-value)
• Memory allocation & cleanup (stack vs heap)

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🔹 Module 6 – Inheritance, Records & Modern OO

Branch: practice-6
Concepts:

• Class inheritance & polymorphism
• Method overriding
• Records
• Sealed classes
• Pattern matching with instanceof

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🔹 Module 7 – Interfaces & Generics

Branch: practice-7-interfaces-generics
Concepts:

• Interfaces, default & static methods
• Functional interfaces basics
• Generics (classes, methods, bounded types)
• Polymorphism with abstraction

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🔹 Module 8 – Arrays & Loops

Branch: practice-8-arrays-loops
Concepts:

• Arrays (1D/2D)
• Looping constructs
• Basic data iteration and transformations

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🔹 Module 9 – Collections Framework

Branch: practice-9-collections
Concepts:

• Collections API: List, Set, Map
• Iterators
• Sorting with Comparator & Comparable

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🔹 Module 10 – Nested Classes & Lambda Expressions

Branch: practice-10-nested-classes-and-lambda-expressions
Concepts:

• Inner & nested classes
• Anonymous classes
• Lambda expressions
• Functional programming patterns

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🔹 Module 11 – Java Streams API

Branch: practice-11-Java-Streams-API
Concepts:

• Stream pipelines
• Intermediate operations (map, filter, sorted, etc.)
• Terminal operations (collect, reduce, etc.)
• Functional data processing

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🔹 Module 12 – Exception Handling, Logging & Debugging

(Current module)
Concepts:

• Exception hierarchy
• Throwing & handling exceptions
• Custom exceptions
• try-with-resources
• Logging APIs (java.util.logging, SLF4J basics)
• Debugging techniques

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🔹 Module 13 – Java I/O API (Upcoming)

Concepts:

• Streams (byte & character)
• File I/O
• NIO.2 (Path, Files, directory operations)
• Serialization basics

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🔹 Module 14 – Concurrency & Multithreading (Upcoming)

Concepts:

• Threads & executors
• Synchronization
• Concurrency utilities (CompletableFuture, ConcurrentHashMap)
• Thread-safe patterns

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🔹 Module 15 – Modules & Deployment (Upcoming)

Concepts:

• Java Platform Module System (JPMS)
• module-info.java
• Packaging & deployment
• JAR structure

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📎 Appendixes (Reference Topics)

A – Annotations

• Built-in & custom annotations
• Retention policies
• Target types

B – JDBC (Java Database Connectivity)

• Connecting to databases
• Statements & prepared statements
• Transactions

C – Java Security

• Cryptography basics
• Secure coding practices
• Permissions & policies

D – Advanced Generics

• Wildcards
• Type inference
• Generic patterns

E – Oracle Cloud Deployment

• Packaging applications
• Deploying Java workloads on OCI

F – Miscellaneous Java Topics

• Additional utilities and APIs
• Best practices and edge cases

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🎯 Repository Purpose

• Strengthen core and advanced Java SE knowledge
• Track progress through the Oracle Java SE 17 certification curriculum
• Serve as a long-term reference for clean, modular Java code
• Complement real-world project experience (Spring Boot, microservices, etc.)

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🛠️ Environment

• Java 17
• Pure Java SE
• Works with IntelliJ IDEA, VS Code.
• Compilable with javac and runnable with java

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📌 Notes

This repository is not a full application but a structured learning workspace.
Future updates will include per-branch READMEs summarizing the concepts practiced.