🚀 CodingCure Premium Backend Course

Java Backend Master Program

Master Core Java, Spring Boot, Microservices, Security, Docker, AWS & Real-Time Backend Development with Industry Level Concepts

☕ Core Java — Build Strong Backend Foundation

🔹 OOPS Beyond Theory

  • Why OOPS changed software development
  • Real-time problems solved using OOPS
  • Encapsulation in Banking Applications
  • Inheritance Problems & Tight Coupling
  • Composition vs Inheritance (Real Project Scenarios)
  • Polymorphism in Payment Gateway Systems
  • Abstraction
  • SOLID Principles Introduction

🔹 JVM Architecture Deep Dive

  • How Java Code Executes Internally
  • JVM Components Explained Visually
  • Heap Memory vs Stack Memory
  • Metaspace vs PermGen
  • ClassLoader Internal Working
  • Object Creation Flow Inside JVM
  • Why StackOverflowError Happens
  • Why OutOfMemoryError Happens
  • Memory Leaks in Real Applications

🔹 Garbage Collector Internals

  • Why Garbage Collection Needed
  • How Objects Become Eligible for GC
  • Minor GC vs Major GC
  • Stop The World Event
  • Serial GC vs Parallel GC vs G1 GC
  • How Modern JVM Optimizes Memory
  • GC Tuning Basics

🔥 Multithreading Deep Dive

🔹 Why Multithreading?
  • Why Single Thread Becomes Slow
  • Real-Time Backend Processing Examples
  • How Applications Handle Millions of Requests
🔹 Synchronization Deep Dive
  • Race Conditions Explained
  • Critical Section Problem
  • synchronized Keyword Internals
  • Object Lock vs Class Lock
  • Deadlock Detection & Prevention
  • volatile Keyword
  • Atomic Classes

🔹 Why Executor Framework Came?

  • Problems with Manual Thread Creation
  • Thread Pool Internal Working
  • FixedThreadPool vs CachedThreadPool
  • Future & Callable
  • Real-Time Async Processing

🔹 CompletableFuture Deep Dive

  • Why Future Was Not Enough
  • Async Programming in Modern Java
  • Parallel API Calls
  • Non-Blocking Backend Processing
  • Chaining Async Operations
  • Exception Handling in Async Flow
  • Real Project Use Cases

📦 Collections Internal Working

🔹 Why Collections Framework?

  • Problems with Arrays
  • Dynamic Data Handling

🔹 HashMap Internal Working

  • Bucket Structure Explained
  • Hashing Algorithm
  • Collision Handling
  • equals() vs hashCode()
  • LinkedList to Tree Conversion

🔹 ConcurrentHashMap

  • Why HashMap Fails in Multithreading
  • Segment Locking
  • Thread-Safe Collections
  • Internal Concurrency Optimization

🔹 Immutable Objects

  • Why Immutable Objects Are Powerful
  • String Immutability Internals
  • Creating Custom Immutable Classes
  • Immutable Collections
  • Real Benefits in Multithreading

🚀 Java 8 Mastery

🔹 Why Java 8 Changed Java Industry

  • Functional Programming Introduction
  • Lambda Expressions
  • Functional Interfaces
  • Stream API Internal Working
  • Parallel Streams
  • Method References
  • Optional Class
  • Date & Time API

🔹 Stream API Deep Dive

  • map vs flatMap
  • filter vs reduce
  • Grouping & Partitioning
  • Stream Pipeline Internals
  • Real-Time Data Processing
  • Most Important Interview Related Questions Discussion

🏗️ Design Patterns Used in Real Projects

🔹 Singleton Pattern

  • Why Singleton Needed
  • Thread-Safe Singleton
  • Singleton Problems

🔹 Factory Pattern

  • Object Creation Problem
  • Loose Coupling
  • Factory Pattern in Spring Framework

🔹 Strategy Pattern

  • How we design our classes
  • Dynamic Runtime Behavior Change
  • Payment System Real Example

🔹 Builder Pattern

  • Constructor Problems
  • Immutable Object Creation
  • Builder Pattern in Enterprise Applications

🌱 Spring Boot & Spring Internals

🔹 Why Spring Framework?

  • Tight Coupling Issues
  • Enterprise Application Challenges

🔹 Spring Architecture Internals

  • IOC Container Internal Working
  • Dependency Injection Explained Internally
  • BeanFactory vs ApplicationContext
  • How Spring Creates Objects

🔹 Bean Lifecycle Deep Dive

  • Bean Creation Flow
  • Bean Initialization
  • @PostConstruct & @PreDestroy
  • Bean Scopes
  • Singleton Bean Internals

🔹 @Configuration vs @Component

  • Why Both Exist
  • Proxy Object Creation
  • Internal Difference
  • Real Interview Questions

🔹 Spring Boot Internals

  • Why Spring Boot Became Popular
  • Auto Configuration Internals
  • Starter Dependencies
  • Embedded Tomcat Working
  • Application Startup Flow

🔹 @SpringBootApplication Breakdown

  • @Configuration
  • @EnableAutoConfiguration
  • @ComponentScan
  • Internal Flow Explained

🔐 Spring Security + JWT Authentication

🔹 Why Security Needed?

  • Authentication vs Authorization
  • Session vs Token-Based Authentication

🔹 JWT Authentication Deep Dive

  • Why JWT Came
  • Stateless Authentication
  • JWT Structure
  • Access Token vs Refresh Token
  • JWT Filter Internal Flow
  • Spring Security Filter Chain
  • Role-Based Authorization
  • Secure REST APIs

🌍 Microservices Architecture

🔹 Monolith vs Microservices

  • Real Industry Comparison
  • Scaling Problems in Monolith
  • Independent Deployment
  • Fault Tolurance

🔹 Microservices Design Principles

  • Single Responsibility
  • Database Per Service
  • Loose Coupling
  • High Cohesion
  • Event-Driven Architecture

🔗 Service Communication

🔹 RestTemplate vs WebClient

  • Why RestTemplate Became Limited
  • Blocking vs Non-Blocking Calls
  • Reactive Programming Basics
  • WebClient Internal Working
  • Async Service Communication
  • Real Performance Comparison

🛰️ Service Discovery

🔹 Eureka Server

  • Why Service Discovery Needed
  • Dynamic Service Registration
  • Load Balancing Basics

🔹 API Gateway

  • Why API Gateway Came
  • Centralized Routing
  • Authentication Handling
  • Request Filtering

🔹 Spring Cloud Gateway

  • Dynamic Routing
  • Gateway Filters
  • Rate Limiting

⚡ Resilience & Fault Tolerance

🔹 Circuit Breaker (Resilience4j)

  • Why Distributed Systems Fail
  • Circuit Breaker States
  • Fallback Mechanism

🔹 Retry Mechanism

  • Temporary Failure Handling
  • Retry Strategies
  • Retry with Backoff

🔹 Timeout Handling

  • Why Timeout Matters
  • Preventing Resource Exhaustion
  • API Failure Management

🚦 Rate Limiting

  • Why APIs Need Protection
  • Preventing API Abuse
  • Gateway-Level Rate Limiting

🔄 Saga Design Pattern

🔹 Why Distributed Transactions Fail

  • Problems with Traditional Transactions
  • Eventual Consistency

🔹 Choreography-Based Saga

  • Event-Driven Communication
  • Kafka-Based Workflow
  • Decentralized Transactions

🔹 Orchestration-Based Saga

  • Centralized Transaction Coordinator
  • Workflow Management
  • Compensation Transactions

⚡ Apache Kafka & Event-Driven Architecture

🔹 Kafka Fundamentals & Theory

  • What is a Messaging System? (Point-to-Point vs. Pub/Sub)
  • Why Kafka? What problems does it solve?
  • Kafka Architecture Overview
  • McDonald's Analogy for Clusters, Brokers, and Zookeeper

🔹 Core Kafka Concepts Demystified

  • Events, Event Keys, Event Values, and Timestamps
  • Kafka Topics and Partitions explained
  • How Offsets work
  • Leader and Follower roles for high availability
  • How to guarantee processing order using Event Keys

🔹 Hands-On Coding with Spring Boot

  • How to install and run Kafka locally (Mac/Linux)
  • Creating Kafka Topics
  • Building a Kafka Producer in Spring Boot using KafkaTemplate
  • Sending JSON messages with serialization
  • Building a Kafka Consumer in Spring Boot
  • Real-time data flow from end-to-end

⚙️ Config Server

  • Why Centralized Configuration Needed
  • Dynamic Configuration Management
  • Environment-Based Configurations

🐳 CI/CD & Deployment

🔹 Docker Containerization

  • Why Docker Changed Deployment
  • VM vs Container
  • Docker Image vs Container
  • Dockerfile Deep Dive
  • Multi-Stage Builds

🔹 CI/CD Pipeline

  • Why Automation Needed
  • GitHub Actions Workflow
  • Automated Build & Deployment
  • Testing Pipeline
  • Production Deployment Flow

☁️ AWS Deployment

🔹 EC2 Deployment

  • Hosting Spring Boot Applications
  • Linux Server Basics

🔹 S3 Storage

  • File Upload Systems
  • Static Resource Hosting
  • Secure File Access

🔹 AWS RDS Database

🎯 Bonus Real-Time Topics

  • API Testing using Postman
  • Exception Handling Best Practices
  • Clean Code Practices
  • Real-Time Project Architecture
  • Interview Preparation Sessions
  • Resume Building Guidance
  • Mock Interviews
  • Real Enterprise Project Development