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Full-Stack Dev Study Guide

6-Week Java Backend Interview Study Plan

6-Week Study Plan

Section titled “6-Week Study Plan”

Week 1 - Core Java

Section titled “Week 1 - Core Java”

Focus areas:

  • Java 8+ features
  • Collections internals
  • Multithreading & Concurrency
  • JVM internals
  • Garbage Collection
  • Streams, Optional, CompletableFuture

Daily schedule:

2 hours - Concepts
1 hour  - Coding
1 hour  - Interview Questions

Week 2 - Spring Boot

Section titled “Week 2 - Spring Boot”

Topics:

  • IoC
  • Dependency Injection
  • Bean Lifecycle
  • Auto Configuration
  • Spring MVC
  • DispatcherServlet
  • Filters vs Interceptors
  • Exception Handling
  • Spring Data JPA
  • Transactions

Week 3 - MySQL

Section titled “Week 3 - MySQL”

Topics:

  • Indexes
  • Composite Index
  • Covering Index
  • Query Optimization
  • EXPLAIN Plan
  • Transactions
  • ACID
  • Isolation Levels
  • Deadlocks

Week 4 - System Design

Section titled “Week 4 - System Design”

Practice:

  • URL Shortener
  • Payment System
  • Rate Limiter
  • File Upload Service
  • Notification System

Concepts:

  • Load Balancer
  • Cache
  • API Gateway
  • Redis
  • Kafka
  • CAP Theorem
  • Eventual Consistency

Week 5 - Microservices

Section titled “Week 5 - Microservices”

Topics:

  • Monolith vs Microservices
  • Service Discovery
  • API Gateway
  • Circuit Breaker
  • Saga Pattern
  • Distributed Transactions
  • Feign Client
  • Spring Cloud

Week 6 - Coding Practice

Section titled “Week 6 - Coding Practice”

Focus on:

  • Arrays
  • Strings
  • HashMap
  • Sliding Window
  • Two Pointer
  • Heap
  • LRU Cache

Project Discussion Structure

Section titled “Project Discussion Structure”
  1. Project Overview
  2. Architecture
  3. Responsibilities
  4. Technical Challenges
  5. Business Impact

Suggested talking points:

  • Explain domain.
  • Describe architecture.
  • Highlight ownership.
  • Discuss production issues solved.
  • Quantify improvements.

Architecture & Tooling

Section titled “Architecture & Tooling”
Tool Usage
Redis Caching, Rate Limiting
Kafka Event Streaming
Docker Containerization
Kubernetes Orchestration
ELK Logging

Interview Tips

Section titled “Interview Tips”

For senior roles, always explain:

  • Internal implementation
  • Trade-offs
  • Performance implications
  • Production experience
  • Scaling considerations

Example:

Instead of saying:

HashMap stores key-value pairs.

Explain:

  • Uses hashing
  • Stores entries in buckets
  • Handles collisions
  • Treeifies buckets after threshold (Java 8+)

Key Takeaways

Section titled “Key Takeaways”
  • Use the 6-week structure to sequence study: Core Java, Spring Boot, MySQL, System Design, Microservices, then dedicated coding practice.
  • Structure project discussions around overview, architecture, responsibilities, challenges, and quantified business impact.
  • Senior interviews reward explaining internals and trade-offs, not just reciting API behavior.