The Java Knowledge Ocean

The Java Knowledge Ocean

The Most Comprehensive Explanation of Session, Cookie, Token, and JWT on the Entire Network!🔥
Understanding HTTP statelessness, Cookie security flags, Session limitations in distributed systems, and the mechanics of Access/Refresh Tokens
 • Dylan Smith
These Five Most Commonly Used Encryption Algorithms You Must Master!😉
Understanding irreversible, symmetric, and asymmetric encryption mechanics, Java code implementations, and HTTPS fundamentals
 • Dylan Smith
Interviewer: Why Must the Password Be Reset When Forgotten Instead of Directly Telling Me the Original Password?
Demystifying Password Security: One-Way Hashing, Salting, and the Mechanics Behind Password Resets
 • Dylan Smith
Inteview: Why do You Need to Use Message Queue?
Why asynchronous architecture speeds up systems, what trade-offs it introduces, and how to decide if you actually need it
 • Dylan Smith
Distributed Rate Limiting, Explained: From a Boba Shop Queue to Production Java, 4 Classic Algorithms and a Complete Architecture Overview
A complete guide covering 4 classic algorithms, runnable Jedis/Redisson/Gateway implementations, and high-concurrency pitfalls.
 • Dylan Smith
How Does Spring Boot Implement Asynchronous Programming? This Is How Masters Do It!
Why default @Async causes memory leaks and how to build production-ready thread pools with AsyncConfigurer.
 • Dylan Smith
15 Essential Rules for Designing High-Performance and Robust APIs
A complete developer guide covering rate limiting, thread isolation, async processing, and transaction optimization in Java.
 • Dylan Smith
System Design: Principles and Practices of Idempotency Control
From unique indexes to generic idempotency tables: 5 proven strategies to prevent double deduction in distributed systems
 • Dylan Smith
​Real-Time Message Push Solutions Unveiled: From Polling to WebSocket, Which is Your Best Choice?
A comprehensive breakdown of Short Polling, Long Polling, SSE, WebSocket, Netty, and MQTT with Java code examples.
 • Dylan Smith
AOP + Guava RateLimiter: How I Implemented Elegant Rate Limiting with Annotations?
A step-by-step guide to building non-intrusive, annotation-driven QPS control in Spring Boot.
 • Dylan Smith
JDK 8 → 17 → 21 → 25: The Key Leaps Across Four LTS Generations, Explained at Once
The article combines extensive code and charts for explanation.
 • Dylan Smith
How to Design a Notification System for One Billion Users? War Stories from the Trenches
A classic system design interview question, plus real-world engineering lessons learned. Starting from a dumb cron job, scaling up to a billion users …
 • Dylan Smith
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