Author

Java Architect Handbook

Focused on Java interview questions and practical article sharing, covering algorithms, databases, Spring Boot, microservices, high concurrency, JVM, Docker containers, and ELK-related knowledge. Looking forward to progressing together with you.

102

Articles

Likes

Views

Comments

Latest from Java Architect Handbook

100 recent articles max

Java Architect Handbook

Jan 11, 2026 · Backend Development

Why @Configuration + @Bean Overrides @Component in Spring Boot: Deep Dive and Version Differences

A detailed analysis shows that when a class is annotated with both @Configuration/@Bean and @Component, Spring creates only one bean—the one defined by @Configuration/@Bean—overriding the @Component definition, and explains how this behavior changed across Spring and Spring Boot versions.

Bean OverridingComponentSpring Boot

0 likes · 10 min read

Why @Configuration + @Bean Overrides @Component in Spring Boot: Deep Dive and Version Differences

Java Architect Handbook

Jan 10, 2026 · Backend Development

Boost API Speed 14× with a 3‑Level Cache Pyramid in Spring Boot

By combining a local Caffeine cache, a remote Redis layer, and a MySQL database into a three‑tier cache pyramid, this guide shows how to reduce API response time from 28 ms to 2 ms, cut CPU usage by 35 %, and achieve up to 14‑fold performance gains, complete with configuration, code, and monitoring tips.

CacheCaffeinePerformance Optimization

0 likes · 12 min read

Boost API Speed 14× with a 3‑Level Cache Pyramid in Spring Boot

Java Architect Handbook

Jan 9, 2026 · Databases

What Happens When MySQL AUTO_INCREMENT Runs Out? Prevention and Recovery Strategies

This article analyzes the interview focus on MySQL auto‑increment primary key exhaustion, explains the underlying mechanism, outlines preventive design choices and monitoring, and provides detailed emergency response options, best‑practice recommendations, and common pitfalls for robust database management.

Database DesignMonitoringScalability

0 likes · 9 min read

What Happens When MySQL AUTO_INCREMENT Runs Out? Prevention and Recovery Strategies

Java Architect Handbook

Jan 7, 2026 · Databases

When to Use DELETE, TRUNCATE, or DROP? A Deep Dive for Java Interviews

This article explains the fundamental differences between DELETE, TRUNCATE, and DROP, covering interview expectations, underlying mechanisms, performance impacts, transaction safety, best‑practice usage scenarios, and common pitfalls to help candidates choose the right command for any database task.

DELETEDROPDatabase

0 likes · 9 min read

When to Use DELETE, TRUNCATE, or DROP? A Deep Dive for Java Interviews

Java Architect Handbook

Jan 3, 2026 · Databases

When Should You Avoid JOINs in High‑Concurrency Systems?

The article analyzes a common Java interview question about using JOINs, explaining performance bottlenecks, scalability issues in distributed and micro‑service architectures, and offers practical guidelines and best‑practice alternatives for handling data associations efficiently.

Backend ArchitectureDatabase PerformanceJoin

0 likes · 9 min read

When Should You Avoid JOINs in High‑Concurrency Systems?

Java Architect Handbook

Jan 1, 2026 · Databases

COUNT(*), COUNT(1) or COUNT(column) in MySQL? Deep Interview Guide

This article explains the semantic differences, performance characteristics, and optimal usage scenarios of COUNT(*), COUNT(1), and COUNT(column) in MySQL 8.0+, covering engine behavior, indexing effects, common misconceptions, and practical best‑practice recommendations for interview preparation and real‑world development.

COUNTInterviewPerformance

0 likes · 10 min read

COUNT(*), COUNT(1) or COUNT(column) in MySQL? Deep Interview Guide

Java Architect Handbook

Dec 31, 2025 · Backend Development

Mastering API Rate Limiting with Spring Interceptor and Redis

This article walks through building a Spring MVC interceptor that leverages Redis to enforce per‑IP request limits, explains configurable parameters, shows how to apply protection selectively via mapping rules or custom annotations, and discusses practical pitfalls such as sliding‑window logic, path‑parameter handling, and real‑IP detection.

API SecurityInterceptorJava

0 likes · 20 min read

Mastering API Rate Limiting with Spring Interceptor and Redis

Java Architect Handbook

Dec 30, 2025 · Operations

Master Prometheus: Installation, Configuration, PromQL Basics, and Grafana Integration

This comprehensive guide walks you through the background, architecture, and technology selection for monitoring, then details step‑by‑step installation of Prometheus, configuring exporters for Linux, MySQL, and Java applications, introduces core PromQL concepts, and shows how to integrate and visualize data with Grafana.

GrafanaJavaLinux

0 likes · 33 min read

Master Prometheus: Installation, Configuration, PromQL Basics, and Grafana Integration

Java Architect Handbook

Dec 29, 2025 · Fundamentals

When Does a.equals(b) Throw NullPointerException? Understanding Java Equality

This article explains how Java handles null and empty‑string comparisons with a.equals(b), Objects.equals(a, b), and the == operator, detailing the resulting return values, exception behavior, and the underlying source code logic.

JavaNull HandlingObjects.equals

0 likes · 7 min read

When Does a.equals(b) Throw NullPointerException? Understanding Java Equality

Java Architect Handbook

Dec 28, 2025 · Databases

Mastering Redis Data Types: Core Concepts, Use Cases, and Common Pitfalls

This article breaks down Redis's nine data types, explains the underlying structures and typical scenarios for each, compares best‑practice usage, highlights interview focus points, and warns about common misconceptions to help developers choose the most efficient storage solution.

Best PracticesData TypesDatabase

0 likes · 10 min read

Mastering Redis Data Types: Core Concepts, Use Cases, and Common Pitfalls