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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
This article explains why fine‑grained permission management is essential for data security, walks through classic RBAC, role‑inheritance (RBAC1), constrained RBAC (RBAC2), user groups, organization‑based and position‑based roles, and presents both standard and ideal database schemas for implementing these models.
