Focus on Java-related technologies: SSM, Spring ecosystem, microservices, MySQL, MyCat, clustering, distributed systems, middleware, Linux, networking, multithreading. Occasionally cover DevOps tools like Jenkins, Nexus, Docker, and ELK. Also share technical insights from time to time, committed to Java full-stack development!
The article explains why using the vague term “user” in software design creates hidden security flaws, illustrates the problem with examples from ticket booking, Unix, and SaaS systems, and urges early terminology planning to avoid costly redesigns.
This guide explains how to load external JAR files into the JVM, configure SpringBoot to recognize them, and choose among several class‑loading strategies—including expanding the classpath, using the loader.path parameter, or implementing a custom classloader—while providing Maven configuration examples and code snippets.
This article reveals how SpringBoot's out‑of‑the‑box defaults—such as Tomcat connection limits, HikariCP pool size, JPA lazy loading, Jackson timezone handling, logging, file upload limits, async thread pools, static resource caching, and transaction timeouts—can cause performance bottlenecks and stability issues in production, and provides concrete configuration recommendations to prevent them.
This article walks through eight practical MySQL optimization techniques—including smarter LIMIT usage, avoiding implicit type conversion, rewriting UPDATE/DELETE with JOINs, handling mixed sorting, replacing EXISTS with joins, pushing predicates, narrowing result sets early, and leveraging WITH clauses—to dramatically reduce query execution time from seconds to milliseconds.
This article explains how to implement an online‑user counting feature using Redis sorted sets (zset) by leveraging the four core commands zadd, zrangeByScore, zremrangeByScore, and zrem, with Java/Spring code examples and optional browser‑fingerprinting for unauthenticated visitors.
This guide explains why traditional Java apps require restarts for config changes, introduces Spring Boot's @RefreshScope for hot configuration updates, details its core principles, provides step‑by‑step implementation, best practices, troubleshooting tips, and advanced use cases such as dynamic feature toggles and logging level adjustments.
Using the literal string "null" as a username can cause validation failures, database pollution, security risks, and endless debugging, but with proper checks, front‑end validation, database constraints, and clear logging you can avoid these hidden bugs.
This article explains Java 8's functional interfaces—including Function, Supplier, Consumer, and Runnable—showing how to replace verbose if‑else and exception handling with concise lambda expressions, and provides reusable utility interfaces for branching, present‑or‑else logic, and exception throwing.
Feat is a high‑performance Java web service framework that offers a SpringBoot‑like development experience while delivering faster startup, lower memory usage, higher request throughput, and built‑in AI‑native and cloud‑native capabilities, making it a compelling alternative for modern backend development.
This article explains how to handle downstream API rate limits that differ per platform by interleaving requests with a weighted round‑robin algorithm, shows the pitfalls of simple sleep‑based throttling, and provides complete Java code for a practical implementation.
