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Java Companion

Dec 29, 2025 · Backend Development

Avoid OOM: EasyExcel Best Practices for Exporting Millions of Rows (with Ready‑to‑Use Helper)

This article explains why exporting large Excel files with EasyExcel can cause OOM, CPU blockage, and slow responses, and demonstrates a pagination‑query plus batch‑write solution with reusable helper classes, performance benchmarks, dynamic page sizing, async export, multi‑sheet and template techniques, and a concise best‑practice checklist.

AsyncJavaPagination

0 likes · 15 min read

Avoid OOM: EasyExcel Best Practices for Exporting Millions of Rows (with Ready‑to‑Use Helper)

Java Companion

Dec 28, 2025 · Backend Development

SpringBoot vs Nginx: Five Implementation Options vs One Directive – Which Is the True Anti‑Hotlinking Champion?

An in‑depth comparison of anti‑hotlinking techniques shows how Nginx can enforce protection with a single directive in milliseconds, while SpringBoot offers five approaches—Filter, Interceptor, Nginx config, signed URL, and hybrid strategy—each with different performance, security, and maintenance trade‑offs.

FilterInterceptorNginx

0 likes · 14 min read

SpringBoot vs Nginx: Five Implementation Options vs One Directive – Which Is the True Anti‑Hotlinking Champion?

Java Companion

Dec 27, 2025 · Cloud Native

Is Minio Turning Paid? 5 Free Distributed Storage Alternatives You Should Consider

The article explains Minio's recent licensing shift to AGPLv3, why it matters for SaaS and proprietary software vendors, and presents five open‑source distributed storage systems—SeaweedFS, Garage, Ceph, GlusterFS, and OpenStack Swift—detailing their licenses, deployment complexity, performance characteristics, and suitable use cases.

CephGlusterFSMinio

0 likes · 21 min read

Is Minio Turning Paid? 5 Free Distributed Storage Alternatives You Should Consider

Java Companion

Dec 25, 2025 · Backend Development

Druid Crashed in Production? How to Optimize the Spring Boot Connection Pool

The article explains why Druid can fail in a live Spring Boot service and provides a comprehensive, step‑by‑step optimization guide covering core pool parameters, monitoring setup, security hardening, leak detection, dynamic tuning, and best‑practice pitfalls to achieve stable, high‑performance database connections.

Connection PoolDruidJava

0 likes · 12 min read

Druid Crashed in Production? How to Optimize the Spring Boot Connection Pool

Java Companion

Dec 23, 2025 · Backend Development

Three Spring Async Streaming APIs to Eliminate Timeout Issues

This article explains how to handle long‑running Spring endpoints by using three asynchronous streaming tools—ResponseBodyEmitter, SseEmitter, and StreamingResponseBody—showing their appropriate scenarios, configuration details, and complete code examples that keep the servlet thread free and avoid timeout problems.

AsyncResponseBodyEmitterSpring

0 likes · 9 min read

Three Spring Async Streaming APIs to Eliminate Timeout Issues

Java Companion

Dec 21, 2025 · Backend Development

Eliminate Messy Login Logic: Unified Multi‑Channel Authentication with Spring Boot Factory & Strategy Patterns

This article demonstrates how to replace tangled if‑else login code with a clean Spring Boot solution that combines the Factory and Strategy patterns, enabling easy addition of multiple authentication methods such as password, WeChat, SMS, and future providers while improving extensibility, readability, and testability.

BackendFactory PatternJava

0 likes · 12 min read

Eliminate Messy Login Logic: Unified Multi‑Channel Authentication with Spring Boot Factory & Strategy Patterns

Java Companion

Dec 19, 2025 · Backend Development

Spring ApplicationEvent Listeners: A Lightweight Asynchronous Alternative to MQ

This article explains how Spring ApplicationEvent listeners can replace heavyweight message queues for high‑traffic scenarios, showing event class design, publishing and handling code, real‑world performance data, common pitfalls, and best‑practice guidelines for reliable asynchronous processing.

ApplicationEventBest Practiceseventlistener

0 likes · 9 min read

Spring ApplicationEvent Listeners: A Lightweight Asynchronous Alternative to MQ

Java Companion

Dec 18, 2025 · Backend Development

Building a High‑Performance Sensitive‑Word Filter with SpringBoot and DFA

This article explains why traditional string‑search and regex methods struggle with large keyword sets, introduces the deterministic finite automaton (DFA) approach using a Trie structure for linear‑time matching, provides full Java implementations, and discusses real‑world applications and advanced optimizations such as double‑array Tries, Aho‑Corasick, and sharding with Bloom filters.

DFAJavaSensitiveWordFilter

0 likes · 17 min read

Building a High‑Performance Sensitive‑Word Filter with SpringBoot and DFA

Java Companion

Dec 16, 2025 · Backend Development

Why Is the First Feign Call So Slow? Understanding Ribbon’s Lazy Loading and Eager‑Load Fix

The article explains that the initial Feign request is slow because Ribbon lazily creates its client and fetches the service list at first use, and shows how enabling Ribbon’s eager‑load mode pre‑warms the client to eliminate the delay.

Eager LoadFeignRibbon

0 likes · 6 min read

Why Is the First Feign Call So Slow? Understanding Ribbon’s Lazy Loading and Eager‑Load Fix

Java Companion

Dec 16, 2025 · Databases

Why Choose PostgreSQL Over MySQL? A Detailed Feature Comparison

The article compares PostgreSQL and MySQL across data types, sequence handling, extensions, monitoring tools, replication, licensing, and MVCC implementation, showing why many Chinese tech giants prefer PostgreSQL for complex, high‑availability workloads while acknowledging MySQL’s strengths in simple web scenarios.

Database ComparisonFeature analysisMVCC

0 likes · 8 min read

Why Choose PostgreSQL Over MySQL? A Detailed Feature Comparison