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This article walks through building a distributed image captcha login for Spring Boot applications, contrasting traditional session‑based approaches with a front‑end/back‑end separated design that stores captcha codes in Redis, generates images via Kaptcha, and returns tokens to the client.
The article examines the challenges of achieving distributed consistency when a business operation writes to MySQL and external systems, analyzes failure scenarios, and presents a step‑by‑step solution that splits the large transaction into small, retryable tasks with Spring afterCommit optimization.
The article explains the concepts of cache penetration, avalanche, and breakdown, outlines their typical causes such as invalid requests, synchronized expirations, and hotspot spikes, and presents practical mitigation techniques including request validation, caching null values, Bloom filters, staggered expirations, high‑availability Redis setups, mutex locks, and random TTLs.
The article analyzes the repetitive maintenance of common fields like createTime and updateUser in SpringBoot CRUD services, presents six production‑tested strategies—including MyBatis‑Plus meta‑object handling, AOP with custom annotations, multi‑data‑source adaptation, distributed ID generation, caching, batch optimization, and audit logging—detailing implementations, pitfalls, and best‑practice recommendations that can cut code by 90% and boost development efficiency.
This article explains how to implement a plug‑and‑play development model in Spring Boot using Java SPI, custom configuration, and Spring Factories, providing step‑by‑step code examples, a multi‑module microservice case study, and practical guidance for creating extensible, decoupled applications.
This article walks through the challenges of synchronizing 50 million rows between disparate MySQL databases, explains why traditional mysqldump or file‑based methods fail, and then details how the open‑source DataX tool—its 3.0 framework, installation steps, job architecture, and JSON‑based configurations—enables fast full and incremental data transfers with concrete performance metrics.
This tutorial shows how to add OCR capabilities to a SpringBoot application using the Tess4j library, covering dependency setup, Tesseract engine initialization, RESTful endpoint implementation, training data choices, and practical tips for handling resources and deployment.
This article walks through five concrete implementations for per‑minute API call counting—fixed window, lazy sliding window, Spring AOP, Redis time‑series, and Micrometer + Prometheus—detailing their design, code, trade‑offs, benchmark results, memory usage, and real‑world deployment tips.
The article explains why scanning a 200 GB InnoDB table on a MySQL server with only 100 GB of memory does not cause an out‑of‑memory crash, detailing MySQL's row‑by‑row net buffer transmission, InnoDB buffer‑pool behavior, and the improved LRU algorithm that limits memory impact.
This article analyzes how to build a real‑time, billion‑user leaderboard for a game like Honor of Kings, explaining why traditional ORDER BY queries fail, why Redis sorted sets excel, and detailing sharding, hot‑key mitigation, memory optimization, and fault‑tolerant implementation techniques.
