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Redis implements an approximate LRU using random sampling and timestamps, while classic LRU relies on exact access order; the article explains both LRU and LFU fundamentals, their Java implementations, Redis-specific variants, trade‑offs, use‑case recommendations, and configuration tips for selecting the optimal eviction policy.
This article compares Single Sign‑On (SSO) and OAuth2.0, detailing their conceptual distinctions, token‑based workflows, implementation frameworks like CAS, the four OAuth2.0 grant types, and how each can be used to achieve seamless authentication across applications.
The article walks through a year‑long investigation of a 404 error that appears after updating Nacos dynamic routing in Spring Cloud Gateway 3.0.1, explains how stale weight caches cause the failure, and presents a custom event‑listener solution that synchronizes the gateway's weight cache with the latest Nacos configuration.
When a core MySQL order table reaches tens of millions of rows, adding a new column can lock the table and disrupt services, so the article walks through master‑slave switching, online DDL tools, log‑based workarounds, extension tables, JSON fields, and a final redundant‑field trick to achieve the change safely.
This article explains the Chain of Responsibility pattern, shows how to use it for multi‑stage validation and workflow scenarios, walks through a product‑creation example with concrete handlers, configuration via JSON, Spring bean injection, recursive chain assembly, and a reimbursement‑approval workflow, complete with runnable test cases.
The article compares token bucket and leaky bucket rate‑limiting algorithms, explains their core principles, advantages, and suitable scenarios, and provides complete Java implementations with test code and interview tips for choosing the right approach.
This article presents a comprehensive, step‑by‑step analysis of a high‑throughput, asynchronous OCR pipeline built with Spring Boot and Tesseract, covering system architecture, thread‑pool tuning, custom invoice‑specific model training, multi‑engine fusion, structured data extraction, performance optimizations, GPU acceleration, Kubernetes deployment, monitoring, security compliance, chaos testing, and future evolution plans.
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.
