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This article explains how to retrieve a client’s real IP behind proxies, choose the appropriate forwarding header, and use the open‑source ip2region library to map the IP to a geographic location, with complete Java and Spring Boot code examples.
The article explains the concept of idempotency, outlines common duplicate‑submission scenarios such as form resubmission, malicious voting, client retries, and message re‑consumption, and details three practical implementation methods—database constraints, token‑based middleware, and state‑machine logic—complete with code examples and trade‑off considerations.
This article explains Canal's background, core functions, deployment steps, and component architecture, then shows how to integrate it with Spring Boot to monitor MySQL binlog events and keep Redis cache synchronized with database changes, while also covering Canal‑admin management and limitations.
This article explains Kafka’s architecture in depth, covering components such as producers, consumers, topics, partitions, replication, Zookeeper coordination, the Controller’s election and responsibilities, state machines, and the NIO‑based network model, using clear diagrams and analogies.
The article analyzes why massive tables become a bottleneck in Spring Boot systems, outlines the drawbacks of sharding, and presents a layered solution—data archiving, read‑write separation with caching, heterogeneous source synchronization via Elasticsearch and Canal, and selective sharding—to enable high‑performance real‑time search.
The article explains why rate limiting is essential for high‑traffic Spring Boot services, compares counter, sliding‑window, token‑bucket and leaky‑bucket algorithms, demonstrates implementations with plain Java, Guava RateLimiter, AOP, and distributed approaches using Redis‑Lua and Nginx‑Lua, and provides practical configuration examples.
This article analyzes frequent scenarios where Spring's @Transactional annotation fails in Spring Boot projects—such as self-invocation, swallowed exceptions, misconfigured rollback rules, non‑public methods, wrong propagation settings, and long‑running transactions—and provides concrete fixes to prevent data inconsistency and performance issues.
This article explains how to build a three‑layer cache architecture for Spring Boot by integrating Redis as a distributed cache with Caffeine as a local cache, covering configuration, custom CacheManager implementation, message‑driven synchronization, and practical usage examples.
This article explains why transaction control is essential for database‑backed applications, compares native JDBC/MyBatis handling with Spring's unified approach, details the core transaction APIs, and walks through the AOP‑based mechanism—including @EnableTransactionManagement, proxy generation, and CGLIB interception—that automatically opens, commits, and rolls back transactions at runtime.
This article explains how Spring AOP integrates AspectJ using CGLIB or JDK dynamic proxies, walks through a complete logging aspect example, and details the internal registration, proxy creation, and invocation processes that enable cross‑cutting concerns without modifying business code.
