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The article walks through six concrete rate‑limiting methods—fixed window, sliding window, leaky bucket, token bucket (Guava RateLimiter), Sentinel middleware, and Spring Cloud Gateway—showing Java implementations, test results, advantages, drawbacks, and how they fit into microservice architectures.
The article explains how to solve interleaved multi‑thread logs in micro‑services by adding a X‑App‑Trace‑Id header, extracting it in a TraceIdFilter, storing it in SLF4J MDC, propagating it through Feign, adapting it for child threads, and finally integrating SkyWalking to print both application and SkyWalking trace IDs in Logback.
This comprehensive tutorial walks through Alibaba Sentinel's core concepts, installation, dashboard setup, microservice integration, flow‑control configurations, degradation strategies, hotspot parameter limiting, system‑adaptive rules, custom block handlers, whitelist/blacklist policies, rule persistence with Nacos, and cluster flow control for resilient Java backend services.
The article explains what a dynamic thread pool is, why static pools are problematic, how to modify core parameters such as corePoolSize, maximumPoolSize, and workQueue at runtime, and provides code examples for monitoring, exposing metrics via Spring Boot Actuator, and integrating with Prometheus‑Grafana, while also listing open‑source implementations like Hippo4j and Dynamic TP.
This article analyses thirteen common mistakes that cause Spring's @Transactional annotation to be ineffective or not roll back, covering unnecessary usage, private/final/static methods, self‑invocation, wrong propagation settings, async threads, unmanaged beans, exception handling and more, with concrete code demos and solutions.
This article presents ten practical MyBatis dynamic‑SQL techniques—including foreach, if, choose, selectKey, trim, and sql fragments—explaining their attributes, common pitfalls, and providing complete Java mapper and XML examples that help reduce boilerplate and avoid errors.
The article walks through MySQL’s query execution flow, shows how to profile slow statements, explains index‑related pitfalls, connection‑pool limits, and InnoDB buffer‑pool sizing, and provides concrete commands and examples to diagnose and speed up sluggish queries.
The article explains why modifying a HashMap—by removing, adding, or putting entries—while iterating with a Java foreach loop causes a ConcurrentModificationException, demonstrates the underlying bytecode transformation, and shows how to safely perform such operations using an Iterator.
The article analyzes why Kafka messages are duplicated on both producer and consumer sides, explains at‑most‑once, at‑least‑once, and exactly‑once delivery semantics, and walks through three concrete remedies—idempotent producers, transactions, and consumer‑side deduplication—backed by configuration details, code samples, and practical deployment steps.
This article walks through eleven practical methods—such as adding proper indexes, optimizing SQL, parallelizing remote calls, eliminating duplicate queries, using async processing, shrinking transaction scope, refining lock granularity, applying pagination, leveraging caching layers, and employing sharding and monitoring tools—to dramatically improve backend interface performance.
