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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.
The article lists the most frequent Java OutOfMemoryError variants, explains their root causes and typical scenarios, provides concrete code examples that trigger each error, and offers practical troubleshooting steps and JVM tuning recommendations for interview preparation.
The article explains how SpringBoot’s asynchronous request handling—using Callable, WebAsyncTask, and DeferredResult with a custom thread pool—can boost API throughput up to ten times compared to synchronous processing, while detailing the internal flow, configuration steps, and scenarios where async is beneficial.
The article explains why clean, well‑structured code matters for team productivity, covering naming, class design, function design, SOLID principles, testing practices such as TDD and the FIRST rule, and shows how tools like SonarLint can help maintain code quality.
This article introduces Aviator, a lightweight JVM‑based expression engine, explains its features and limitations, and demonstrates how to integrate it with Spring Boot and AOP to replace traditional if‑else validation logic using custom annotations and script files.
When a MySQL order table with 20 million rows is paginated using a large OFFSET, query latency can explode from seconds to minutes, but applying six concrete techniques—cursor pagination, deferred join, covering index, table partitioning, precomputed pages, and Elasticsearch integration—can shrink response time to a few hundred milliseconds.
The rapid rise of DeepSeek’s code‑generation AI has led to significant layoffs among programmers, prompting a shift in career strategy toward embracing AI tools, focusing on non‑automatable skills, and continuous learning to stay relevant in the evolving software industry.
