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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.
This article explains why tasks submitted with ExecutorService.submit hide exceptions while execute prints them, demonstrates how Future.get() can retrieve hidden errors, and presents three practical solutions—inline try‑catch, a custom ThreadFactory with UncaughtExceptionHandler, and overriding afterExecute—to reliably handle thread‑pool exceptions in Java.
The article recounts a production incident caused by improper use of Spring Event, explains why graceful shutdown, correct startup timing, suitable business scenarios, and reliability measures such as retries and idempotency are essential, and presents six concrete best‑practice recommendations to prevent similar failures.
ByteDance and Kuaishou have launched an “anti‑jargon” campaign, posting restroom cartoons that urge employees to abandon buzzwords like “赋能” and “抓手,” arguing that such jargon hampers clear communication, reduces efficiency, and fuels overtime, while also serving as a status symbol within the tech industry.
The article explains how Java's BigDecimal class avoids precision loss by scaling numbers into integer representations, detailing its internal fields, the add method's branching logic, and a concrete test that demonstrates exact decimal addition for financial values.
The article compares four techniques—manual ThreadLocal copying, TaskDecorator, InheritableThreadLocal, and Alibaba's TransmittableThreadLocal—for passing user context and other data from parent to child threads in Spring Boot async execution, recommending the TaskDecorator and TransmittableThreadLocal approaches for production use.
The article presents a comprehensive design for third‑party APIs that protects against data tampering, replay attacks, and unauthorized access by using AK/SK key pairs, timestamp and nonce signatures, TLS encryption, fine‑grained permission models, rate limiting, idempotency handling, versioning, standardized response formats, and detailed implementation examples in Java.
The article explains how to troubleshoot extreme CPU usage in MySQL and Java processes, detailing step‑by‑step diagnostics with top, show processlist, jstack, and practical fixes such as adding missing indexes, disabling slow logs, using caches, and correcting busy‑loop code to bring CPU consumption back to normal levels.
