An ordinary programmer sharing tech and life.
The article explains how HashMap can enter an infinite loop, lose data, or corrupt entries when accessed concurrently, illustrates the root causes with JDK 1.7 and 1.8 source code, compares alternative thread‑safe maps, and shows how to answer this classic interview question.
The article reviews the end‑to‑end online lending process involving platforms, operators, fund providers, local banks and the central bank, discusses the technical hurdles of maintaining a legacy JSP system with closed‑source components, and reflects on the strategic importance of the platform ecosystem.
This article explains Retrieval‑Augmented Generation (RAG), describing its definition, why it complements large language models, the end‑to‑end workflow, its four core components—embedding, vector database, retriever, generator—and the value it adds by providing up‑to‑date knowledge and reducing model hallucinations.
The article reviews Andrew Ng’s ‘AI for Everyone’ course, explaining AI bias with a facial‑recognition example and mitigation tips, describing adversarial attacks and defenses, outlining harmful AI uses such as deepfakes and privacy threats, and discussing McKinsey’s job‑displacement and creation forecasts alongside AI‑assisted programming tools.
This article introduces the fundamentals of artificial intelligence, distinguishing ANI and AGI, explains machine learning as a core AI branch, describes data and data science, and clarifies the relationship between neural networks and deep learning, using simple examples and visual diagrams for beginners.
The article defines high concurrency, explains how to locate bottlenecks and understand user traffic patterns, then outlines practical measures such as distributed architecture, clustering, caching, asynchronous queues, rate limiting, database tuning, preloading, and fault‑tolerant monitoring to build robust high‑throughput systems.
This guide explains how to troubleshoot common online Java problems—including high CPU, OutOfMemoryError, disk I/O, and network latency—by using tools such as top, jps, jstack, jmap, MAT, df, and ping to pinpoint root causes like infinite loops, memory leaks, lock contention, and resource exhaustion.
