We share common IT technologies (Java, Web, SQL, etc.) and practical applications of emerging software development techniques. New articles are posted daily. Follow IT Xianyu to stay ahead in tech. The IT Xianyu series is being regularly updated.
This article explains why the built‑in REST Client in IntelliJ IDEA can replace Postman by offering equivalent request features, environment handling, shared scripts, response assertions, and token management, all within a single development environment.
This article presents seventeen practical Python techniques—including list manipulation, string handling, dictionary operations, and chaining—that are simple to implement yet widely applicable, helping developers write cleaner, more concise, and more efficient code across various domains.
This article explains how MySQL's InnoDB engine guarantees ACID properties by describing the four components of ACID, the four isolation levels, lock granularity and types, the MVCC mechanism with version chains and read views, and the roles of undo, redo, and bin logs in ensuring atomicity, consistency, isolation, and durability.
This article demonstrates how to build a lightweight, plug‑and‑play flow‑orchestration system for microservices by installing Nacos with Docker, configuring SpringBoot services with Kafka and Nacos, and using dynamic Nacos listeners to adjust Kafka topics at runtime without redeployment.
This tutorial explains how to install Spring Boot CLI, demonstrates the project layout, creates a Hello World application using Groovy, shows how to use @Grab for dependencies, run tests, package the app into an executable JAR, and generate new projects with the init command.
This article explains the concept of configuration, enumerates various configuration sources such as hard‑coded values, project files, file‑system files, network‑based stores, JVM startup parameters and OS settings, and discusses their advantages, disadvantages, and suitable usage scenarios for developers.
This article introduces NanoID as a modern alternative to UUID, explains how to install and use it in JavaScript projects, compares performance, size, and security, discusses customization options and limitations, and suggests when to prefer NanoID for future development.
This article explains how to identify slow SQL statements, analyze execution plans with EXPLAIN, use profiling and tracing tools, and apply specific optimization techniques such as index tuning, query rewriting, and alternative storage solutions across a range of real‑world cases.
This article provides a comprehensive guide to relational database design with MySQL, covering ER modeling, BCNF and 3NF normalization, storage engine selection, character set and data type choices, and index design principles, illustrated through a student‑course selection example.
This article explains how to evolve a simple single‑server web application into a highly available, horizontally and vertically scalable system for billions of users by covering DNS, vertical and horizontal scaling, load balancing, database replication, sharding, denormalization, SQL/NoSQL choices, stateless design, caching, CDN and global deployment.
