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 tutorial provides step‑by‑step instructions for installing Hadoop 3.1.1, Homebrew, Hive, and configuring MySQL as Hive's metastore on macOS, including environment variable setup, hive‑site.xml configuration, MySQL connector placement, schema initialization, and verification commands.
The article explains that Java's Integer caching for values between -128 and 127 causes small integer objects to be shared, making == true for 100, whereas larger integers like 1000 are distinct objects, so == returns false, and it demonstrates this behavior with code and reflection examples.
This article demonstrates how to enable browser-based preview of Word, Excel, and PowerPoint files in Java by converting them to PDF streams with Apache OpenOffice and JODConverter, covering installation, Maven setup, utility code, service logic, and controller exposure.
This guide explains why and how to migrate an HTTP website to HTTPS, covering the differences between the protocols, options for obtaining SSL certificates, step‑by‑step installation of the acme.sh script, generating, installing, and automatically renewing certificates using both HTTP and DNS validation methods.
This article explains how to inspect and clear Linux memory buffers, details the information shown by the free command, and provides a comprehensive overview of SQL join types, their performance impact, and optimization techniques such as indexing, join buffer tuning, and algorithm choices.
This article introduces essential Redis operational tools, covering the INFO command for monitoring, Prometheus‑based redis‑exporter visualization, the Redis‑shake data migration utility, Redis‑full‑check consistency verification, and the CacheCloud platform for comprehensive cluster management.
This article explains the principles, features, and implementation details of carrier‑based one‑click login and mobile number verification services offered by China Mobile, China Telecom, and China Unicom, highlighting SDK usage, network requirements, caching, and security considerations.
This tutorial walks through installing Nginx from source, setting up upstream reverse‑proxy groups, configuring various load‑balancing methods (weight, IP hash, URL hash, least connections), enabling SSL, deploying Keepalived for failover, and building an LVS‑DR high‑availability cluster with detailed command‑line examples.
This article explains how to use Maven profiles and the maven‑assembly‑plugin to create environment‑specific zip packages for a Spring Boot application and provides a reusable shell script (shenniu_publish.sh) for extracting, starting, stopping, and managing the deployed JAR on Linux.
This guide explains step‑by‑step how to set up class and method comment templates in IntelliJ IDEA, including creating file and live templates, configuring parameters, adding Groovy scripts for @param and @return generation, and verifying the generated Javadoc comments for Java files.
