Java backend, microservices, distributed systems, containerized programming, and more.
This article explains how to eliminate manual logging of user and order identifiers in Java e‑commerce services by using Log4j2 placeholders, ThreadLocal, MDC, a custom @UserLog annotation, and Spring AOP to automatically enrich log messages with these contextual fields.
Discover how treating the literal string "null" as a legitimate username can cause hidden bugs across frontend validation, backend logic, database integrity, and security, and learn practical code snippets and defensive strategies to detect and prevent these pitfalls.
This tutorial walks through integrating SpringDoc into a Spring Boot project, covering why it replaces SpringFox, how to configure it with minimal settings, add API annotations, set up grouped documentation, and handle static resources and Spring Security for full Swagger UI access.
This article explains how to handle distributed consistency when a business operation writes to MySQL and calls external systems, using a financial reimbursement example to illustrate risks, analyzes the root cause, and presents a step‑by‑step solution that splits the large transaction into small, retryable units with code snippets and Spring optimization.
When a core order table with tens of millions of rows needs a new business field, directly running ALTER TABLE can lock the table and disrupt services, so this article explores master‑slave switching, online DDL tools, extension tables, JSON fields, and clever reuse of existing redundant columns to achieve the change safely and efficiently.
This article explains why dynamic configuration refresh is needed in Spring Boot, describes the core principles of @RefreshScope, provides step‑by‑step implementation code, and shares best practices and troubleshooting tips for zero‑downtime configuration updates in production environments.
This article compares MySQL and PostgreSQL by outlining their histories, architecture differences, benchmark results for SELECT, INSERT, and UPDATE operations, and discusses which scenarios each database best fits, helping readers decide which system to adopt for their projects.
This article explains why and how to run Windows environments in Docker containers, compares the two container modes, lists supported Windows images, provides a quick Hello World example, and highlights the main limitations you should consider before adopting Windows containers.
This article demystifies authentication concepts—Cookie, Session, Token, JWT, and OAuth2—using clear analogies, explains their inner workings, advantages, drawbacks, and provides practical guidance on when to choose each mechanism for modern web applications.
This article compiles essential Spring and Java utility methods—including assertion checks, object and collection handling, file I/O, resource management, and reflection/AOP tools—providing concise code examples and usage guidelines to help developers avoid redundant code and write cleaner, more reliable applications.
