Freaks City

Spring Boot REST API Implemantation Project Configuration Spring Setup The project is initialized using Spring Initializr at https://start.spring.io/. The following properties are configured in the application.properties file: spring.datasource.url=jdbc:mysql://localhost:3306/personnel_directory spring.datasource.username=admin spring.datasourc ...

When working with MyBatis or MyBatis-Plus in Spring Boot applications, encountering "Invalid bound statement (not found)" exceptions typically indicates that mapper interfaces cannot locate their corresponding XML mapping files. This guide outlines common misconfigurations and their solutions. Mapper Location Configuration The primary ...

Exception management is a critical aspect of web applications, requiring attention on both client and server sides. For robust systems, implementing exception handling at both ends is recommended. This article focuses specifically on managing HTTP request exceptions on the server side using Spring's Web MVC framework. Common Exception Types Whe ...

Transitioning from Session-Based to Stateless Authentication Traditional HTTP sessions maintain user state directly on the server. During authentication, the server creates a session object, persists it in memory or a shared cache, and returns a session identifier embedded in a client-side cookie. Every subsequent request automatically attaches ...

Backend Development Framework Architecture Overview: Client sends HTTP request to Controller layer Controller receives the request and passes data to Service layer Service layer handles business logic, may interact with DAO layer for database operations or Client layer for remote service calls DAO layer executes database operations and returns ...

Internal Configuration Resolution Order File-name precedence bootstrap.yml (or bootstrap.properties) is processed before any application.* file. application.yml (or application.properties) is processed next. Directory precedence (highest → lowest) ./config/ – a config folder in the project root ./ – the project root itself classpath:/config/ ...

When tasked with enriching a dataset of IP addresses with geographic metadata—such as country, province, and city—the priority is rapid, reliable execution. This scenario involved processing several hundred IP records stored in a Excel file, converting them to CSV for simplicity, then calling an external geolocation API to append loccation deta ...

Database connection pooling is a foundational optimization in modern Java applications, especially within Spring Boot ecosystems. Misconfigurations or misunderstandings of pool behavior frequently lead to subtle production issues — such as stale connections, timeouts, or resource exhaustion — even among seasoned developers. Why Connection Pools ...

Project Dependencies To begin, configure the pom.xml file with the necessary dependencies for Spring Boot, MongoDB integration, and Lombok to reduce boilerplate code. <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0"> <modelVersion>4.0.0</modelVersion ...

User Table Structure The original table structure is designed as follows. Due to the large user base, database sharding becomes necessary. Sharding Strategy Design Based on the system design assumptions, the 12306 system needs to support approximately 1 billion registered users, with roughly 10 million new users annually. Before implementing da ...