The author describes how changing a SpringBoot controller annotation from @GetMapping to @PostMapping caused a silent 404 error, how a teammate quickly fixed it by disabling CSRF, and how a visual tool helped reveal the underlying filter-chain behavior.
This article explains how to create simple AOP aspects in Spring Boot 3, then dives into complex scenarios such as combining pointcut expressions, sharing pointcuts across aspects, programmatic pointcut composition, and controlling advice execution order, providing clear code examples for each case.
This article introduces three top‑tier authentication solutions—Clerk, Supabase Auth, and Better Auth—detailing their key features, supported strategies, customization options, and integration benefits, helping developers decide which framework best fits their user management and security needs.
After building sizable projects in Go, Zig, and Rust, the author compares their performance, safety, ecosystem, and developer experience, ultimately concluding that Rust’s ownership model and compile‑time guarantees make it the superior choice for backend engineers despite Go’s speed and Zig’s simplicity.
This guide explains how to install the Webman rate‑limiter plugin, configure its drivers (memory, APCu, Redis), and use annotation‑driven limits in PHP controllers, including custom keys, whitelist IPs, and manual limiter checks.
This guide explains what WeChat Mini Program subscription messages are, outlines common use cases, and provides a step‑by‑step implementation process—including template creation, backend push configuration, frontend subscription requests, and server‑side message sending with code examples.
This article presents Liteflow, a lightweight yet powerful rule engine for Java/Spring Boot, explaining its architecture, supported rule formats, component types, configuration, code examples, and a real‑world e‑commerce workflow, while also noting its high‑performance startup processing and monitoring capabilities.
To avoid performance degradation caused by simultaneous large‑scale data exports, this guide demonstrates building a fixed‑size FIFO export queue in Spring Boot, integrating EasyExcel for million‑row exports, handling asynchronous processing, and providing sample code for the queue, export service, and controller.
This article explains how Java's BigDecimal class preserves decimal precision by scaling numbers to long integers, detailing its internal fields, key methods, and step‑by‑step execution of an addition example to illustrate the underlying algorithm.
This tutorial walks through creating a simulated SMS verification system using Spring Boot, Redis, and scheduled tasks, covering requirements, dependency setup, controller and service implementation, rate limiting, code expiration, validation logic, and daily reset of usage counters.
PHP 8.4.1 introduces a suite of backend improvements—including property hooks, asymmetric visibility, deprecation attributes, a spec‑compliant DOM API, an object‑oriented BCMath API, and several new array_* functions—each illustrated with concise code examples and usage notes.
This article explains why Java's BigDecimal class ensures loss‑free precision in financial calculations by examining its internal fields, demonstrating usage with a test method, and walking through the add method's scaling logic and integer‑based computation.
This article explains PHP's is_file() function, demonstrates its usage with sample code, outlines important considerations, and summarizes how it can be applied to verify whether a given path points to a file.
This article explains the newly added os.Root type and os.OpenRoot function in Go 1.24, demonstrates how they restrict file operations to a specific directory, and shows how they prevent classic directory‑traversal exploits such as CVE‑2024‑3400.
The article examines five common rate‑limiting algorithms—Fixed Window, Sliding Window, Sliding Log, Leaky Bucket, and Token Bucket—detailing their principles, pros and cons, and providing complete C++ implementations to help developers choose the best approach for controlling traffic bursts and ensuring system stability.
This article details how a SpringBoot advertising platform service with startup times of 400‑500 seconds was analyzed and optimized through Actuator monitoring, log inspection, Tomcat TLD scan disabling, asynchronous HBase warm‑up, custom BeanPostProcessors, async JSF consumer initialization, Tomcat version tuning, and hardware upgrades, achieving roughly a 60% reduction in launch time.
This article explains the concept of layered architecture in Java backend projects, outlines five design dimensions, presents a nine‑layer SpringBoot module structure, and provides concrete code examples for each layer—including util, infrastructure, domain, service, integration, facade, client, controller, and boot—demonstrating how to achieve clean separation of concerns and maintainable code.
This article explains the PHP file_put_contents() function, detailing its syntax, parameters, return values, and providing multiple code examples for writing strings, appending data, handling arrays, and using callbacks to dynamically generate file content.
This article explains PHP’s is_callable() function, detailing its purpose, parameter options, and how to use it to verify whether functions or class methods are callable, accompanied by clear code examples demonstrating checks on a simple function and a class method.
This article explains how to use PHP's mysqli_query function to connect to a MySQL database, execute SELECT, INSERT, UPDATE, and DELETE statements, and process results, including a complete example code snippet demonstrating connection, query execution, result handling, and cleanup.
This course introduces the background and features of PHP, explains the role and inner workings of the PHP interpreter—including lexical analysis, parsing, and the virtual machine—and guides students through implementing interpreter modules in C, culminating in a hands‑on project to build a simple PHP interpreter.
This article analyzes the stability challenges faced by an e‑commerce inventory platform—including complex business flows, database hotspots, and high‑frequency calculations—and details a series of engineering solutions such as traffic splitting, gray‑release pipelines, Redis caching, consistency checks, throttling, and comprehensive monitoring to improve reliability and performance.
This tutorial demonstrates how to implement flexible, module‑aware operation logging in Spring Boot 3 by combining custom @Log annotations, AOP aspects, and Spring Expression Language (SpEL) to capture dynamic data such as usernames, product names, and order totals.
This article explains the limitations of traditional HTTP session handling, explores session sharing strategies for clustered environments, and demonstrates how to build a single sign‑on solution using CAS and OAuth2 concepts with complete Java code examples for filters, controllers, and login pages.
Microservices and Service‑Oriented Architecture (SOA) both aim to modularize systems, but they differ in design philosophy, technology heterogeneity, governance, and deployment, with microservices favoring fine‑grained, independent services, decentralized governance, and container‑based continuous delivery, while SOA relies on larger, centrally managed services via an ESB.
This article demonstrates how to create a reusable PHP function that searches a two‑dimensional array for a specific id and returns the value of a given key, such as the title, using a simple loop and conditional check.
This article compiles sixteen practical Redis use‑cases—from caching and distributed locks to rate limiting, bitmaps, shopping carts, timelines, queues, likes, tags, filtering, follow/fan relationships, and leaderboards—providing code snippets and command examples to help backend developers design scalable systems.
This article explains the fundamentals of socket programming in Python by demonstrating how to build a lightweight UDP-based chatroom, covering socket creation, common methods, and complete server‑client examples with code snippets for multi‑user communication.
This article presents a comprehensive design for securing third‑party APIs, covering permission segmentation, AK/SK generation, signature workflow and rules, anti‑replay mechanisms, token handling, detailed API endpoint specifications, and best‑practice security measures with illustrative Java code examples.
This article introduces a lightweight, extensible Java framework that uses custom annotations to translate relational data, dictionaries, collections, and nested objects, detailing its background, architecture, core annotation design, usage examples, advanced features, Spring Boot integration, ORM support, and provides the open‑source repository link.
This article explains how to retrieve a file’s last modification time in PHP using functions like filemtime(), stat(), and the DateTime class, and provides a practical example for detecting changes and notifying users.
This article explains how to use PHP's define() function to create constants, detailing its syntax, parameters, a practical example, and important considerations such as naming rules, case sensitivity, immutability, and typical naming conventions.
This article walks through a real‑world Java CPU‑usage issue, showing how top, thread ID conversion, and jstack were used to pinpoint a faulty loop in LoguUtil, then verifies the fix restores normal CPU consumption while emphasizing the importance of performance testing.
This article explains PHP’s built‑in floatval() function, its syntax, and provides multiple code examples showing how to convert integers, strings, booleans, and arrays to floating‑point numbers, while also noting conversion limitations such as non‑numeric strings returning zero.
This article examines how pagination queries on large MySQL tables become dramatically slower as the offset grows, presents real‑world performance measurements, and offers three practical optimization strategies—including selecting only primary keys, range‑based filtering, and using ElasticSearch—to keep query latency low.
This article explains the PHP fgetc() function, shows how to open files with fopen(), demonstrates reading characters from files and standard input using loops and switch statements, and provides complete code examples for practical use.
This article explains PHP’s is_numeric() function, detailing how it determines whether a variable is numeric, provides multiple code examples—including simple variable checks and form input validation—and discusses special cases such as decimal points and trailing symbols.
The article introduces Laravel's new context() helper, demonstrating its basic usage and a real‑world multi‑tenant example, showing how to add, retrieve, and default context values and simplify shared data handling throughout the request lifecycle.
This article explains PHP's urldecode() function, covering URL encoding concepts, the function's signature, practical encoding/decoding examples, limitations with non‑printable characters, and when to use rawurldecode() as an alternative.
This article introduces PHP's array_keys() function, explains its syntax and optional parameters, and provides three practical code examples demonstrating its use with indexed, associative, and multidimensional arrays, helping developers retrieve array keys efficiently.
This article explains what PHP constants are, how to define them with define() or const, showcases practical examples, outlines their benefits such as data consistency and global access, and provides best‑practice guidelines for using constants effectively in backend development.
This guide explains how Nginx processes regular expressions and location directives, detailing the syntax, common regex symbols, matching rules, priority hierarchy, and practical configuration examples to help you fine‑tune request routing on a single‑node server.
The article analyzes a mysterious production stall caused by a TCP communication bug where the D4 and D5 stages are merged, leading to a mis‑aligned length field that makes the server read an incorrect payload size, and presents two concrete fixes.
This article provides a step‑by‑step guide to building a Spring Boot starter that abstracts object storage services (OSS) via the Amazon S3 protocol, covering dependency selection, configuration properties, template interfaces, implementation, auto‑configuration, packaging, and testing for cloud‑native backend applications.
This article explains how PHP's tmpfile() function creates a unique temporary file that is automatically deleted when closed or when the script ends, and demonstrates its usage with example code for writing, reading, and cleaning up the file.
This article explains PHP 8.1 Fibers, describing their cooperative multitasking mechanism, how suspension and resumption affect the main script, why they do not provide true asynchronous execution, and how they can be combined with event loops for more efficient non‑blocking code in backend development.
This article explains how to design a QR‑code login flow, create the necessary database table, define the required APIs, and integrate front‑end JavaScript with a Spring Boot back‑end using WebSocket to notify the client of successful authentication.
This article explores the core functions of e‑commerce shopping carts and compares client‑side storage methods such as Cookies and LocalStorage with server‑side solutions like Redis and MySQL, offering guidance on choosing the appropriate approach based on business scale and reliability requirements.
This article examines why using Redis key‑space expiration notifications for delayed job execution is unreliable, compares common approaches such as message‑queue delayed delivery, RabbitMQ dead‑letter queues, time wheels, and Redisson DelayQueue, and provides practical recommendations for robust timeout handling in e‑commerce systems.
This article explains how to protect front‑end and back‑end communication in a Spring Boot application by encrypting request and response data using a hybrid AES and RSA scheme, custom request wrappers, filters, and AOP‑based response encryption, complete with code examples and implementation details.
This article outlines why PHP 8.4 is a substantial upgrade, highlighting enhanced object‑oriented programming, developer‑friendly attributes, new language constructs, performance improvements, and a host of new functions and library support that make it a compelling move for modern backend development.
This article explains PHP’s is_numeric() function, detailing how it determines whether a variable is numeric, providing multiple code examples—including simple variable checks, form input validation, and discussion of special cases like trailing decimal points—so beginners can effectively use it in their projects.
This article explains the PHP fgetc() function, shows how to open files with fopen(), demonstrates reading characters from a file and from STDIN using loops and switch statements, and provides complete code examples for each scenario.
This article explains the complementary roles of JWT and server‑side Session in user authentication and authorization, outlines why Session is needed for added security and lifecycle management, and provides Java code examples demonstrating their integrated usage.
This article explains critical pitfalls and best‑practice guidelines for employing Spring Event in Java backend applications, covering graceful shutdown requirements, event loss during startup, suitable business scenarios, reliability enhancements, retry mechanisms, idempotency, and the relationship between Spring Event and message queues.
This article explains the purpose and implementation of getters and setters in PHP, demonstrates their advantages for data validation and encapsulation, and provides comprehensive code examples showing how to combine them for secure and reliable object property management.
This article explains PHP's str_word_count() function, detailing its syntax, parameters, and providing multiple code examples that demonstrate counting words, retrieving word arrays, obtaining word positions, customizing ignored characters, and using regular expressions for word extraction.
This article explains the PHP is_file() function, its syntax, parameters, return values, and provides clear code examples for checking whether a path points to an existing regular file and how to differentiate it from directories using is_dir().
This article examines PHP 8.4's new Property Hooks feature, compares it with Laravel Eloquent's Mutators, provides implementation examples for both, and offers guidance on when to prefer each approach based on project requirements and performance considerations.
This guide explains how to add Ondřej Surý's repository, install PHP 8.4 alongside existing versions, handle deprecated features, configure web‑server integration, manage extensions, verify the installation, and safely remove older PHP packages on Ubuntu or Debian systems.
This article explains how to build a scalable, maintainable permission control framework in Java by defining custom annotations, designing relational database tables, and using Spring AOP to intercept method calls for organization‑level, personal, limit, and special‑role checks, while providing implementation details and best‑practice recommendations.
PHP 8.4 introduces property hooks, asymmetric visibility, new array functions, simplified object instantiation, explicit nullable types, and lazy objects, providing cleaner syntax, better control, and performance improvements for developers across skill levels.
This article examines common problems in Spring Boot controller implementations—excessive try‑catch blocks, inline validation, and business logic leakage—and demonstrates how to refactor them using @Valid, assertion utilities, and a global exception handler to achieve concise, maintainable backend code.
This article documents the diagnosis of slow SpringBoot startup in a large‑scale advertising platform and presents a series of optimizations—including actuator monitoring, Tomcat TLD scan disabling, HBase async warm‑up, custom BeanPostProcessor timing, asynchronous JSF consumer refer, Tomcat version tuning, and hardware migration—that together reduce launch time by about 60%.
This article explains the PHP glob() function, detailing its syntax, parameters, and various usage examples—including wildcard, brace expansion, and recursive matching—to help developers efficiently retrieve file paths matching specific patterns, while noting important considerations such as flags and empty results.
This article explains PHP's is_float() function, demonstrates its usage with simple and complex code examples, discusses its strict type checking behavior, and shows how it can be applied to mixed‑type data collections.
This article explains the Chain of Responsibility design pattern, shows why a naïve nested‑if implementation is problematic, and demonstrates step‑by‑step refactorings—including abstract handlers and a factory‑based configuration—to create clean, maintainable Java backend code.
A developer team debates whether to store monetary amounts as BigDecimal or long, discussing experience‑based preferences, past incidents, and asking the community for real‑world pitfalls of each approach.
The article examines common pain points of oversized Spring controllers, contrasts a verbose implementation with a concise version that leverages @Valid and assertion utilities, and provides step‑by‑step guidance on validation annotations, global exception handling, and best‑practice refactoring to improve readability and maintainability.
This article explains the PHP trim() function, detailing its default behavior of removing whitespace from both ends of a string, how to use the optional character mask to strip specific characters, and provides clear code examples with expected output for each case.
This article explains the PHP is_object function, its syntax, and demonstrates with code examples how to determine whether a variable is an object or not, highlighting the difference between objects and arrays and the importance of proper type checking in backend development.
This article provides a comprehensive overview of common HTTP request and response headers, explaining their purposes, typical usage, and example syntax, helping developers prepare for interviews and deepen their understanding of web communication fundamentals.
ThinkPHP 8.1, slated for release in November, brings extensive improvements over 8.0—including routing enhancements, validation upgrades, multi‑module support, new middleware controls, expanded cache options, refined exception handling, and compatibility with PHP 8.4—providing developers with a more robust and flexible backend framework.
This article explains PHP's array_unique() function, covering its definition, parameters, implementation, usage examples, and performance optimization techniques, while providing complete code snippets and practical guidance for developers, including discussion of alternative approaches such as array_flip and array_keys for faster deduplication.
This article explains the PHP is_file() function, showing how it determines file existence, the accepted path formats, important usage notes such as its inability to check directories, and provides practical code examples for common scenarios.
This article presents a comprehensive overview of payment system architecture, detailing core transaction and payment modules, service governance, data consistency, asynchronous processing, performance testing, and practical production practices for building a robust backend payment platform.
This article explains the motivations for creating a custom PHP framework—such as meeting specific needs, learning opportunities, long‑term maintenance, performance optimization, ease of use, and security—while also outlining the course chapters covering MVC, routing, error handling, namespaces, singleton pattern, configuration, and database operations.
This article explains the motivation, design choices, architecture, and core technical details of implementing the AMQP protocol on top of RocketMQ, including model mapping, proxy layer, LMQ queues, message flow, binary protocol handling, feature comparison, performance tuning, and future plans.
This tutorial demonstrates how to install Portainer, use it to deploy a Redis‑Sentinel cluster with master‑slave replication and custom bridge networking, test failover, and then integrate the Sentinel setup into a Spring Boot application with Lettuce connection pooling.
This article explores whether Node.js can handle millions of concurrent users, explains the core non‑blocking architecture, outlines challenges such as the single‑thread model and memory leaks, and provides practical scaling tactics like clustering, load balancing, caching, and database optimization.
This article presents ten widely applicable backend performance‑optimization strategies—including defensive validation, batch processing to eliminate N+1 queries, asynchronous execution, parallelism, caching, connection pooling, security hardening, compression, message‑queue decoupling, and design‑pattern reuse—each illustrated with Go code examples and practical case studies.
This article explains the concept of idempotency, identifies which HTTP operations are naturally idempotent, describes why idempotency is needed in scenarios like timeout retries, async callbacks and message queues, and provides a complete Spring Boot implementation using a custom annotation, Redis storage, AOP interception, token generation and example controllers.
This article demonstrates how to wrap the EasyExcel library in a Spring Boot + MyBatis‑Plus project, providing a unified component that simplifies Excel import and export through concise annotations, reusable service methods, and customizable converters while addressing common pitfalls such as date handling and template support.
This article explains PHP's str_replace function, detailing its syntax, demonstrating simple replacements, multiple replacements using arrays, and character deletions with code examples, while also noting additional options and linking to further PHP learning resources.
This course, designed for developers with basic front‑end experience, teaches how to combine the uniapp framework and ThinkPHP backend to build high‑performance, cross‑platform mobile applications, covering topics such as data modeling, token authentication, middleware, API design, pagination, and deployment.
Discover the 11 most popular open‑source projects that freelance developers rely on—from fast front‑end build tools like Vite and Tailwind CSS to back‑end frameworks such as Express, ORM Sequelize, real‑time Socket.IO, testing with Jest, code quality with ESLint and Prettier, and containerization with Docker—each with concise usage examples.
mica-mqtt is a simple, low-latency, high-performance open-source MQTT component built on Java AIO, supporting MQTT v3.1, v3.1.1, v5.0, WebSocket, HTTP API, client/server modes, clustering via Redis Stream, and easy integration with Spring Boot, Solon, and JFinal for diverse IoT and messaging scenarios.
This article explains the browser same‑origin policy, defines cross‑origin requests, details the CORS mechanism—including simple and non‑simple requests and their required HTTP headers—and provides practical Go examples using Gin middleware and Kubernetes to solve CORS issues.
In 2024 PHP has resurged thanks to dramatic performance gains, modern language features, a thriving Laravel ecosystem, robust hosting support, and extensive compatibility, making it a fast, reliable choice for building high‑traffic web applications once again.
PHP's rawurldecode() function decodes URL‑encoded strings—typically those produced by urlencode()—back to their original form, with syntax, usage examples, and a note on its difference from urldecode(), making it a handy tool for handling URLs in backend web development.
This article introduces Java enums, explains their definition, basic usage such as declaring, accessing, and iterating values, demonstrates advanced features like adding fields, implementing interfaces, using them in switch statements, and shows how enums can implement design patterns such as Singleton and Strategy.
The article recounts a developer’s mistake of entering an extra decimal place in a SQL update for daily interest rates, explains how the error escaped code review, testing and production validation, and shares practical lessons on precision handling, review processes, and operational safeguards.
This article explains PHP's in_array() function, covering its syntax, parameters, return values, and demonstrating its usage with basic, strict mode, and multidimensional array examples to help developers quickly determine element presence in arrays.
This guide explains how to design and build a privacy‑focused, view‑once image sharing system using Spring Boot, MySQL, Thymeleaf, and optional cloud storage, covering requirements analysis, architecture, environment setup, code implementation, security considerations, performance optimizations, testing, and deployment.
This article explains, step by step, how to estimate capacity, choose the appropriate garbage collector, size the young and old generations, configure stack memory, adjust object aging thresholds, and fine‑tune CMS or G1 settings so that a Java service handling one million daily logins can run reliably on an 8 GB node.
This article introduces AviatorScript, a lightweight high‑performance expression engine and scripting language for the JVM (including Android), outlines its core features, demonstrates basic expression evaluation, variable handling, built‑in and custom functions, and shows how to run full scripts with code examples.
This article explains PHP's str_replace function, its syntax, and demonstrates three examples—simple replacement, multiple replacements using arrays, and character deletion—showing how to modify strings efficiently in backend development, including sample code and expected output for each case.
This article explains the read‑write lock separation design pattern, its principles, suitable scenarios such as high‑concurrency inventory queries, and provides a complete Java implementation with ReentrantReadWriteLock, including code samples, testing, performance benefits, and a discussion of its advantages and limitations.
This article explains the Chain of Responsibility design pattern, demonstrates its application in a product creation workflow with concrete Java code, shows how to configure and assemble handlers dynamically using Spring, and discusses the pattern's advantages, drawbacks, and testing scenarios.
This article explains how to replace repetitive try‑catch blocks in Java backend development with a unified exception handling approach using Spring's @ControllerAdvice, custom Assert utilities, and enum‑based error codes, providing cleaner code, consistent error responses, and easy internationalization.
