This article explains PHP's array_intersect() function, covering its syntax, required and optional parameters, return value, and provides three detailed code examples that demonstrate how to extract common elements from multiple arrays.
This guide walks through creating a Spring Boot 3.3.3 microservice permission framework with OAuth2, covering technology stack, core features, project structure, step‑by‑step service startup, token acquisition, API calls, and provides the complete source repository for hands‑on experimentation.
This guide explains how to prepare a clean, well‑documented enterprise code repository, outlines upload restrictions, annotation standards, naming conventions, and step‑by‑step usage of the Tongyi Lingma IDE plugin for both backend and frontend development scenarios, plus troubleshooting tips.
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, while also offering tips for combining it with other file functions.
This article explains PHP's is_callable() function, its parameters, and demonstrates its use with code examples for checking the callability of both functions and class methods, highlighting how it improves code robustness and maintainability.
This article explains the purpose and proper use of PHP's final keyword for classes and methods, illustrating when and how to apply it with clear code examples to enhance code stability, security, and maintainability in object‑oriented development.
This article introduces Python concurrency models—including threading, multiprocessing, and asyncio—provides step‑by‑step Flask web application examples, demonstrates SQLite database operations, and covers essential Git commands for version control, all with complete code snippets for practical learning.
This article walks through why real payment integration matters for C‑end projects and resumes, introduces the Blue Rabbit personal‑signing platform, details the step‑by‑step application, verification, fee payment, merchant activation, and provides Java SDK design patterns and code samples for integrating the API.
The article explains how using a database‑backed persistence layer for Java thread‑pool tasks prevents data loss during service downtime by storing tasks before submission, tracking status and retries, and employing idempotent processing with configurable pool sizes and scheduled reprocessing of failed or pending jobs.
The article outlines Ctrip Hotel's transition from a monolithic BFF model to a multi‑endpoint "one‑code‑many‑ends" architecture using NestJS, introduces a cloud‑function platform for improved performance and operational efficiency, and describes a dynamic gateway layer that further enhances front‑end flexibility across multiple client types.
This article walks through the challenges of setting up a Java backend environment, demonstrates how to create a Spring Boot project, explains version compatibility between Spring Cloud, Spring Boot, and Kafka, and provides reusable code snippets for exception handling, logging, CORS, Swagger, and response wrapping, along with recommended tools.
Redis Streams offer a memory‑efficient, easy‑to‑use message queue that matches many Kafka features, making it a practical alternative for projects that cannot afford the overhead of deploying a full‑blown Kafka infrastructure.
This article explains the most commonly used Spring Boot annotations—including @SpringBootApplication, @RestController, @RequestMapping, @Autowired, @Value, @Component, @Service, @Repository, and @Configuration—providing clear descriptions and practical code examples for each.
This tutorial explains how to perform partial updates of RESTful resources using the HTTP PATCH method and JSON Patch format in Spring Boot 3.2.5, covering all RFC‑6902 operations with code examples and a complete working controller implementation.
This guide explains how to integrate the mybatis-plus-generator-ui library into a Spring Boot project, configure database connections, launch the web UI, and use its customizable templates and naming converters to generate Entity, Mapper, Service, and Controller classes for multiple databases with a single click.
This article introduces the open‑source XXL-Job distributed task scheduling framework, explains its architecture and communication design, and provides a step‑by‑step hands‑on tutorial covering server deployment, executor configuration, task development (annotation, API, sharding), execution, and log inspection, with code examples and screenshots.
This article presents fourteen practical Java backend optimization techniques—including configuration‑file management, Lombok’s @RequiredArgsConstructor, modular code design, exception handling, reducing DB queries, avoiding null returns, minimizing if‑else, slimming controllers, IDE shortcuts, source‑code reading, design patterns, and efficient collections—each illustrated with clear code examples.
This article explains how to use PHP's filemtime function to obtain a file's last modification timestamp, demonstrates converting the timestamp to a readable date with date(), and provides code examples for retrieving modification times of a single file as well as multiple files.
This article provides an in‑depth overview of the WebSocket protocol, covering its fundamentals, advantages, lifecycle, message formats, Java API usage, Spring Boot integration, performance considerations, and future development directions, complete with practical code examples for both server and client sides.
This guide introduces the Python RQ library, shows how to install it with Redis, and provides multiple code examples covering queue creation, task execution, priority handling, timeouts, batch processing, scheduling, retries, and status tracking for building robust asynchronous back‑end systems.
The article reflects on the difficulties of turning abstract design concepts such as GOF patterns and DDD into practical, reusable middle‑platform services for an e‑commerce business, discussing when to abstract, the trade‑offs between thin and thick services, and how to balance efficiency with evolving business needs.
This article explains how to implement unified data desensitization in Java Spring Boot applications by creating custom annotations, enums, serializers, and utility methods that automatically mask personal information during JSON serialization, complete with code examples and test results.
This article explains why Spring Cloud prefers HTTP over RPC for remote calls, detailing the underlying Tomcat-based web service, the differences between HTTP and RPC protocols, their advantages and disadvantages, and provides guidance on choosing the appropriate approach for microservice architectures.
This guide explains how to integrate the Logbook library into Spring Boot applications to capture detailed HTTP request and response logs, covering dependency setup, configuration options, output formats, Logback file logging, custom sinks, and RestTemplate interception for comprehensive monitoring and debugging.
This article explains how to implement an online‑user counter using Redis sorted sets by detailing the four essential ZSET commands, fingerprint‑based user identification, Java and JavaScript code examples, and scheduled cleanup for accurate real‑time statistics.
This article explains how to track online users using Redis sorted sets by describing the core ZSET commands (zadd, zrangeByScore, zremrangeByScore, zrem), showing code examples for adding, querying, and cleaning up user sessions, and discussing fingerprint-based identification methods.
This article explains how the PHP array_chunk() function can split a large array into smaller chunks of a specified size, describes its parameters, and provides code examples showing both default behavior and key‑preserving splits.
Learn how to create and register custom type converters for Spring Boot @ConfigurationProperties, enabling seamless binding of complex objects from property files using @ConfigurationPropertiesBinding and BeanFactoryPostProcessor techniques, including code examples, configuration snippets, and two registration approaches for practical implementation.
This article reviews the most popular Java frameworks for 2024, explaining their purpose, key features, and how they help developers build scalable, secure, and efficient web applications across various industries.
This article compiles practical advice for Java developers feeling out‑of‑practice, covering migration to JDK 21, Spring Boot 3.2 observability, new language features, community resources, and strategies to boost confidence and stay current with the evolving Java ecosystem.
This article compiles a series of technical interview questions and answers covering C++ and Go language differences, thread communication methods on Linux and Windows, stack versus heap memory, orphan processes, read‑write locks, Go goroutine concurrency, TCP three‑way handshake, and a sample SQL query for gender‑based grouping.
The article details how a production Spring Boot system consumed excessive memory due to default JVM heap settings, explains the underlying JVM defaults, demonstrates diagnostic commands, and provides practical recommendations for configuring JVM parameters and monitoring memory usage to prevent similar issues.
This article provides a concise yet comprehensive guide to the most common SpringBoot annotations—including @SpringBootApplication, @EnableAutoConfiguration, @ComponentScan, @Service, @Repository, @Component, @RestController, @Bean, @ResponseBody, and @Autowired—explaining their purpose, composition, and practical code examples for building robust Java backend applications.
This article introduces the Redis in‑memory database, highlights the new "Redis Mastery" book that blends theory with practical examples, and explains core concepts such as SDS string structures, RDB/AOF persistence, master‑slave replication, and Sentinel high‑availability mechanisms.
This article explains Java thread pools, their advantages, internal mechanics, common pitfalls such as oversized queues, excessive threads, and data loss on crashes, and presents a persistence‑based solution using database‑stored tasks and scheduled retries to ensure no data is lost when services go down.
The article introduces mybatis-mate, an enterprise‑grade MyBatis module that supports sharding, multi‑datasource, data auditing, field encryption, sensitive‑data masking, automatic DDL maintenance, performance logging, and fine‑grained data‑scope control, providing code examples and configuration guidelines for Spring Boot projects.
This article walks through a Python web‑scraping project that fetches skin images, names, and prices from Honor of Kings, covering project background, required tools, site analysis, code implementation, data processing, and legal considerations.
This article explains traditional session mechanisms, challenges in clustered environments, and presents solutions such as session replication and centralized storage, then details the design and implementation of a CAS-based Single Sign-On system in Java, including code for user forms, controllers, filters, and configuration.
The article chronicles the time wheel algorithm from its 1997 origins, explains simple, round‑based, and hierarchical wheel designs, compares them to queue timers, details Dubbo’s HashedWheelTimer implementation, and shows how combining the wheel with a delay‑message queue can dramatically improve service scalability and efficiency.
This article explains how to use the Activiti workflow engine to design a multi‑level leave‑approval process, covering BPMN diagram creation, Spring Boot configuration, deployment, Java code for starting instances, task handling, database schema, API overview, and tips for extending the workflow without additional code.
This article provides a detailed tutorial on Maven, covering repository configuration, basic project structure, dependency management, module inheritance, unified version control, and common build plugins such as jar, assembly, and shade, with practical XML examples and code snippets for Java backend projects.
This article thoroughly examines the Gin Go web framework, focusing on its compressed radix tree routing mechanism, middleware handling, request lifecycle, and performance‑optimizing techniques, providing code examples and best‑practice recommendations for building high‑throughput backend services.
This article explains the concepts of role‑based access control (RBAC), compares RBAC models, shows how to configure permissions and user groups, and provides step‑by‑step code examples for integrating Spring Security with JWT, JSON login, password encryption and database authentication in Java backend applications.
Lock4j is a Java distributed lock library supporting Spring AOP, RedisTemplate, Redisson, and Zookeeper, offering simple usage, configurable properties, annotation-driven locking, custom executors, key generators, and failure strategies, with detailed setup, code examples, and advanced customization instructions.
This guide outlines a structured way to answer interview questions about thread pool principles, covering key parameters, execution flow, rejection policies, illustrative analogies, and common pitfalls to demonstrate deep understanding.
This article explains how Go's net/http package leverages function types combined with interfaces—particularly the Handler and HandlerFunc types—to create concise, flexible HTTP servers, reducing boilerplate, improving code reuse and testability, and demonstrates practical examples and underlying implementations.
This article introduces the ArthasHotSwap plugin, explains why hot‑updating a few Java classes in a test environment can save minutes compared to full redeployment, and provides step‑by‑step instructions—including downloading, compiling, uploading bytecode to OSS, and applying the changes on the server—complete with code snippets and screenshots.
This article introduces the ten most influential PHP 2024 updates—including readonly properties, enums, match expressions, constructor property promotion, named arguments, nullsafe operator, union types, string-key unpacking, JSON_THROW_ON_ERROR, and JIT compilation—explaining each feature with clear examples to boost coding efficiency.
This article demonstrates ten essential Python string manipulation techniques—including concatenation, splitting, searching, replacement, case conversion, slicing, formatting, whitespace trimming, list conversion, and URL encoding/decoding—each illustrated with clear code examples and expected output for practical API development.
This article provides a comprehensive overview of SpringBoot’s most commonly used annotations, covering MVC, bean, JPA, configuration, exception handling, and testing annotations, complete with clear explanations and practical code examples to help developers avoid pitfalls and write cleaner code.
This guide walks you through why Java remains vital, explains what Spring Boot is, outlines its core features, and provides a detailed learning roadmap covering Java fundamentals, Spring core concepts, web development, AOP, microservices, databases, security, DevOps tools, and deployment strategies for building robust enterprise applications.
This article presents a series of Python requests code snippets demonstrating how to upload and download files, compare contents, process CSV and JSON payloads, verify file size, name, MD5 checksum, MIME type, and handle multiple file uploads in typical backend API scenarios.
This article explains PHP's is_numeric() function, detailing its purpose, usage, return values, and special cases, and provides multiple code examples—including basic numeric checks, form input validation, and edge-case behaviors—to help beginner developers correctly determine whether variables are numeric.
This article introduces AviatorScript, a high‑performance, lightweight JVM‑based scripting language, covering its origins, key features, quick‑start setup, core syntax for numbers, strings, booleans, control flow, functions, and real‑world use cases such as client version control, marketing rules, and order risk management.
This article analyzes the challenges of real-time, reliability, and message ordering in a customer service instant messaging system and presents solutions such as WebSocket adoption, ACK-based reliability, heartbeat mechanisms, and a structured message protocol to ensure efficient and stable communication.
On his first day the new Java backend developer discovered duplicated internal and external configuration files causing NullPointerExceptions, hard‑coded role strings, mixed System.out and logger calls, missing manager review leading to DB mismatches, arbitrary production database edits, and Maven pom‑type dependency errors, prompting a shift to unified application.yml settings, JVM‑specified config locations, consistent logging, and stricter coding standards.
This article explains PHP's str_word_count() function, detailing its syntax, parameters, optional character list, and provides multiple code examples demonstrating how to count words, retrieve word arrays, obtain word positions, customize ignored characters, and use regular expressions for word matching.
This article explains the PHP is_file() function, its syntax, parameters, return values, and provides clear code examples showing how to determine whether a given path points to an existing regular file and how to differentiate it from directories or special files.
This article explains how Lombok's @RequiredArgsConstructor can replace repetitive @Autowired field injections in Spring services by generating a constructor for final fields, demonstrates the underlying annotation‑processing mechanism, and provides practical code examples for applying this technique in backend Java projects.
Introduced in PHP 7.3, the array_key_first() function returns the first key of an array, with examples showing its usage, handling of empty arrays, and an alternative approach using array_keys() for older PHP versions.
This article introduces the MyBatis‑SQL‑Viewer plugin, detailing its capabilities such as converting MyBatis XML to real SQL, mock data generation, SQL compliance and index checks, execution, performance testing, and how to install and use it within IntelliJ IDEA for efficient backend development.
This article explains the Chain of Responsibility design pattern, demonstrates its use in multi‑step product validation and expense‑approval workflows with concrete Java examples, shows how to configure and assemble handlers dynamically, and discusses the pattern's advantages and drawbacks.
Composer is a PHP dependency manager that automates library installation, version locking, autoloading, and integrates with tools like PHPUnit; the guide explains its core features, installation steps, use of domestic mirrors, global and project‑specific configuration, package requiring commands, and the importance of the composer.lock file.
This article explains how Java 8 functional interfaces such as Function, Supplier, Consumer, and Runnable can replace repetitive if‑else statements, providing code examples for exception handling, branch processing, and present‑or‑else logic to improve readability and maintainability in backend development.
This guide explains why upgrading from Spring Boot 1.5 to 2.1 is essential for MongoDB transaction management, outlines version requirements, highlights key feature changes, and provides step‑by‑step instructions with code examples to enable reliable transactional operations in a Spring‑based backend.
This article explains PHP’s is_float() function, covering its syntax, return behavior, practical usage, and detailed code examples that demonstrate how to check whether variables are floating‑point numbers and handle related conditional logic.
This article shares a recent graduate's three‑year journey at JD, offering practical advice for newcomers, detailing a large‑scale system redesign for a merchant conference, outlining promotion‑season preparation, and describing the development of an AI assistant while emphasizing continuous learning and professional mindset.
This article explains the core concepts of connection‑pool technology, details the architectural choices behind HikariCP such as dual HikariPool instances, FastList, custom ConcurrentBag, ThreadLocal caching, and byte‑code generation, and walks through the key source code that makes the pool exceptionally fast.
The article traces Go's 15‑year journey from its 2009 debut, highlighting its rapid rise in popularity, strong community, advantages over C/C++ and Java, and its pivotal role in cloud‑native, microservice, and AI/ML applications today.
This article clarifies how Inversion of Control (IoC) serves as a design pattern that hands control to an external container, while Dependency Injection (DI) is a concrete IoC implementation that automatically supplies required objects, detailing their definitions, purposes, implementations, and typical usage scenarios.
Spring Framework versions up to 5.3.38 and certain Spring Boot releases contain two severe DoS vulnerabilities (CVE-2024-38808 and CVE-2024-38809); this guide explains their impact, affected products, and provides detailed mitigation steps, including version upgrades and configuration changes to secure your applications.
This article provides a comprehensive overview of Java's ConcurrentHashMap, explaining its purpose, underlying lock‑segmentation and CAS mechanisms in JDK 7 and JDK 8, demonstrating usage with sample code, and outlining scenarios where it delivers high‑performance thread‑safe map operations.
This article provides comprehensive examples of APScheduler's advanced features including database storage, multi-threading/multi-processing, event listeners, dynamic task management, external event triggers, priority settings, logging, advanced triggers, and timezone support.
This article explains the PHP str_split() function, its syntax, parameters, return value, and provides multiple code examples showing how to split a string into characters or fixed‑length chunks and even generate numeric codes for use cases like verification codes.
Rails 7.2 introduces YJIT as the default JIT compiler, requires Ruby 3.3 for default use, adds automatic devcontainer generation with Redis, database, and headless Chrome support, reduces default Puma threads, and includes Brakeman security analysis, delivering notable performance and developer experience improvements.
A Japanese PHP developer released an open‑source project that simulates an operating system using PHP, currently only outputs "Hello World!" in an emulator, and the article provides step‑by‑step installation instructions for macOS and Composer usage.
This article examines common pitfalls in Spring Boot controller design, showcases messy examples, then demonstrates cleaner implementations using @Valid for parameter validation, streamlined exception handling, and best‑practice refactoring to produce more maintainable backend code.
This article explains how the LiteFlow rule engine enables Java developers to define, configure, and execute complex serial and parallel business workflows using XML/JSON/YAML rule files, various node components, data contexts, and runtime parameters, with hot‑deployment and integration examples for Spring Boot projects.
PHP 8 introduces major enhancements such as a Just‑In‑Time compiler, named parameters, improved anonymous classes, and loose type checking, along with numerous other improvements like new error handling, string and array functions, and enhanced return type declarations, all aimed at boosting development efficiency and code quality.
This article explains PHP's is_dir() function, shows how it determines whether a path is a directory, provides basic and advanced code examples for checking and traversing directories, and highlights important usage considerations for reliable file system operations.
This article demonstrates how to transform overly complex Spring Boot controllers—filled with try‑catch blocks, validation logic, and business code—into elegant, concise implementations by applying @Valid, separating concerns, and using global exception handling, illustrated with side‑by‑side code comparisons and practical tips for cleaner backend development.
This article explains the different effects of placing a try‑catch block inside versus outside a for loop in Java, covering usage scenarios, performance impact, memory consumption, and practical recommendations for choosing the appropriate approach during development.
Learn how to use Go's net package for low‑level socket programming—including TCP, UDP, and ICMP connections with the Dial function—and build HTTP clients with net/http, covering basic requests, POST forms, custom headers, and practical code examples.
This article explores how PostgreSQL’s advanced features—UNLOGGED tables, JSONB, SKIP LOCKED, TimescaleDB, pg_cron, PostGIS, full‑text search, JSON generation, pgaudit, and GraphQL adapters—can replace specialized tools like Kafka, Redis, MongoDB, and others, simplifying the tech stack while boosting performance and maintainability.
Learn how to create a fast, modular HTTP load balancer using Rust’s Pingora framework, covering its core advantages, step‑by‑step project setup, code walkthrough, testing, and advanced features like health checks, service discovery, SSL offloading, and traffic control.
This comprehensive guide to backend development explains essential system and architecture design principles, networking strategies, fault and exception handling, monitoring and alerting, service governance, testing methodologies, and deployment practices, offering best‑practice advice and highlighting common pitfalls for building reliable, scalable internet services.
When updating a SpringBoot application the old process must be stopped because the new one cannot bind to the same port, but by leveraging Tomcat's embedded container, ServletWebServerFactory, and dynamic port handling you can keep both processes alive and achieve zero‑downtime deployments.
This article explains how BPC, a PHP native compiler, can translate ThinkPHP8 code into C, outlines the required dependencies, details the migration of the OurBlog sample project, describes necessary code adjustments, and provides step‑by‑step instructions to compile and run the resulting binary.
The article explains that Spring no longer recommends @Autowired field injection, describes constructor‑based, setter‑based, and field‑based dependency injection types, illustrates each with code examples, and outlines the drawbacks of field injection such as immutability issues, SRP violations, and tight coupling to the container.
This article documents a production incident where multiple Spring Boot services each consumed around 12 GB of memory, explains how to diagnose the issue using jps and jmap, details default JVM heap size calculations, and provides recommendations for configuring JVM parameters to prevent excessive memory usage.
The mica‑mqtt component is a simple, low‑latency, high‑performance open‑source MQTT library built on Java AIO that integrates easily into existing services, supports multiple protocols and frameworks, and provides comprehensive documentation, examples, and deployment options for IoT and messaging applications.
This article explains the importance of caching, compares common replacement policies, and walks through a complete Go implementation of a thread‑safe local LRU cache, including interface design, data structures, linked‑list management, and concurrency handling.
This article shares the author's experience of redesigning a microservice using Domain‑Driven Design, detailing a standardized layered architecture, directory structure, model conversions, common pitfalls, and practical recommendations to improve code clarity and testing efficiency.
This tutorial shows how to instrument Spring Boot APIs using Actuator, a custom @Monitor annotation with AOP, and Prometheus to collect and visualize method execution times, providing a complete end‑to‑end monitoring solution.
The article presents a lightweight gray‑release platform for e‑commerce, detailing its four‑module architecture, unified data‑type and predicate rule model, matcher implementations, stable bucket‑based traffic allocation, developer SDK and configuration APIs, as well as whitelist handling and non‑functional considerations for rapid, fine‑grained deployments.
After a year of business coding, the author details the design, implementation, and migration strategy for splitting loan and repayment tables into 50 sharded tables using ShardingSphere with Spring Boot, covering schema design, data synchronization, dynamic switches, and practical pitfalls.
This article introduces the Mall‑Swarm open‑source microservice e‑commerce system, outlines its 2024 video tutorial covering Spring Cloud, Kubernetes deployment, and the full tech stack, and explains how learners can access demos, study materials, and join the learning community.
This guide walks you through installing Nginx, configuring the server, creating a simple HTML page, launching the service, and using a free intranet tunneling tool to make your site accessible from the public internet, all without spending any money on hosting or domain names.
This tutorial walks you through installing Node.js and npm, initializing a project, adding Express, creating routes, handling static files, processing POST requests with body‑parser, implementing simple in‑memory storage, adding error handling, and rendering HTML with EJS, all illustrated with complete code examples.
Learn how to protect PHP source code by creating a custom Zephir‑based encryption extension, covering repository setup, directory structure, licensing logic, abstract and live modules, compilation steps, php.ini configuration, and testing with example authorization codes.
