This article introduces JustAuth, a lightweight open‑source Java library that streamlines third‑party social logins by supporting dozens of platforms, explains its benefits for users and developers, and provides step‑by‑step Maven setup, HTTP client selection, and code examples for basic, builder‑pattern, and custom authentication flows.
Java 17, the newest LTS release, brings a free Oracle JDK under a permissive license and upcoming Spring Framework 6 and Spring Boot 3 support, prompting developers to consider a rapid migration to the modern Java ecosystem.
This guide demonstrates how to set up Spring Boot 2.3.12 with Elasticsearch 7.8, configure separate JPA and Elasticsearch repositories, and implement two batch insertion methods—using ElasticsearchRestTemplate and repository saveAll—while measuring performance, showing comparable execution times for inserting 10,000 records.
This article introduces a collection of essential Java utility libraries—including core Java methods, Apache Commons, Commons BeanUtils, Commons IO, and Google Guava—explaining their key features, Maven dependencies, and practical code snippets for tasks such as string handling, collection operations, object mapping, file I/O, and advanced data structures.
This article traces the historical development from early wired telephones to modern mobile and internet voice services, then details the architecture, features, SIP protocol handling, and Java‑FreeSWITCH integration of the YTalk call platform used for outbound and inbound communications.
This article shares practical experiences and advice on learning software development by copying code, covering where to find source code, official documentation, exemplary implementations, and search engines, and illustrates the approach with real‑world examples from the FunTester testing framework.
This article provides a comprehensive guide to using Spring Boot Actuator for microservice monitoring, covering its purpose, quick setup with Maven/Gradle, detailed explanations of key endpoints such as /health, /metrics, /loggers, and integration with Spring Security for secure access.
This article explains the concept of delayed tasks, compares them with scheduled tasks, and presents five practical implementation strategies—including database polling with Quartz, JDK DelayQueue, Netty's time‑wheel algorithm, Redis sorted‑set and keyspace notifications, and RabbitMQ delayed queues—complete with code samples, advantages, and drawbacks.
The article explains how to protect a flash‑sale inventory using Redis locks in a Spring Boot service, starting with a simple synchronized lock, moving to distributed locks with setIfAbsent, handling lock expiration issues, extending TTL, and finally simplifying the implementation with Redisson.
The SpringOne conference highlighted the upcoming Spring Framework 6.0, detailing its Java 17 and Jakarta EE 9 foundation, roadmap milestones, key migration points, Spring Boot 3 integration, and the imminent Java 17 release, offering developers a clear view of the next decade of Spring development.
The article explains Spring's warning against field injection, compares constructor, setter, and field injection methods with code examples, discusses the drawbacks of field injection such as final‑field incompatibility and hidden dependencies, and recommends using constructor or setter injection for safer, more maintainable code.
This guide explains how to implement periodic tasks in Spring Boot 2.2.11 using the built‑in @EnableScheduling/@Scheduled approach and the Quartz library, covering configuration, cron expressions, core Quartz concepts, and complete code examples for both methods.
This article demonstrates how to construct a full‑text site search solution by selecting Elasticsearch as the search engine, Spring Boot for the backend service, and the IK analyzer for Chinese tokenization, covering environment setup, project architecture, key code implementations, UI pages, and a concise conclusion on the effectiveness of the approach.
This guide explains how to use Maven's archetype plugin to create, customize, install, and share project templates, enabling rapid initialization of new Java projects while excluding unwanted files, and shows both command‑line and IntelliJ IDEA integration for consistent backend development.
This article explains how to use IntelliJ IDEA's Live Template feature to create shortcuts for common Java Stream collector operations such as toList, toSet, joining, and groupingBy, improving code readability and productivity when migrating large codebases to the Stream API.
This article explains the importance of logging in Java web applications, compares popular logging frameworks, introduces the concept of a logging facade, and shows why using SLF4J as a facade provides better decoupling, flexibility, and performance for backend developers.
This article explains how SpringBoot injects HttpServletRequest into controllers using a JDK dynamic proxy and ThreadLocal storage, tracing the request object from the ObjectFactoryDelegatingInvocationHandler through RequestObjectFactory, RequestContextHolder, and the FrameworkServlet's processRequest lifecycle.
This article lists the most popular Java utility classes and their frequently used methods, derived from analysis of 50,000 GitHub projects, helping developers quickly find ready‑made functionality and understand common usage patterns.
The article explains the concept of software scaffolding, why it is needed for microservice development, outlines key design principles, shares a real‑world case of replacing a custom persistence layer with Spring Data, and reviews popular scaffolding tools such as Vue CLI, Maven, Netty, Java EE, Dropwizard and Spring Boot.
This article provides a comprehensive overview of Spring IoC circular dependency problems, explains the three types of circular dependencies, demonstrates them with Java and XML code, and details how Spring resolves singleton setter‑based cycles using its three‑level cache mechanism.
This article provides a comprehensive guide to Java naming conventions, covering package naming, class and interface naming, abstract and exception classes, method and variable naming, constant and enum standards, as well as best‑practice examples and code snippets for each rule.
This roundup covers the Electron 14.0.0 release with new eight‑week cadence and expanded support, StackBlitz's quick Nuxt.js creation, notable open‑source libraries like react‑native‑elements and 7guis‑React‑TypeScript‑MobX, plus deep dives into NestJS practices, React Native's new architecture, Recoil state management, and a comparison of Object versus Map in JavaScript.
JDK 17, the next long‑term support release of Java, entered its final release‑candidate phase with build 35 and brings a host of enhancements—including stricter floating‑point semantics, sealed classes, pattern‑matching for switch, a new RandomGenerator API, and a modern Metal‑based rendering pipeline—while deprecating legacy APIs such as the Security Manager and Applet.
This tutorial explains how to crawl thousands of images from Sogou using Java, detailing the request URL analysis, parameter extraction, multithreaded downloading logic, and providing complete source code for the image processor, pipeline, and HTTP utility classes.
This article compares delayed and scheduled tasks, explains their differences, and presents five practical Java implementations—including database polling with Quartz, JDK DelayQueue, Netty's HashedWheelTimer, Redis sorted sets, and RabbitMQ—highlighting each method's advantages and drawbacks.
This article explains Spring Boot's default logging setup using SLF4J and Logback, demonstrates how to view log levels in a test class, shows how to modify log levels via application properties, and details the underlying XML configuration files and how to customize them for different environments.
The SpringOne conference went online and revealed the upcoming Spring Framework 6.0 built on Java 17 and Jakarta EE 9, outlining its development milestones, key changes from 5.3, cloud‑native enhancements, Spring Boot 3 integration, and the imminent release of Java 17 that will usher in a new era for Java developers.
This article explains how Domain‑Driven Design (DDD) gained popularity alongside microservices, outlines the evolution of software architectures, highlights the boundary‑defining problems of microservices, and shows how DDD’s strategic and tactical design methods help create clear, high‑cohesion, low‑coupling systems.
This article introduces six popular open‑source Spring Cloud microservice projects, detailing their core features, technology stacks, and providing repository links and screenshots to help developers quickly study and adopt enterprise‑grade microservice architectures.
This article explains the role of Spring's MergedBeanDefinitionPostProcessor, showing how it merges bean definitions, invokes post‑processors during bean creation, and enables @Autowired‑related dependency injection with code examples and detailed workflow steps.
This article walks through creating a reusable Redis connection‑pool manager and a functional wrapper class in Java, explaining pooling concepts, resource recycling, and providing ready‑to‑use methods for common Redis commands to support efficient performance testing with the FunTester framework.
This article explains how Spring implements nine classic design patterns—including Simple Factory, Factory Method, Singleton, Adapter, Decorator, Proxy, Observer, Strategy, and Template Method—detailing their implementation mechanisms, core principles, key Spring interfaces, and code examples for each pattern.
This article explains how to avoid out‑of‑memory errors during massive data migrations by choosing appropriate Spring Batch readers, comparing JdbcCursorItemReader and JdbcPagingItemReader, and showing code examples and memory‑usage diagrams.
Linux kernel 5.14 has been promoted to stable, bringing extensive hardware support, core scheduler enhancements, new graphics drivers, expanded ARM and RISC‑V capabilities, and numerous updates for laptops, servers and peripherals, offering developers a richer, more secure platform for modern workloads.
This guide explains the purpose of Spring Boot's @Enable* annotations, how they rely on @Import, and walks through creating a custom @EnablePack annotation with accompanying configuration and usage in a Spring Boot application.
This guide demonstrates how to integrate RocketMQ 4.8.0 into a Spring Boot 2.3.9 application, covering dependency setup, configuration, sending and receiving plain, ordered, clustered, broadcast, and transactional messages, with complete code examples and execution results.
This article explains the history, recent updates, and step‑by‑step usage of the Spring Boot Swagger starter, including dependency setup, detailed configuration options, grouping, JSR‑303 validation support, custom response messages, UI tweaks, ignored parameter types, and authorization settings.
This article explains how to configure and inject List, Map, Set, and array values in Spring applications using @Value annotations, EL expression split functions, default values, and custom parsing methods, providing practical code examples and discussing the advantages and limitations of each approach.
This article explains how to implement efficient real-time WebSocket message pushing in a distributed system by using Redis as a coordination layer, defining Go-based Client and ClientManager components, and detailing the end‑to‑end flow from message production to client delivery.
This guide explains how WebSockets enable full‑duplex communication over a single TCP connection, compares popular Go WebSocket libraries, and provides complete client‑server code examples for TCP, UDP, and HTTP‑based WebSocket implementations, helping developers build real‑time applications such as chat, games, and monitoring tools.
This article explains how to build a simple PHP IoC container with reflection to automatically resolve constructor and method dependencies, demonstrates its use with example classes A, B, and C, and shows how to invoke methods with injected parameters.
The article presents a case study of Xianyu’s extensible user identity and benefits system, explaining how tiered identities grant differentiated product permissions and signal user influence, while detailing an authentication service with three extension points for condition judgment, validation, and audit handling, enabling flexible integration and unified state management.
This article examines the advantages and hidden risks of using Lombok in Java projects, illustrating how its annotations can dramatically reduce boilerplate code while also introducing version compatibility issues, forced dependencies, reduced readability, increased coupling, and technical debt, and suggests alternative approaches for cleaner code.
This article provides an in-depth overview of Java's Collections Framework, detailing the structure, usage, and source code of core interfaces like List, Set, Queue, and Map, and their key implementations such as ArrayList, LinkedList, HashSet, TreeSet, PriorityQueue, ArrayDeque, HashMap, and Hashtable, while highlighting performance characteristics and thread-safety considerations.
This article compares RabbitMQ and Kafka by explaining their architectures, queue consumption and production mechanisms, highlighting RabbitMQ's single‑master limitation and Kafka's partition‑based design for higher throughput, and provides guidance on selecting the appropriate middleware based on performance needs.
This guide explains how to lower the high memory usage of Spring Cloud applications on low‑end machines by adjusting per‑project JVM options in IntelliJ IDEA, detailing the necessary -Xmx, -Xms, -Xmn and -Xss parameters and showing the resulting performance improvement.
The article details the design and implementation of a dedicated pricing calculation engine that decouples complex e‑commerce promotion logic from transaction services, using componentized rules, configurable pipelines, multi‑level caching, and lane‑based simulations to achieve high extensibility, low latency, and accurate pricing across browsing and checkout scenarios.
This step‑by‑step tutorial explains how to create Restful file upload and download APIs using Spring Boot 2.2.6, covering environment setup, project structure, interface and implementation details, size‑limit configuration, global exception handling, and testing the endpoints with Postman.
This article explains the principles behind Linux's epoll mechanism, how IO multiplexing enables a single thread to manage many file descriptors efficiently, the role of non‑blocking sockets, and why epoll outperforms select and poll for high‑concurrency network services.
This article explains how Spring Boot's auto‑configuration works by loading configuration classes from spring.factories, using @EnableAutoConfiguration and conditional annotations to bind properties from application.properties or application.yml to beans such as ServerProperties, enabling rapid backend development without extensive manual setup.
Learn how to configure a Spring Boot 2.3.11 project with MyBatis 3.5.6, set up dependencies, pagination, mapper scanning, define mapper interfaces with annotations, implement dynamic SQL providers, and write comprehensive unit tests to verify CRUD operations.
The article details Vivo Mall’s new promotion pricing engine, which replaces duplicated site‑level logic with a layered model (product, shop, platform) that supports configurable stacking, processes discounts through three calculation stages, and uses a meta‑driven rule engine to flexibly interpret JSON promotion templates, ensuring extensible, stable pricing functionality.
This article walks through converting a Go‑based TCP private‑protocol server to support WebSocket on the same port, covering library selection, client and server implementation, request upgrading, and a complete usage example with code snippets.
The article presents a domain‑specific language that mimics Excel formulas, a stack‑based parser and recursive engine for evaluating calculations, and a multi‑layer architecture—including a dynamic priority scheduler—to efficiently resolve field dependencies, improve maintainability, and enable monitoring across large data systems.
This article explains the fundamentals of message queues, compares point-to-point and publish‑subscribe models, introduces Java Message Service (JMS) and its programming model, and provides an overview of popular MQ implementations such as RabbitMQ, ActiveMQ, RocketMQ, and Kafka, highlighting their architectures and use cases.
This article explains how Spring's @Autowired annotation works across constructors, methods, fields, arrays, collections, maps, optional dependencies, and special beans, providing practical code examples and important notes on required flags, ordering, and usage restrictions.
This article explains Spring's pointcut implementations, covering static and dynamic pointcuts, regular‑expression based pointcuts, the RegexpMethodPointcutAdvisor, control‑flow pointcuts, and how to create custom pointcuts by subclassing Spring’s abstract pointcut classes, with full XML and Java code examples.
This article examines the consistency challenges of using Redis as a cache, compares three update strategies—updating the database before the cache, deleting the cache before updating the database, and updating the database then deleting the cache—analyzes their pitfalls, and presents practical solutions such as delayed double‑delete, asynchronous retries, and binlog‑driven cache invalidation.
This article reviews various cache system types, compares popular distributed caches such as Memcache, Tair, and Redis, explains Redis cluster high‑availability mechanisms, discusses sharding strategies, and outlines common cache problems and solutions, providing practical configuration examples for Java backend developers.
This article explains cache consistency problems and solutions such as double‑delete and retry mechanisms, dives into Java fundamentals like HashMap internals and thread pools, and presents several backend interview coding questions with examples and code snippets.
After encountering duplicate order IDs during a system upgrade, the author analyzes the shortcomings of the original timestamp-and-random-based generator, demonstrates concurrency tests revealing collisions, and presents a revised Java implementation using atomic counters, shortened timestamps, and IP suffixes to reliably produce unique order numbers even under high load.
Spring MVC lets developers retrieve request data using the raw HttpServletRequest, or more conveniently with annotations such as @RequestParam, @RequestHeader, @RequestBody, and @CookieValue, supports automatic binding to POJOs including nested objects, injects native Servlet objects like HttpSession, and handles character encoding via CharacterEncodingFilter.
This article demonstrates how to use Fluent MyBatis, native MyBatis, and MyBatis‑Plus to query a student_score table for term‑wise statistics of English, Math, and Chinese scores, providing complete code examples, SQL statements, mapper definitions, and code‑generation configurations for each approach.
This article explains the avalanche effect caused by synchronous service calls, lists common scenarios, and demonstrates how to use Netflix Hystrix—through thread isolation, circuit breakers, and fallback methods—to protect backend services from cascading failures, complete with practical Java examples.
Midway 2.0 introduces a runtime‑based Hook system, removes compiler constraints, enables faster startup under 2 seconds, supports code reuse, new middleware models, flexible configuration via midway.config.ts, enhanced testing utilities, and broader deployment scenarios including web servers, all backed by open‑source Vite and Prisma integrations.
This article explains the three RabbitMQ exchange patterns—Direct, Fanout, and Topic—detailing how each routes messages, when to use them, and providing visual flowcharts to illustrate their operation in distributed backend systems applications.
This article explains how to use OpenResty with Lua to build a high‑performance caching layer that directly accesses Redis, compresses large responses, schedules periodic updates, forwards requests intelligently, and provides configurable URL caching, thereby improving concurrency, reducing latency, and optimizing bandwidth usage.
This interview explores the six‑year evolution of the dubbogo project, the motivations, challenges, and biggest contributions of PMC member Wongoo, and his vision for the future of this high‑quality Go implementation of the Dubbo RPC framework.
This article explains the inner workings of Spring Cloud's RefreshScope, covering its annotation definition, registration in the auto‑configuration, the refresh endpoint workflow, event handling, and how beans annotated with @ConfigurationProperties or @RefreshScope are dynamically refreshed at runtime.
This article explains the fundamentals of Domain‑Driven Design (DDD), outlines its strategic and tactical design processes, and demonstrates how Haro’s transaction platform applies DDD across taxi, e‑commerce, and core trading scenarios, highlighting benefits, challenges, and practical recommendations.
This guide demonstrates how to create a custom request‑handling method, register it programmatically with Spring MVC's RequestMappingHandlerMapping, and explains the underlying handler detection and mapping process in Spring Boot 2.2.
This article recounts the author’s experience building a simple Java web application for a university anniversary, covering planning, environment setup, documentation, database design, coding challenges with Spring Boot, Redis, and session handling, deployment on Alibaba Cloud, and the lessons learned about architecture, logging, and monitoring.
This comprehensive guide dives deep into Spring Validation, covering basic usage, dependency setup, requestBody and requestParam validation, group and nested validation, custom constraints, fail‑fast mode, and the underlying implementation in Spring MVC and AOP, all with practical code examples.
The article explains why multithreading is essential for modern CPUs, introduces thread pools to reduce overhead, and details Java's ThreadPoolExecutor creation parameters, execution process, and core methods such as addWorker, runWorker, and getTask, using JDK 1.8 source code examples.
This article presents a comprehensive guide to using Redis for various backend scenarios, including caching hot data, sharing sessions, implementing distributed locks, generating global IDs, counting, rate limiting, bitmap statistics, shopping carts, timelines, message queues, lotteries, likes, tags, product filtering, follow relationships, and ranking, all illustrated with concrete code examples.
This article explains how to fix KindEditor image upload errors caused by PHP's upload size restrictions by modifying the php.ini upload_max_filesize setting and increasing the $max_size value in KindEditor's upload_json.php file.
This article walks through the Spring Security authentication flow in a Spring Boot 2.2.11 application, detailing filter execution, token creation, provider selection, custom DaoAuthenticationProvider configuration, and session management, complemented by code snippets and diagrams for each step.
This article examines four major API architectural styles—RPC, SOAP, REST, and GraphQL—explaining how each works, outlining their advantages and disadvantages, and providing guidance on selecting the most suitable style for different project requirements.
This article outlines the ten most frequent errors developers make when using the Spring framework—ranging from over‑focusing on low‑level details to neglecting proper testing—and provides concrete best‑practice solutions with code examples to improve code quality, maintainability, and reliability.
This article explains how to use Spring Boot's @ControllerAdvice and @ExceptionHandler annotations to implement clean, global exception handling, covering basic usage, controller‑specific handlers, and ordered advice for multiple handlers, with practical code examples and diagrams.
This article introduces essential Java utility libraries—including built‑in methods, Apache Commons, and Google Guava—showing practical code snippets and Maven dependencies that help developers reduce boilerplate, improve readability, and boost productivity across backend projects.
The article explains Java’s automatic memory management, detailing JVM memory regions, object liveness via reachability analysis, allocation strategies, and the main garbage‑collection algorithms—Mark‑Sweep, Mark‑Copy, Mark‑Compact—and compares HotSpot collectors such as Serial, Parallel, CMS and G1, guiding developers to choose the best fit for their workloads.
This article outlines the objectives, detailed call flow, architectural design, and potential challenges of a unified payment center that consolidates order, payment, and financial services across multiple business lines, providing a secure, extensible, and data‑driven backend solution.
This article explains the design and architecture of a cloud-based shopping cart system, covering its functional modules, layered and cluster designs, distributed goals such as stability and elasticity, three-level caching, asynchronous checks, heterogeneous storage, payment solutions, and anti‑scalping measures.
This article outlines the career path toward software architecture, detailing the market expectations, essential competencies such as project management, technical depth, business insight, communication, decision‑making, and optimization techniques for systems, backend services, and databases, while emphasizing continuous learning and community involvement.
This article details the design and architecture of a cloud‑based shopping cart system, covering its functional modules, layered and cluster designs, technical goals such as stability and elasticity, three‑level caching, asynchronous checks, storage heterogeneity, and payment‑processing solutions.
This guide explains how to replace the old Alipay transfer interface with the new certificate‑based alipay.fund.trans.uni.transfer API, upgrade the SDK, configure certificates, add Maven dependencies, and implement Spring‑Boot beans and utility classes for secure payment and transfer operations.
HTTP/2, now widely supported by browsers and major sites, replaces HTTP/1.1 by introducing a binary framing layer, header compression, stream prioritization, server push, and flow control, addressing head-of-line blocking and inefficiencies while maintaining HTTP semantics, with detailed discussion of its evolution, structure, and deployment considerations.
Designing a flash‑sale (秒杀) system for massive concurrent users requires careful handling of instant traffic spikes, page staticization, CDN acceleration, caching strategies, distributed locks, rate limiting, asynchronous processing, and reliable stock management, with nine detailed techniques to ensure stability and prevent overselling.
This article explains four Spring‑Boot techniques—traditional AOP, HandlerInterceptor, HandlerMethodArgumentResolver, and Servlet Filter—to implement a reusable appkey whitelist validation, provides complete code examples for each, and clarifies their execution order within the request processing pipeline.
This article provides a comprehensive overview of Spring Batch, covering its purpose, architecture, core components such as Job, Step, ItemReader/Writer/Processor, execution contexts, chunk processing, skip strategies, and practical tips for configuration and memory management.
This article explains the AKF scalability cube for microservice architecture, detailing the Y‑axis functional decomposition, X‑axis horizontal scaling, Z‑axis data partitioning, as well as front‑end/back‑end separation, stateless services, and RESTful communication, providing practical diagrams and guidance for building robust, scalable systems.
This article explains the proxy design pattern, demonstrates its static implementation with Java code, and shows how Nacos Client leverages a custom proxy delegate to switch between HTTP and gRPC protocols, highlighting structural roles, practical usage, and differences from the decorator pattern.
This guide demonstrates how to configure and test various Spring Cloud Gateway filter factories—including AddRequestHeader, AddRequestParameter, AddResponseHeader, PrefixPath, StripPrefix, Retry, RedirectTo, and default filters—using Spring Boot 2.3.7 with Hoxton.SR9, complete with YAML snippets and code examples.
This article examines Lombok’s ability to shrink Java boilerplate, walks through code transformations from verbose getters and setters to concise annotations, and critically evaluates five major drawbacks—including JDK compatibility, forced adoption, readability loss, tighter coupling, and technical debt—offering guidance on when to avoid it.
This article explains the common points where messages can be lost in RabbitMQ and Kafka, compares transaction and confirm mechanisms, describes how to enable persistence and proper acknowledgments, and provides concrete configuration recommendations for producers and consumers to ensure reliable message delivery.
imageaffine is a PHP function that applies an affine transformation to a given image resource, optionally using a clipping rectangle, returning the transformed image on success or FALSE on failure, with detailed parameter specifications for the image, affine matrix, and clipping area.
This article explains the motivation, design principles, model architecture, and implementation challenges of rebuilding ByteDance's Node.js RPC system, covering DDD‑based decomposition, protocol and connection abstractions, multi‑protocol nesting, client/server creation APIs, and performance‑optimized context extensions.
This article presents a comprehensive collection of Baidu C++ engineers' performance‑optimization practices, covering memory‑access patterns, string handling, protobuf manipulation, allocator choices, job‑level memory arenas, cache‑line considerations, and memory‑order semantics to achieve substantial latency and cost reductions in large‑scale backend services.
This article walks through the evolution of an online supermarket from a simple monolithic website to a fully split micro‑service system, highlighting the motivations, architectural changes, operational challenges, and the tooling needed for monitoring, tracing, logging, and resilient deployment.
