This guide explains common business scenarios that require custom SQL parsing, walks through setting up Antlr4 in IntelliJ IDEA, configuring Maven dependencies, generating parser code, and provides Java examples for extracting table names from Spark SQL statements, including handling of prediction modes and execution results.
This article explores common misconceptions and practical strategies—including write ordering, delayed double‑delete, retry mechanisms, and scheduled cleanup jobs—to ensure reliable dual‑write consistency between MongoDB and traditional relational databases.
This guide explains how to implement declarative retry mechanisms in Java using Spring‑Retry and Guava‑Retry, covering dependency setup, template and annotation usage, various retry and back‑off policies, test examples, and a comparative analysis of their flexibility and configuration options.
This article explains how front‑end engineers can transition from traditional static‑site deployment to fully cloud‑native web applications by leveraging Alibaba Cloud’s Serverless services—OSS, CDN, and Function Compute—to achieve automatic scaling, zero‑ops maintenance, cost efficiency, and enhanced security for dynamic APIs, tasks, and media processing.
This article explains why using Go's init() function is discouraged due to readability, testing complications, and error‑handling limitations, and it offers practical alternatives such as direct variable initialization, custom init functions with sync.Once, and controlled error‑aware initialization patterns.
This article explains the fundamentals of caching, why caches like Redis are essential for high‑performance and high‑concurrency backend systems, and compares local, distributed, and multi‑level cache architectures, including their advantages, drawbacks, and typical implementation approaches.
This article explains how to use PHP's mysqli extension to establish and close MySQL connections, handle connection errors, perform CRUD operations, process query results, execute multiple statements, and manage transactions, providing code examples for each step.
This article explains why distributed ID generation is needed, outlines business requirements such as global uniqueness and monotonicity, and compares eight practical schemes—including UUID, database auto‑increment, segment mode, Redis, Snowflake, Baidu UidGenerator, Meituan Leaf, and Didi TinyID—detailing their advantages, disadvantages, and implementation examples.
This article introduces microservice architecture, explains its key characteristics, ecosystem components such as load balancers, service discovery, API gateways, monitoring, containerization, and circuit breakers, compares it with monolithic architecture, outlines common challenges, and outlines scenarios where adopting microservices is advantageous.
This article explains the concepts, design principles, and practical implementation steps of an open‑source decision engine—covering rule vs. decision flow, DSL creation with YAML, operator handling, workflow orchestration, and deployment considerations for production environments.
This article examines layered monolithic architecture styles, comparing classic four‑layer designs with five‑layer variants, discussing their benefits, trade‑offs, impact on complexity, change isolation, and how modular thinking can bridge the gap between technical layers and business domains.
JDEasyFlow is an open‑source Java workflow orchestration component from JD's enterprise finance R&D team that supports JSON and BPMN specifications, offers flexible node types, modular architecture, and provides detailed usage examples and implementation principles for building scalable process‑driven applications.
The article details how a Java team diagnosed frequent Full GC pauses caused by CMS, migrated to G1GC, adjusted JVM flags, scaled container specs, and achieved dramatically lower pause times, reduced instance counts, and significant cost savings while improving overall service stability.
This article explains why distributed ID generation is essential for modern micro‑service architectures, outlines the key requirements such as global uniqueness and monotonicity, and compares popular solutions like UUID, database auto‑increment, segment mode, Redis, Snowflake, Baidu UidGenerator, Meituan Leaf, and Didi TinyID with practical code examples.
This article shares eighteen practical techniques—including batch database operations, asynchronous processing, caching, prefetching, pooling, event callbacks, parallel remote calls, lock granularity, file‑based staging, indexing, SQL tuning, transaction management, deep pagination fixes, code restructuring, payload compression, NoSQL adoption, thread‑pool tuning, and JVM/IO optimizations—to dramatically reduce backend interface latency and improve overall system performance.
The article explains the business scenarios that require timed tasks, compares single‑machine and distributed scheduling frameworks such as Quartz, TBSchedule, elastic‑job, Saturn and xxl‑job, and provides a detailed evaluation of their features, deployment models, sharding strategies, high‑availability and monitoring capabilities to guide developers in choosing the right solution.
This article revisits Adam Wiggins' 12‑Factor App methodology, explaining how each factor—from codebase and dependencies to logging and admin processes—has evolved and why these principles remain crucial for building reliable, scalable micro‑service‑based backend systems today.
This article provides a comprehensive step‑by‑step migration guide for upgrading Spring Boot applications to version 3.0, covering JDK updates, dependency assessment, configuration changes, Jakarta EE package renaming, key feature alterations, and practical code snippets.
This article presents a comprehensive overview of payment system architecture, detailing the core transaction and payment modules, system interactions, service governance, data consistency strategies, asynchronous processing, and practical production practices such as performance testing, stability management, and service isolation.
The article explains how to protect a suddenly hot product API in an e‑commerce system by applying caching, various rate‑limiting algorithms, service degradation techniques, and distributed caching patterns, providing concrete Java code and architectural recommendations for backend developers.
This article provides a comprehensive visual tutorial on Git’s core commands—including add, commit, reset, checkout, diff, merge, rebase, and cherry‑pick—explaining their effects on the working directory, staging area, and repository while illustrating concepts such as HEAD, branches, and detached states.
This article reviews several Java backend technologies—JSP, Struts, Hibernate, Servlet, Applet, Swing, JDBC, and XML—explaining why they are becoming obsolete or less essential and offering guidance on which ones learners can safely skip or deprioritize.
The article explains Taobao’s Atmosphere visual marketing system, detailing the need for an Atmosphere Center, its three‑tier architecture with dual configuration portals, Diamond‑based synchronization, abstract handler classes for CRUD operations, and future plans to consolidate portals and streamline custom logic.
Spring Boot 3.0, the first major release since 2.0, introduces Java 17 baseline, GraalVM native image support, enhanced observability with Micrometer, and Jakarta EE 10 compatibility, while providing a detailed migration guide for upgrading from earlier Spring Boot versions.
This article explains NGINX’s hot‑reload mechanism, its limitations in high‑frequency cloud‑native environments, and how Apache APISIX provides an in‑memory, zero‑downtime solution for dynamic configuration updates.
This article examines traditional RBAC, ABAC, and PBAC access‑control models, evaluates their strengths and weaknesses, and presents a hybrid permission architecture tailored for 微盟's WOS system that combines role‑based and attribute‑based rules to achieve high flexibility and fine‑grained authorization.
This article explains how Domain‑Driven Design (DDD) guides the strategic and tactical decomposition of monolithic applications into well‑bounded microservices, outlines its benefits such as a unified language and clearer domain boundaries, and provides concrete code examples from a membership‑center service.
This article explains how to use Spring Validation for automatic request parameter checks in Java web applications, covering basic setup, DTO annotations, requestBody and requestParam validation, unified exception handling, and advanced features like group, nested, collection, custom, and fail‑fast validation.
The article explains various techniques for ensuring data consistency in distributed microservice architectures, including blocking retries, asynchronous queues, TCC compensation transactions, local message tables, and MQ transactions, while discussing their advantages, drawbacks, and practical implementation details.
The article presents comprehensive best‑practice guidelines for building a clean, maintainable Controller layer in Spring MVC, covering its essential responsibilities, common pitfalls, unified response structures, parameter validation with JSR‑303, custom validators, and centralized exception handling to improve code simplicity and robustness.
This guide presents a concise set of best‑practice rules for designing consistent, resource‑oriented RESTful APIs, covering naming conventions, URL structures, HTTP methods, versioning, pagination, security, monitoring, and documentation to improve developer experience and system reliability.
This tutorial provides a complete, step‑by‑step guide to automatically deploy a Spring Boot project on CentOS 7 by installing Docker and Jenkins, configuring Maven and required plugins, creating a Jenkins pipeline, building the Docker image, and running the container, while avoiding common pitfalls.
The article explains how to design a payment account system for e‑commerce, distinguishing payment accounts from login credentials, outlining key requirements such as transaction, accounting, reconciliation, risk control and credit, and detailing entity, account, and transaction models with attributes and control rules.
This article explains how to design and implement instant (秒传), chunked (分片上传), and resumable (断点续传) file upload mechanisms in Java, covering the underlying MD5 deduplication logic, Redis state tracking, server‑side file handling with RandomAccessFile and MappedByteBuffer, and practical deployment considerations.
This article explains the fundamental differences between HTTP and RPC, covering protocol layers, communication formats, performance considerations, RPC architecture, synchronous vs asynchronous calls, popular RPC frameworks, and when to choose RPC over HTTP for backend services.
This article examines Elasticsearch's three pagination strategies—basic from/size, scroll-based deep paging, and the newer search after method—detailing their execution phases, performance implications, code examples, and practical recommendations for choosing the appropriate approach based on data volume and real‑time requirements.
This article explains what API idempotency is, why it is needed, which interfaces should be idempotent, and presents various implementation methods such as frontend interception, database unique indexes, optimistic and pessimistic locks, JVM locks, distributed locks, and token‑based approaches.
This article explains why browsers enforce same‑origin policies, presents common CORS solutions such as the @CrossOrigin annotation, gateway integration with Spring Cloud Gateway, and using HttpClient, and provides detailed configuration and code examples for implementing these approaches in a Java backend project.
DTLE 4.22.11.0 introduces major job configuration changes, new log settings, a TwoWaySync parameter for bidirectional replication, beta Kafka credentials, and fixes for Decimal column defaults, while providing updated documentation links and download resources for the open‑source MySQL data transfer component.
This article presents a comprehensive engineering guide for building a high‑performance e‑commerce search engine with Go (Kratos), Elasticsearch/OpenSearch, Redis, MySQL, and Kafka, covering architecture, index construction, query processing, ranking, user‑guidance features, and future extensions such as recommendation and visual search.
The article explains how using a Redis cache can boost read performance but introduces consistency challenges, compares four cache‑aside write strategies, and recommends the reliable “update database then delete cache” approach combined with short expiration times and asynchronous message‑queue invalidation to keep data fresh.
This article explains why specifying an initial capacity for Java's HashMap matters, illustrates common misuse cases, walks through the source code to show how capacity and resizing thresholds are calculated, and provides guidelines for choosing the correct capacity to avoid unnecessary rehashing.
This article examines the challenges of scaling JD's shopping cart, proposes a paginated loading strategy for auxiliary product information to reduce backend load and improve user experience, and details the technical design, pagination options, pre‑loading mechanisms, and measured performance benefits.
An in‑depth case study of a data‑service company's transition to microservices details the initial benefits such as visibility and reduced deployment cost, the subsequent problems of queue head blocking, shared‑library versioning, scaling complexity, and the eventual trade‑offs that led to a partial monolith rollback.
This article explains how to use SLF4J's MDC to attach a request identifier to log entries, demonstrates the limitation of MDC in asynchronous threads, and provides a decorator‑pattern solution (MDCRunnable) that propagates the context, enabling reliable log correlation across threads in Java backend applications.
Node.js v19.1.0 introduces function mocking in the test runner, recursive file‑system watching support, updated ICU, documentation collaborator additions, removal of experimental fetch warnings, MIME utilities, and performance improvements for text decoding, providing a comprehensive set of backend enhancements.
This article explains why short URLs are useful, describes the principle of mapping short codes to original URLs, and provides two complete PHP implementations—one using MySQL for storage and another using an INI file—along with the necessary rewrite rules for Apache and Nginx.
This article walks through turning a basic personal‑blog architecture—single server, MySQL, and Node.js—into a high‑concurrency system by adding Redis caching, Nginx load balancing, horizontal scaling, read‑write splitting, sharding, NewSQL databases, and message‑queue techniques.
The article analyzes the challenges of keeping cache and database consistent after write operations, evaluates four update‑order strategies, discusses their concurrency pitfalls, and presents practical solutions such as CAS, distributed locks, asynchronous updates, and delayed double‑delete techniques.
This article provides a comprehensive overview of payment system architecture, describing the transaction and payment cores, their interactions, service governance, asynchronous processing, data consistency, performance testing, and production practices, while illustrating each component with diagrams and practical insights.
This article explains the need for globally unique identifiers in modern applications, outlines the essential characteristics of a distributed ID generation service, examines common implementation techniques, and discusses concrete business scenarios such as order numbers, coupons, short URLs, and tracing with practical code examples.
This article describes the background, design decisions, architecture, core concepts (Serverless, BFF, FAAS), implementation details, performance results, and future plans of the internally built Seras platform that enables front‑end teams to write cloud functions without managing servers, improving code reuse, traceability, and deployment speed.
This article explains the backend technology choices for a low‑code poster platform, covering Node.js framework selection, database decisions (MySQL, MongoDB, Redis), authentication methods (Session vs JWT), and unit/integration testing tools such as Mocha, SuperTest, and related code examples.
This article explains how to build a modular backend service in Java using domain‑driven design, configurable modules, dynamic proxies, cache adapters, lambda‑based query conditions, and Spring‑based conditional bean loading to enable flexible extensions without altering existing code.
This article explains the concept of idempotent HTTP requests, defines idempotency, lists which HTTP methods are idempotent or not, and clarifies why methods like GET, HEAD, PUT, DELETE are safe to retry while POST, PATCH, and CONNECT are not.
This article explains how to overcome performance bottlenecks of a rapidly growing blog by progressively enhancing the traditional Nginx‑MySQL stack with load‑balanced app servers, Redis caching, read/write splitting, MySQL partitioning, MyRocks, and finally a hybrid NoSQL‑big‑data architecture using Hadoop and HBase.
This article explains why a server must invoke listen() after bind(), detailing the kernel's listen system call, how it creates and initializes the full‑connection and half‑connection queues, and how their lengths are calculated based on backlog, somaxconn, and tcp_max_syn_backlog parameters.
This article provides a thorough overview of backend development, covering system development principles, architectural design patterns, network communication techniques, common faults and exceptions, monitoring and alerting strategies, service governance practices, and deployment workflows, all illustrated with clear explanations and practical examples.
This article explains the behavior of NaN values in Go maps, demonstrates a related IEEE‑754 quiz, and discusses the ongoing proposal to introduce a delete(m) function that can reliably clear maps even when they contain NaN keys.
This article details how JD's retail shopping‑cart team tackled growing business complexity by fully converting the cart service to an asynchronous architecture, addressing challenges such as increasing RPC dependencies, pagination, and resource costs, and achieving a 30% reduction in core interface latency.
The article explains how to select and implement routing keys for database sharding in an order platform, covering time‑based and business‑related keys, user and merchant scenarios, hash‑modulo strategies for single and multi‑database environments, and the overall data flow.
The article explains why calling PHP's session_start() multiple times generates duplicate Set-Cookie headers, provides a code-based fix using session_abort() and header_remove(), and discusses session file locking, cookie lifetime, and garbage collection settings to manage session behavior effectively.
This article details a systematic approach to reducing image sizes for ISV‑generated pages, covering offline compression, WebP conversion, data structure design, batch processing pipelines, monitoring, and fallback strategies, while providing code examples and performance comparisons.
This article provides a comprehensive overview of process engines, explaining their definition, relationship to workflows and BPM, design of process designers, various application scenarios such as workflow and BPM, detailed architectural components, implementation practices, and potential business opportunities, illustrated with diagrams and XML examples.
This article explains common cache update patterns—Cache Aside, Read‑Through, Write‑Through, and Write‑Behind—illustrates their read/write flows, highlights typical pitfalls such as dirty data caused by wrong update order, and offers practical safeguards for maintaining data consistency in large‑scale systems.
This guide walks you through installing the MyBatisCodeHelper‑Pro IntelliJ plugin, configuring it to generate Java entity, DAO, mapper and service code, customizing type mappings, creating SQL scripts, and using shortcuts to produce find, update, delete, and pagination methods efficiently for backend development.
This article provides a detailed tutorial on Spring Security, covering its core concepts, project setup, authentication flow, custom user details service, password encoding, login handling, role-based access control, CSRF protection, and integration with Thymeleaf, complete with code examples.
The article explains why front‑end and back‑end should be separated, outlines the challenges of integration, describes the responsibilities and development process for a clean API contract, and provides detailed request/response specifications with code examples for building a maintainable SPA architecture.
This article explains how to size Redis memory, configure maxmemory and maxmemory‑policy settings, and choose among various eviction strategies—including no‑eviction, allkeys‑lru, allkeys‑lfu, and volatile options—while detailing the underlying LRU and LFU algorithms used by Redis.
The article discusses the importance of clear application layering, outlines Alibaba’s multi‑layer architecture, proposes an optimized layering model, explains domain object types (DO, DTO, BO, AO, VO, Query) and offers practical guidelines to improve code maintainability and reuse in backend development.
This article examines how adopting software frameworks—especially web frameworks—can undermine long‑term maintainability through control inversion, mismatched goals, design trade‑offs, and hidden costs, while also showing how a decoupled approach can retain benefits without the drawbacks.
The article evaluates common approaches for implementing delayed tasks such as order‑closing, critiques unreliable methods like Redis expiration listeners and RabbitMQ dead‑letter queues, and recommends robust solutions like RocketMQ, Pulsar, or Redisson delay queues with proper compensation mechanisms.
This article walks through the complete design and implementation of a high‑performance user login system, covering client‑side verification, server‑side token generation, token expiration strategies, gateway authentication, logout handling, anonymous request allowances, rate‑limited auth tokens, and blacklist management, illustrated with diagrams and Java Spring code examples.
The article examines three approaches to handling inventory deduction in e‑commerce—single‑field MySQL, sharded MySQL rows, and Redis incrby—analyzes their concurrency drawbacks, and presents a robust Redis‑Lua script solution with distributed locking and Java implementation details.
This article explains Netty's high‑performance asynchronous architecture, compares classic multithread, Reactor, select, poll and epoll I/O multiplexing models, describes level‑triggered versus edge‑triggered event handling, and provides a step‑by‑step JNI example and a hand‑written epoll server implementation in C.
This guide walks through setting up a Python 3.8 environment, configuring SQL Server authentication, installing pymssql and ttkbootstrap, and running a Tkinter‑based application via command line or Visual Studio, complete with screenshots and a QR code for additional Python learning resources.
This article explains the differences between short and long connections, why long‑connection services need load balancing, and presents practical strategies for connection‑level balancing, handling server restarts, heterogeneous hardware, and scaling challenges.
This article explains the fundamentals of in‑memory caching, introduces Guava's LoadingCache API, discusses cache sizing, eviction policies, common algorithms like FIFO, LRU, LFU, shows a simple LRU implementation using LinkedHashMap, and provides practical guidance on when and how to apply caching for performance optimization.
This article provides a comprehensive overview of Dubbo, a high‑performance Java RPC framework, detailing its three core capabilities, essential components, layered architecture design, and the step‑by‑step remote invocation workflow for both service providers and consumers.
This article provides an in‑depth overview of microservice architecture, covering its definition, history, differences from monolithic and SOA approaches, core characteristics, design patterns, advantages and drawbacks, practical deployment considerations, and recommended reading resources.
This article explores the fundamentals of data saving for web‑based tools, covering what data is saved, where it is stored (backend vs. frontend), various trigger mechanisms, design principles for reliable saving, and feedback patterns to ensure users never lose their work.
This article explains how Netty implements a powerful asynchronous, event‑driven architecture using the Reactor pattern, compares classic multithread, select, poll and epoll I/O multiplexing models, demonstrates JNI integration with Java, and provides a complete, annotated epoll server example with level‑triggered and edge‑triggered handling for high‑concurrency backend development.
This article examines how the mic‑queue list in a live‑streaming app caused heavy server load due to three‑second polling, and details a systematic performance‑optimization process—including analysis, reducing I/O, employing Go’s singleflight caching, and switching JSON libraries—to cut resource usage by up to 60% while preserving user experience.
This article examines common misconceptions about application layering, outlines Alibaba's multi‑layer architecture—including Open Interface, Terminal Display, Web, Service, Manager, and DAO layers—offers optimized layering practices, explains domain model transformations, and provides actionable guidelines for building maintainable, reusable backend systems.
Node.js 19, released today, updates the V8 engine to version 10.7, enables experimental node --watch mode, defaults HTTP/1.1 Keep‑Alive, stabilizes the WebCrypto API, removes experimental specifier‑resolution flag, and deprecates DTrace/SystemTap/ETW support while bundling llhttp 8.1.0 and npm 8.19.2.
This article explains how to use Java's java.util.concurrent.Semaphore together with a fixed-size thread pool to enforce a precise QPS limit for asynchronous tasks, providing API details, implementation steps, and a complete test example.
This article explains the browser same‑origin policy, defines cross‑origin requests, outlines the restrictions they impose, and presents five practical ways—global filter, WebMvcConfigurer, @CrossOrigin annotation, manual response headers, and a custom filter—to enable CORS in a Java Spring MVC backend with complete code examples.
This comprehensive guide explains how to configure Nginx as an HTTP server, static file server, reverse proxy, and load balancer, covering directory setup, location matching rules, priority order, upstream strategies, and useful directives such as return, rewrite, error_page, logging and access control.
This article provides a comprehensive overview of various load balancing strategies—including round‑robin, random, weighted, smooth weighted round‑robin, consistent hashing, least‑active, and optimal‑response algorithms—explaining their principles, advantages, disadvantages, use‑cases, and offering complete Java code examples for each.
The author recounts his 2023 autumn recruitment experience, detailing his background, internships, extensive job applications, interview outcomes, study strategies covering fundamentals, design patterns, and distributed systems, and offers practical advice for fellow graduates navigating the competitive tech job market.
The article explains how microservice architectures can achieve high availability by isolating failures, employing graceful degradation, change‑management strategies, health checks, fallback caching, retry logic, rate limiting, circuit breakers, and chaos testing, while acknowledging the added complexity and cost of such reliability engineering.
This article explains what ULID is, why it can be a better alternative to UUID, outlines its key characteristics and specification, and provides practical Python examples for generating and handling ULIDs in distributed backend systems.
The article builds five microservices with Helidon SE, Ktor, Micronaut, Quarkus and Spring Boot, integrates Consul for service discovery, provides full source code and configuration, shows how to start each service, benchmarks size, startup time and memory usage, and finally lists the pros and cons of each framework.
This article walks through the evolution of a simple online supermarket from a monolithic website to a fully split microservice architecture, highlighting the challenges encountered—such as code duplication, database bottlenecks, and operational complexity—and presenting practical solutions like service decomposition, monitoring, tracing, gateway control, service discovery, circuit breaking, rate limiting, testing strategies, and the use of service meshes.
This tutorial walks through multiple Python approaches for downloading files—including simple requests.get calls, the wget module, handling redirects, chunked large‑file downloads, parallel batch downloads, proxy usage with urllib, S3 retrieval via Boto3, and asynchronous fetching with asyncio—providing code examples and best‑practice tips.
This guide explains how to upgrade to Alipay’s new transfer interface, alipay.fund.trans.uni.transfer, by updating the SDK, configuring certificates, adding Maven dependencies, and implementing Java Spring beans and utility classes for secure fund transfers.
Spring 6 introduces major updates such as moving JSR‑330 and JSR‑250 annotations to Jakarta packages, deprecating ListenableFuture, requiring Hibernate 5.6.x with jakarta.persistence, updating servlet containers, altering controller detection, converting HttpMethod to a class, and adjusting Kotlin and RestTemplate APIs.
This article presents thirteen practical guidelines for optimizing Redis performance, covering command selection, key management, data structures, persistence settings, hardware choices, clustering, and memory fragmentation mitigation to achieve significant speed improvements.
This article explains how to select and implement routing keys for database sharding in a food‑delivery order system, covering supported scenarios, single‑ and multi‑database strategies, hash‑based distribution for both user and merchant data, and practical flow diagrams to ensure balanced and efficient data access.
This article examines the open‑source memory cache Dragonfly, compares its performance and architecture with Redis through detailed benchmark reproductions, discusses the underlying design trade‑offs, and highlights Redis’s continued relevance and future directions in real‑world deployments.
