This article explains how SpringBoot interceptors work, demonstrates custom interceptor implementation, shows how misuse of ThreadLocal can cause memory leaks and OOM errors, and provides a fix by moving cleanup logic to afterCompletion, complete with code samples and performance screenshots.
This article introduces Liteflow, a lightweight yet powerful Java rule engine built on Spring Boot, explains its architecture, usage patterns, component types, EL rule files, data context handling, configuration options, and demonstrates a real‑world e‑commerce workflow, while also containing promotional material for related services.
This article explains PHP's ceil() function, shows its syntax, and provides three code examples demonstrating how to round floating‑point numbers and integers upward, illustrating the returned smallest integer greater than or equal to the given value.
This article explains critical pitfalls, proper shutdown handling, event loss during startup, suitable business scenarios, reliability guarantees, and best‑practice patterns for employing Spring Event in high‑traffic backend systems, providing concrete code examples and operational recommendations.
This article explains RocketMQ’s batch processing concepts, walks through the early batch model, the index‑build pipeline refactor, the BatchCQ and AutoBatch models, and presents benchmark results that show dramatic throughput gains and lower latency compared to Kafka.
This article explains the challenges of loading historical chat messages in an instant‑messaging app and demonstrates why traditional offset pagination fails, then introduces cursor‑based pagination with SQL examples and best‑practice guidelines for reliable incremental loading.
This article introduces PHP's array_slice() function, explains its parameters and syntax, and provides three practical code examples demonstrating how to extract subsets of an array, preserve keys, and use it for pagination.
This article explores the concept of traffic hijacking, compares front‑end and back‑end interception methods, and provides practical proxy‑based implementations for fetch, XMLHttpRequest, and ReadableStream to achieve seamless request and response manipulation in a unified authentication system.
This article explains how Nginx processes regular expressions and location directives, details the syntax and priority of different location prefixes, and provides concrete configuration examples with code snippets and diagrams to help developers correctly match request URIs.
This article walks through six common Go interview mistakes—incorrect function brace placement, map initialization without make, unexported struct fields for JSON, ineffective slice iteration, array versus slice parameter passing, and variable shadowing with :=—explaining each issue and providing the correct code examples.
This article explains the PHP array() function, demonstrates how to create both indexed and associative arrays with clear examples, outlines important usage notes, and provides sample code for various array types to help developers master array creation in PHP.
This article explains PHP's in_array() function, covering its basic syntax, parameters, return values, and demonstrates both normal and strict comparisons with clear code examples, helping developers efficiently check for values within arrays.
This article describes a complete solution for creating a PDF contract electronic signature system using Vue for the front‑end rendering, pdfjs‑dist to extract predefined form fields, and pdf‑lib on the back‑end to generate a signed PDF, covering field extraction, coordinate conversion, canvas overlay, and server‑side PDF manipulation.
This article explains the challenges of multiple product logins, reviews traditional session mechanisms, discusses session sharing solutions in clustered environments, and presents a CAS‑based single sign‑on implementation with Java code examples, highlighting differences between CAS and OAuth2 for secure authentication.
The article explains interface‑level failures in business systems and presents four mitigation strategies—degradation, circuit breaking, rate limiting, and queuing—detailing their principles, implementation methods, and algorithmic choices such as fixed and sliding windows, token bucket and leaky bucket.
This article explains the history, key technologies, benefits, drawbacks, and practical recommendations for adopting a frontend‑backend separation architecture, especially for startups seeking scalable, maintainable, and efficient web applications.
A detailed post‑mortem of a three‑time service outage reveals how hidden bugs, frequent FullGC, a saturated connection pool, and an unindexed slow SQL query crippled a Spring Boot backend, and shows the step‑by‑step troubleshooting, temporary fixes, and lasting improvements applied.
The interview discusses various routing and blocking strategies of the xxl-job distributed task scheduling framework, explains how it addresses task overlap, idempotency issues, and provides practical solutions such as single‑machine execution, locking mechanisms, and using a business date to avoid date‑related problems.
This article analyzes typical thread‑pool misuses that caused a production outage, explains why tasks may slow down under load, and provides concrete recommendations such as pagination, timeout handling, proper pool sizing, avoiding shared pools, ThreadLocal cleanup, and cautious use of parallel streams.
This article explains the PHP array_filter() function, its parameters, and demonstrates how to filter numeric arrays and associative arrays with practical code examples, helping developers efficiently remove unwanted elements based on custom callback logic.
This article explains how the PHP file() function reads a file's contents into an array, details its syntax and parameters, demonstrates basic and flag‑based usage with code examples, and highlights important behavior such as line handling and newline removal.
Node.js v22.6.0 introduces the experimental --experimental-strip-types flag, enabling developers to execute TypeScript files directly, but it only strips type annotations at runtime and imposes several usage constraints such as mandatory type‑only imports and explicit file extensions.
This article outlines the business background, detailed payment workflow, associated product and coupon management, and practical implementation tips for designing a robust payment system, covering process decomposition, sequence diagrams, data structures, transaction handling, and key technical considerations such as transaction management, locking, and settlement accuracy.
This article explains how PHP's array_pop function removes and returns the last element of an array, shows its syntax, provides a complete code example with expected output, and summarizes its usefulness for handling array data in backend development.
This article explains PHP's array_flip() function, detailing its syntax, behavior with duplicate values, and practical uses such as reversing associative arrays and looking up keys by value, illustrated with clear code examples and output demonstrations.
This article recounts a small startup’s journey from selecting uni‑app for cross‑platform mobile development and egg.js for the backend, through mid‑project adjustments, hiring challenges, and practical team‑management advice, highlighting lessons to avoid common pitfalls.
This article explains how to use PHP's urldecode function to decode URL-encoded parameters and full URLs, provides practical code examples, demonstrates the relationship with urlencode, and highlights best practices for handling special characters in web development.
This article introduces PHP 7.4's Foreign Function Interface (FFI), explains how to enable it, demonstrates basic usage and advanced examples for calling C functions, discusses performance considerations, security best practices, troubleshooting, and future directions for PHP developers.
This article demonstrates how to transform overly complex Spring Boot controllers—filled with repetitive validation, try‑catch blocks, and business logic—into clean, maintainable implementations by applying @Valid annotations, streamlined validation, and a centralized global exception handler.
This article explains PHP's array_fill() function, detailing its purpose, parameters, return behavior, and provides clear code examples—including simple and two‑dimensional array fills—to help developers quickly master array creation and population in backend development.
Introduced in PHP 7.3, the array_key_first() function returns the first key of an array or null for an empty array, and this article explains its syntax, demonstrates usage with code examples, and discusses practical scenarios such as retrieving the first key and checking if an array is empty.
This guide explains how to integrate JSON Schema validation into a Spring Boot application, covering dependency setup, schema definition, bean configuration, service implementation, controller handling, and testing with curl examples to ensure JSON payloads conform to the defined rules.
This guide walks through initializing a Spring Boot project, handling IDE licensing hurdles, ensuring compatible Spring Cloud, Spring Boot, and Kafka versions, leveraging Maven for dependency management, and integrating essential utilities like global exception handling, logging, CORS, Swagger, and helpful development tools.
This article explains how to quickly test MyBatis SQL statements by bypassing the Spring container, using a minimal MyBatis configuration, adding support for PageHelper pagination and MyBatis‑Plus plugins, and provides code examples and a plugin recommendation for efficient backend development.
This article explains how to implement product purchase quantity limits in a PHP‑based online store by designing a stock field in the database, updating product detail, cart, and order pages, using Ajax for dynamic updates, and handling inventory adjustments during order processing to improve user experience and operational efficiency.
This article explains PHP's array_replace_recursive() function, detailing its syntax, recursive merging behavior, example usage with code, output interpretation, important considerations, and compares it with array_merge_recursive() for effective backend array handling in PHP development.
This article details the design, architecture, and Java implementation of a WebSocket‑based backend that enables real‑time, multi‑player quiz battles, covering entity definitions, message handling, matchmaking logic, error handling, game flow, and supporting utilities such as Redis‑based state management.
This article explains how to quickly develop an AI‑native application using Spring AI, covering core features such as chat models, prompt templates, function calling, structured output, image generation, embedding, vector stores, and Retrieval‑Augmented Generation (RAG), and provides end‑to‑end Java code examples for building a simple AI‑driven service.
The article demonstrates how to transform overly complex Spring Boot controllers—filled with repetitive validation and business logic—into clean, maintainable code by using @Valid annotations, concise validation rules, and a centralized exception handler, effectively halving the code size and improving readability.
This article explains how to leverage Java 8's @FunctionalInterface, including Supplier, Consumer, Runnable, and Function, to eliminate repetitive if…else branches, handle exceptions, and simplify branch logic with concise lambda‑based utilities.
This article explains the PHP str_replace function, its syntax, and demonstrates three practical examples—simple replacement, replacing multiple words with an array, and deleting characters—showing the resulting output and highlighting additional options available in the official documentation.
This article explains how to refactor Spring MVC controller layers by introducing a unified response wrapper, handling String conversion issues with ResponseBodyAdvice, applying JSR‑303 validation for request parameters, creating custom validation annotations, and implementing custom exceptions with a global exception handler to produce clean, maintainable backend code.
This article analyzes how JavaScript’s rich functionality, expanding ecosystem, and single‑language workflow have reshaped web development, outlines the essential front‑end and back‑end skills for full‑stack developers, and explores the career advantages and future trends such as WebAssembly.
This article describes a business approval scenario where a company name entered by a business user must be checked for duplicates, and explains how to implement fuzzy matching using MySQL RegExp, tokenization with IKAnalyzer, and Java service code to extract, preprocess, match, and rank results by relevance.
This article explains how Spring 3.0's pure annotation development simplifies bean configuration, demonstrates defining beans with @Component, managing bean scopes, performing various injection techniques, reading properties files, and integrating MyBatis, providing complete code examples and best‑practice tips for backend Java developers.
This article explains PHP's array_unique() function, covering its definition, parameters, implementation logic, practical usage examples, and performance enhancements using array_flip(), providing clear code snippets and detailed explanations to efficiently remove duplicate values from arrays and improve execution speed in real-world applications.
The article explains PHP's is_file() function, how it determines file existence, proper usage with absolute or relative paths, differences from is_dir(), handling of symlinks, and provides practical code examples for checking files before reading them, emphasizing its importance for backend developers.
This article outlines comprehensive backend API design guidelines, covering parameter validation, extensibility, idempotency, logging, thread‑pool isolation, third‑party error handling, asynchronous processing, parallel queries, rate limiting, security, lock granularity, and strategies to avoid long‑running transactions.
This article walks through the author's practical research on integrating WebSocket in Spring Boot, detailing step‑by‑step configurations for Javax, WebMVC, and WebFlux, comparing their APIs, highlighting pitfalls, and providing concrete code snippets and cold‑knowledge tips for both server and client implementations.
This guide walks through Nginx’s four primary load‑balancing methods—round‑robin, weighted, IP‑hash, and least‑connections—explaining their principles, when to use each, and providing complete configuration examples and code snippets to help you distribute traffic efficiently across multiple backend servers.
This article introduces a Spring‑based asynchronous processing SDK that leverages annotations, transaction event listeners, Kafka, XXL‑Job, and a dedicated database to achieve non‑blocking execution, fault tolerance, and eventual consistency while preserving transaction integrity and providing a clear configuration and usage guide.
This article explains why combining Lombok's @Data and @Builder annotations can remove the automatically generated no‑args constructor, demonstrates the resulting compilation errors, and provides two practical solutions using @Tolerate or a combination of @RequiredArgsConstructor and @NoArgsConstructor, while also describing Lombok's annotation‑processing mechanism.
This article explains PHP's array_fill() function, detailing its purpose, three parameters, return behavior, and provides clear code examples for both one‑dimensional and two‑dimensional array creation.
This article analyzes the complexities of payment system design, covering business background, modular process breakdown, sequence diagrams for pre‑payment, payment integration, post‑payment stages, and detailed structural design, while also highlighting related business components and practical implementation tips.
This tutorial explains how Spring's pure annotation mode replaces XML bean definitions, covers component scanning, bean scopes, dependency injection techniques, property loading, and demonstrates seamless integration with MyBatis for streamlined backend development.
This article explains how PHP closure functions can be used to encapsulate reusable code blocks, demonstrates practical examples including simple arithmetic, data processing callbacks, and integration with object‑oriented programming to improve code reuse and maintainability.
This article explains PHP's in_array() function, detailing its syntax, parameters, return values, and demonstrates basic usage, strict mode comparison, and searching within multidimensional arrays through clear code examples to help developers efficiently check element existence in arrays.
This article explains how the Rust cfg_if crate simplifies conditional compilation by providing a macro that replaces nested #[cfg] attributes with clear if‑else or match structures, shows step‑by‑step usage, advanced patterns, and compares cfg_if to raw #[cfg] for readability and maintainability.
This article introduces Easy‑Query, a Java ORM that provides a strongly‑typed, chainable query syntax covering basic CRUD, pagination, joins, sub‑queries, native SQL fragments, group‑by, custom VO mapping and high‑performance encryption, illustrated with extensive code examples and usage notes.
This article outlines comprehensive best‑practice guidelines for designing robust, secure, and maintainable backend services—covering API path conventions, request handling, parameter design, error codes, dependency management, monitoring, degradation strategies, legacy service handling, encryption, access control, and tamper‑proof mechanisms, with practical code examples.
This article explains PHP’s array_values() function, showing how it returns a new array with reindexed numeric keys, works with both indexed and associative arrays, provides code examples, and highlights that the returned array is a copy, not a reference to the original.
This article explains PHP’s built-in array_unique() function, detailing its syntax, behavior, and flags, and demonstrates how to remove duplicate values from arrays with practical code examples and real-world use cases such as data cleaning, input validation, and aggregation.
This article explains how the PHP curl_multi_getcontent() function works, demonstrates its usage together with curl_multi_init() and curl_multi_exec() for concurrent requests, provides a complete code example, and highlights important considerations when fetching results from multiple cURL handles.
This course teaches learners with basic front‑end skills how to combine the uniapp framework and ThinkPHP backend to build high‑performance, cross‑platform mobile applications, covering data modeling, token authentication, API design, middleware, pagination, and deployment.
This guide demonstrates how parameterized Python decorators can streamline repetitive tasks in API automation testing—handling login tokens, retries, environment selection, data‑driven tests, logging, performance monitoring, permission checks, mock responses, cleanup, and test tagging—reducing code duplication and improving maintainability.
During a Monday incident where the backend service became unavailable three times, the author details step-by-step investigations—checking frontend responses, container status, JVM and thread pool metrics, and database connection pool usage—ultimately identifying a slow, unindexed SQL query that exhausted connections, and describes the remediation and lessons learned.
This article demonstrates how to quickly build and benchmark a Spring Boot 2.x application as a native binary, compares its startup time, memory usage, and request throughput with equivalent implementations in Go and Rust, and concludes that AOT‑processed Java offers impressive performance despite longer compilation times.
The article explains why a complex billing module in a settlement system needs optimization, describes the problems of monolithic code and tangled responsibilities, and demonstrates a refactor using the responsibility‑chain pattern with clear, pluggable nodes, accompanied by Java code examples and best‑practice recommendations.
This article explains how the extract and validate features of HttpRunner can be used to retrieve data from HTTP responses and assert response correctness, providing multiple practical code examples for token handling, pagination, response time checks, and custom validation functions in API testing.
This article explains how to achieve seamless code updates for SpringBoot applications by allowing two instances to share the same port, detailing the underlying Tomcat embedding mechanism, DispatcherServlet handling, and providing a complete Java implementation with step‑by‑step instructions and test results.
This article explains how to use PHP's is_callable() function to determine whether a given function, method, class constructor, or static method can be invoked, demonstrates the syntax with a complete example, and shows the expected output for both callable and non‑callable identifiers.
The article details the design, core technical solutions, high‑availability architecture, performance optimizations, and open capabilities of Buffalo, JD.com’s distributed DAG‑based job scheduling platform that supports massive task volumes, complex dependencies, and flexible resource management.
This article explains the key changes in Spring Boot 3, outlines the new OAuth2 components, and provides a detailed design for secure microservice authentication and authorization using Spring Authorization Server, JWT, API Gateway, and client applications, complete with architecture diagrams and implementation steps.
This article explains how to design a unified API response format in backend development, covering JSON structure, status‑code conventions, controller refactoring, annotation‑based response wrapping, and practical implementation steps to achieve clean, maintainable, and user‑friendly API outputs.
This article explains how to correctly use PHP's session_start function, demonstrates setting session lifetimes with session_set_cookie_params, and shows how to destroy sessions using session_destroy, providing clear code examples for each step.
This article explains Java's built‑in Service Provider Interface (SPI) mechanism, demonstrates how to create interfaces, implementations, and configuration files, shows testing with ServiceLoader, and compares it to Spring's SPI implementation using spring.factories, including code examples and analysis of their advantages and limitations.
This article presents a collection of reusable Python utility interfaces—including data validation, HTTP request handling, file read/write, JSON parsing, date‑time formatting, symmetric encryption, SQLite persistence, image resizing, exception handling, and configuration loading—each illustrated with concise code examples to improve code readability and testability.
This article explains the background, features, installation steps, core concepts, library definitions, rule set creation (wizard and script), decision tables, practical usage scenarios, and provides complete Java and configuration code examples for integrating the URule rule engine in a Spring Boot backend application.
This article explains the PHP in_array() function, detailing its syntax, parameters, and three practical examples that demonstrate value searching, strict type checking, and retrieving keys, helping developers improve array handling efficiency and code readability.
This article explains the benefits of creating a custom PHP framework—such as meeting specific needs, learning core concepts, ensuring maintainability, optimizing performance, improving usability, and enhancing security—and provides a detailed chapter and section outline for a tutorial covering MVC, routing, design patterns, configuration, and database handling.
This article analyzes the problems of scattered property configuration in SpringBoot projects, designs a database table to store configuration items, implements a configuration loader that injects database values into the Spring environment, and demonstrates testing and best‑practice considerations for a robust backend configuration solution.
This article explains how to use PHP's mysqli_query function to perform MySQL operations such as SELECT, INSERT, UPDATE, and DELETE, including a full example that creates a connection, runs a query, processes results, and closes the connection.
This article explains how PHP's str_replace function works, shows its syntax, and provides three practical examples—simple replacement, multiple replacements using an array, and character deletion—demonstrating how to manipulate strings efficiently in backend development.
This article explains how to convert a list of Java User objects into a Map using Stream's toMap collector, handling duplicate keys and null values with merge functions and Optional, and compares alternative approaches including manual HashMap population.
This article introduces MyBatis-Mate, an official MyBatis‑Plus extension offering enterprise‑level capabilities such as dictionary binding, field encryption, data masking, dynamic DDL maintenance, sharding, multi‑datasource switching, performance logging, and data permission control, with detailed Spring Boot integration examples.
The article details a real‑world backend engineering project where a loan repayment service is refactored to use table sharding with ShardingSphere, covering design decisions, table naming, sharding algorithms, historical data migration, dynamic switches, transaction management, code examples, and practical pitfalls.
This article explains how the PHP strlen() function works to determine the length of a string, provides a clear example with code, discusses the difference between byte and character counts, and highlights important considerations regarding character encoding when using strlen in backend development.
This article explains PHP's rename() function, detailing its syntax, required source and target parameters, boolean return values, practical code examples for renaming files and directories, and important considerations such as permissions and error handling.
This article presents ten carefully crafted PHP project concepts—from building a custom MVC framework and implementing data import/export to creating QR code generators and event management tools—each designed to showcase backend expertise and enhance a developer's professional portfolio.
This article reviews outdated Java technologies—JSP, Struts, Hibernate, and others—explaining why they are no longer essential for modern backend development and offering clear guidance on which skills to prioritize or abandon.
This article explains how to use PHP's built-in is_bool() function to determine whether a variable holds a boolean value, provides clear code examples with four different variables, shows the expected output, and discusses why certain values are not considered booleans.
This guide explains how to install the Imagick extension for PHP, create an Imagick object, load an image, adjust its brightness, saturation, and hue using modulateImage, and then save or output the modified image, providing a complete example code snippet.
This article explains the PHP is_string() function, its simple syntax, and demonstrates with example code how to check variables like $name, $age, and $city to determine whether they are strings, including best practices for input validation.
This article explains why excessive if‑else statements hurt Spring Boot code and presents six practical techniques—including strategy pattern, enums, polymorphism, lambda expressions, command pattern, and guard clauses—along with complete Java examples to make your backend more modular, readable, and maintainable.
This article provides a step‑by‑step guide on using Elasticsearch’s Painless scripting language to create, index, and manipulate array‑type fields, covering basic operations like length and element access, as well as advanced aggregations, filtering, and weighted calculations, while highlighting performance considerations.
This article presents a detailed overview of Spring's utility classes, covering assertion helpers, object and collection utilities, file and resource I/O methods, as well as reflection and AOP tools, complete with code examples for each feature.
This article explains PHP's fgetc() function for reading single characters from files or user input, demonstrates opening files with fopen(), shows loop-based character reading, and provides complete code examples for both file and interactive input scenarios.
This article explains PHP’s is_numeric() function, shows 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 trailing decimal points.
This tutorial explains how to construct XML data in Python, set the appropriate Content-Type header, send it via a POST request using the requests library, and parse the XML response, providing complete example code for developers working with web APIs.
This comprehensive guide walks backend developers through practical techniques—such as proper indexing, SQL refactoring, parallel remote calls, asynchronous processing, caching layers, sharding, and monitoring—to diagnose and dramatically improve API response times and overall system throughput.
