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.
This article explains step‑by‑step how to compare, delete, reset, and force‑push unwanted Git commits using both simple manual comparison and the more elegant reset options in IntelliJ IDEA, while also noting the limitations of complex changes and including promotional offers for related services.
This article walks through building a Python-based appointment elevator control system, covering platform setup, independent elevator design with detailed class implementations, a task‑oriented group‑control algorithm, and provides complete source code and diagrams for simulation and scheduling.
This guide explains how to use Spring's @Configurable annotation and the AnnotationBeanConfigurerAspect to inject dependencies into objects created with new, covering environment setup, Maven configuration, AspectJ weaving, and advanced options like autowiring, constructor injection, and dependency checks.
This article presents a real‑world case study of a high‑concurrency data‑processing interface whose response time was reduced from 30 seconds to under one second by diagnosing SQL bottlenecks, refactoring MyBatis code, applying PostgreSQL array aggregation, and introducing a Caffeine cache, while also discussing the limits of relational databases and promoting related AI services.
A market study reveals that rising Oracle Java subscription costs are driving many users to migrate to OpenJDK, and this guide explains the reasons behind the shift and provides step‑by‑step instructions for removing Oracle JDK and installing OpenJDK.
This guide explains how to use regular‑expression path variables, property placeholders, class‑level parameters, and suffix‑based content negotiation in SpringBoot 3.2.5, providing code examples, configuration tips, and practical request illustrations for flexible URL routing.
This article explains the fundamentals and key characteristics of Remote Procedure Call (RPC), outlines common use cases and popular frameworks, and then walks through the design and implementation of a simple custom RPC system—including a bespoke binary protocol, client‑side proxy generation, serialization, Netty‑based encoding/decoding, server‑side request handling, and result delivery—using Java and Netty.
The article presents a concise mind‑map of essential Linux performance tools and a flexible troubleshooting workflow, guiding backend developers through CPU, memory, disk, and network issues by using utilities such as top, oprofile, slabtop, iotop, netstat, and strace to quickly pinpoint and resolve bottlenecks.
This article dives deep into Uber's fx dependency‑injection framework for Go, explaining advanced constructs such as fx.Invoke, fx.Supply, fx.Populate, fx.Annotated, fx.In, fx.Out, fx.Module, fx.WithLogger and fx.As, and provides complete code examples that illustrate how to manage lifecycles, inject static values, differentiate multiple implementations, and customize logging in production‑grade applications.
To prevent IO saturation during Elasticsearch ILM hot‑to‑cold migrations, the article recommends batching migrations, fine‑tuning max_bytes_per_sec, upgrading cold‑node storage and adding hot nodes, and automating monitoring with scripts that pause or resume ILM based on real‑time utilization thresholds.
PHP 7.3 introduced the array_key_first() function, which returns the first key of an array or null if empty; this article explains its syntax, demonstrates usage with examples, compares it to older approaches, and outlines scenarios such as retrieving the first key and checking for empty arrays.
This article explains the fundamentals of Remote Procedure Call (RPC), its role in distributed systems, the architecture and workflow of RPC frameworks, and compares popular implementations such as Thrift, Dubbo, and Spring Cloud with other communication styles like REST, SOAP, and SOA.
This article explains how to build an online user counting feature by leveraging Redis sorted sets (zset) in Java, covering user identification, the core Redis commands (zadd, zrangeByScore, zremrangeByScore, zrem), code examples, and periodic cleanup logic.
This article explains how PHP's array_slice() function works, detailing its parameters, basic syntax, and providing three clear code examples that demonstrate extracting subsets of arrays, preserving keys, and using the function for pagination.
This article explains the core principles of Java Stream, covering its three main characteristics, pipeline construction, intermediate and terminal operations with code examples, and how lazy execution and sink generation produce results only when a terminal operation is invoked.
This article explains the core concepts of dependency injection, introduces Uber’s Fx framework for Go, and provides step‑by‑step code examples that demonstrate how to register providers, manage application lifecycles, and use hooks for start‑up and shutdown logic.
This article explains why Hutool switched its package names to org.dromara.hutool in version 6.0, details the major refactorings, performance optimizations, and API changes, and provides practical migration advice and code examples for developers upgrading from 5.x to 6.0.
This guide walks you through installing, configuring, and using Egg‑Sequelize in Egg.js, explains core ORM features, demonstrates model definition and CRUD operations, and covers advanced topics such as complex queries, transactions, validation, migrations, associations, and common pitfalls to avoid.
This guide explains why e‑commerce platforms need a high‑performance search engine, introduces Elasticsearch fundamentals, compares it with traditional engines, and provides step‑by‑step PHP code for installing, configuring, indexing, and querying data, complete with practical examples and best‑practice tips.
This article provides a comprehensive guide to Viper, a powerful Go configuration library, covering its core advantages, step‑by‑step basic usage—including installation, defaults, file handling, environment variables, command‑line flags, remote providers—and advanced techniques such as sub‑tree reading, custom decoding, and managing multiple Viper instances.
The team built a custom video‑transcoding core atop FFmpeg libraries, replacing the command‑line tool with modular controllers, pipelines, and parallel tasks that dynamically adapt resolution, frame‑rate, and SEI handling for both low‑latency live streams and high‑throughput VOD, improving scalability and maintainability.
The article explains why a backend team moved from PHP to Go for high‑concurrency live‑streaming services and demonstrates two Go concurrency patterns—sync.WaitGroup and errgroup—with code examples and common pitfalls.
This article explores how various unique identifier schemes—random UUIDs, sequential numbers, hierarchical paths, and distributed ID generators—are applied across programming languages, file systems, databases, and networks, and explains when and how to enforce uniqueness using pre‑validation, database constraints, or distributed locks such as Redis and Zookeeper, while also linking these mechanisms to CAS‑based concurrency control.
Domain-Driven Design (DDD) is a software development methodology that bridges business and technology by defining clear domain models, improving communication, code quality, and handling complexity through layered architecture, with concrete C# examples of entities, value objects, aggregates, and domain services.
This tutorial explains the STOMP protocol, its frame structure, and how Spring Boot 3 integrates STOMP over WebSocket, providing step‑by‑step code examples for enabling STOMP, sending and receiving messages, handling headers, asynchronous processing, exception handling, and simple publish‑subscribe without a controller.
This article introduces lua‑resty‑redis, explains its non‑blocking I/O model, outlines typical use cases, details installation via OPM, provides step‑by‑step Lua code for basic operations and transactions, and demonstrates testing with curl, helping developers build high‑performance OpenResty services.
This article explains how to install the CheckStyle plugin in IntelliJ IDEA, configure it with custom rule sets such as Alibaba's, run checks on Java code, and troubleshoot common issues like missing annotations, spacing, naming, formatting, and import order, while also noting related promotional content.
This article explains the syntax and parameters of PHP’s array_multisort() function, demonstrates its usage with a concrete example that sorts student names, ages, and scores, and shows the resulting output while highlighting important flags and usage tips.
This article introduces Domain-Driven Design (DDD), explains its core concepts, benefits, and the four-layered DDD architecture—including UI, Application, Domain, and Infrastructure layers—while also offering resources for deeper study and interview preparation.
