This article explains how to efficiently insert massive amounts of data (over 100,000 rows) into a MySQL table by comparing plain JDBC single‑row inserts, JDBC batch inserts, MyBatis/MyBatis‑Plus foreach dynamic SQL, and the built‑in MyBatis‑Plus saveBatch method, while highlighting configuration tips and performance results.
This article demonstrates how to integrate Spring Expression Language (SpEL) with custom annotations and AOP in Spring Boot to create a highly flexible, maintainable permission‑checking mechanism that can handle various complex access scenarios without scattering hard‑coded logic throughout the codebase.
The article analyzes unexpected behaviors caused by PageHelper in a Java backend project—such as duplicate registrations, limited query results, and password update errors—by dissecting its source code, ThreadLocal usage, and the importance of proper startPage() and clearPage() handling.
Easy-Query is a Java ORM framework offering strong-typed, database-agnostic CRUD operations, complex SQL generation, multi-table joins, group awareness, and extensive function support, demonstrated through numerous code examples covering queries, joins, subqueries, pagination, and advanced features like enum handling and anonymous type alternatives.
This tutorial explains when to choose XML over JSON, compares their characteristics, and provides step‑by‑step Spring Boot 3.1.7 examples—including Jackson XML configuration, custom root elements, XML view rendering, and JAXB marshalling—to produce XML responses from REST endpoints.
This article presents the 20 most common Spring Boot interview questions, covering fundamentals, features, configuration, performance, security, microservices, and deployment, to help job seekers prepare effectively for Spring Boot related positions in the industry.
Easy-Es is a Java ORM framework built on Elasticsearch's RestHighLevelClient that simplifies search‑engine development, offers Mybatis‑Plus‑like usage, provides configuration and dependency details, and includes complete code examples for creating indexes and performing CRUD operations within Spring Boot applications.
This article explains Java 8's lambda expressions, functional interfaces, and the Stream API, demonstrating how immutable values and functions enable concise data processing through lazy and eager evaluation, with practical code examples covering predicates, consumers, mapping, filtering, grouping, and reduction.
This article provides a comprehensive overview of the major language and runtime enhancements introduced in JDK 12 through JDK 17, covering switch expressions, micro‑benchmarking with JMH, class‑data sharing, garbage‑collector improvements, new String methods, hidden and sealed classes, records, and unified asynchronous logging, all illustrated with code examples.
This article explains how to automate unit conversions for Java DTOs by first using a Map to mark fields and an enum for conversion types, then enhancing the solution with a custom annotation and reflection to make the process more reusable and maintainable.
This article introduces a curated collection of IntelliJ IDEA plugins—including Java Stream Debugger, JClassLib bytecode viewer, Maven Helper, JRebel, and many others—detailing their features, usage instructions, and benefits to enhance Java development productivity and code quality.
This article reviews six practical approaches for scheduling recurring jobs in Java—including custom threads, JDK ScheduledExecutorService, Spring @Scheduled, Quartz, Elastic‑Job, and XXL‑JOB—highlighting their usage, configuration steps, and considerations for clustering and concurrency.
This tutorial walks through creating a complete Spring Boot 2.7 project that integrates Apache Dubbo for RPC, covering environment setup, Maven dependency management, interface definition, provider and consumer implementations, configuration with Nacos, and testing the end‑to‑end service.
The article demonstrates replacing fragile if‑else channel logic with a Strategy pattern and Spring Expression Language, storing parameter mappings in a database so that new payment channels or Excel formats can be added simply by configuring SpEL expressions, achieving a flexible, maintainable, data‑driven solution.
Understanding asynchronous execution in Java can dramatically reduce latency for tasks such as sending SMS, emails, or updating data, and this article walks through eight practical implementations—from raw Threads and Futures to Spring @Async, ApplicationEvent, message queues, ThreadUtil, and Guava ListenableFuture—complete with code samples and best‑practice tips.
This article demonstrates a step‑by‑step method for exporting a list of unknown Java objects to an Excel/CSV file by leveraging reflection to dynamically generate headers and rows, complete with Maven dependencies, utility code, usage examples, and an extensible annotation‑based approach.
This tutorial explains why enterprise applications need multiple data sources, outlines the scenarios such as business isolation, migration, performance and maintainability, and provides a step‑by‑step implementation of dynamic data source routing in Spring Boot using custom context holders, routing classes, annotations, aspects, configuration, and web‑request control.
The article details how a high‑traffic Helios scoring service, originally taking several seconds to return a day’s worth of data, was profiled with Arthas and iteratively optimized through four code revisions, ultimately reducing latency to around 60 ms while exposing key performance pitfalls such as object creation, date formatting, and trivial list operations.
This article provides a comprehensive overview of Java annotations, covering their definition, common applications, classification into standard, meta, and custom annotations, detailed examples of built‑in annotations such as @Override, @Deprecated, @SuppressWarnings, and guidance on creating and using custom annotations with code snippets.
This article explains how to build a robust, thread‑safe local cache for Spring Boot applications by defining cache domain models, abstract managers, a centralized registry, and scheduled refresh tasks, while providing complete Java code examples and best‑practice recommendations.
This article explains how Spring Boot 3's Http Interface feature enables declarative HTTP service calls by defining Java interfaces, covering dependency setup, interface definition, token handling, configuration, controller integration, testing with Postman, and a brief discussion of its WebFlux dependency.
This article demonstrates how to replace heavyweight Spring Security with the lightweight Sa-Token framework by configuring token generation, session management, role and permission retrieval, and global gateway filters in a Spring Cloud micro‑service architecture, including complete code examples and deployment tips.
This article introduces the open‑source Disruptor framework, explains its ring‑buffer architecture, sequencer, wait‑strategy options, and provides complete Java code examples to demonstrate how to build high‑performance producer‑consumer pipelines without locks.
This guide walks through setting up Spring Authorization Server on Spring Boot 3.1 with JDK 17, covering environment setup, required dependencies, custom security filter chains, in‑memory user and client configurations, JWT signing, endpoint settings, consent service, and step‑by‑step testing of the authorization code flow.
This article walks through creating a standardized JSON response structure with a Result enum and wrapper class, demonstrates how to return it from controllers, implements a @ControllerAdvice‑based global exception handler with custom exceptions, and configures Logback for comprehensive logging in Spring Boot applications.
This article explains the limitations of traditional MVC, introduces the four‑layer DDD architecture (Interface, Application, Domain, Infrastructure), discusses the Dependency Inversion Principle, compares package‑level and Maven‑module implementations, and details the roles and conversions of Entity, DO, and DTO models for Java projects.
Switching from Java to Rust can shrink binaries from dozens of megabytes to a few kilobytes, cut memory use and latency dramatically, and provide safer, built‑in concurrency and async support, while Java remains attractive for its low learning curve and massive library ecosystem, prompting developers to wrap Rust crates for Java‑like productivity as they adopt Rust long‑term.
This article provides a comprehensive overview of the Java Virtual Machine, detailing its architecture, class loading process, runtime data areas, and execution engine, including interpreter and JIT compilation, to help readers grasp JVM fundamentals for Java development and interview preparation.
This article examines the design and implementation details of HikariCP—Spring Boot's default JDBC connection pool—explaining how its dual‑pool architecture, FastList collection, custom ConcurrentBag, bytecode‑level optimizations, and efficient connection acquisition and release mechanisms together deliver exceptional performance for Java backend applications.
This article explains Maven's version range syntax, illustrates how open-ended ranges like [2.3.0,) can cause unpredictable dependency versions and build failures, and offers practical solutions such as specifying exact versions or using dependencyManagement to ensure stable, reproducible builds.
This article walks through the common slow Excel‑to‑DB import pattern, shows why it becomes a bottleneck, and presents three progressive optimizations—including caching, asynchronous multi‑threaded reading, and double‑async processing—along with detailed Spring @Async thread‑pool configuration and EasyExcel alternatives, all illustrated with complete Java code samples.
This article explains Java's built‑in serialization drawbacks, introduces the open‑source ChronicleWire library as a high‑performance alternative supporting multiple data formats, and provides step‑by‑step code examples for encoding, decoding, and compatibility handling in real‑world Java applications.
This article introduces Java 8's lambda expressions, functional interfaces, and the Stream API, explaining key concepts such as lazy and eager evaluation, and demonstrates common stream operations like collect, filter, map, flatMap, max/min, count, and reduce with concrete code examples.
This article explains how to obtain a client’s IP address from an HttpServletRequest, convert it to a geographic location using the ip2region library, and provides multiple Java implementation options, Maven dependencies, and performance testing commands for efficient backend IP lookup.
This article demonstrates how to replace heavyweight Spring Security with the lightweight Sa-Token framework by configuring token generation, session storage in Redis, service discovery via Nacos, and permission checks in a Spring Cloud Gateway micro‑service architecture, complete with code examples and deployment settings.
This article explains how Java annotation processors work, why @Transactional requires rollbackFor=Exception.class to roll back checked exceptions, and provides a complete example of a custom processor using auto-service to enforce this Spring transaction configuration.
This article explains Spring’s event mechanism, covering its observer‑based design, benefits such as decoupling and asynchronous handling, standard framework events, and advanced generic event techniques using subclassing or ResolvableTypeProvider to achieve type‑safe, flexible event publishing.
This article provides a detailed explanation of Java’s parent delegation model, covering its definition, visual diagrams, advantages and disadvantages, and a six-step loading process, helping readers understand how class loaders prioritize parent loaders to ensure security and avoid duplicate class loading.
This article explains why upgrading from JDK8 or JDK11 to the long‑term support JDK17 brings significant garbage‑collector performance improvements, new language features, and better framework compatibility, and provides detailed migration steps, Maven and SpringBoot configuration changes, and troubleshooting tips.
Maven’s version ranges let you specify acceptable artifact versions, but open‑ended ranges like [2.3.0,) cause Maven to fetch the newest matching release, leading to nondeterministic builds and potential incompatibilities, so you should pin exact versions and use dependencyManagement for consistent, stable builds.
This article demonstrates how to store, create, update, and delete scheduled tasks in a SpringBoot application by leveraging ThreadPoolTaskScheduler, covering task configuration, utility classes, Cron expressions, and practical testing with full code examples.
This article demonstrates how to efficiently build department and regional hierarchical trees in Java by fetching all records in a single database query, using Stream API, Lambda expressions, in‑memory grouping, Redis caching and RocketMQ for asynchronous updates, achieving sub‑second response times even with tens of thousands of nodes.
Fury is a JIT‑compiled, zero‑copy, multi‑language serialization framework that delivers up to 170× speed improvements over traditional serializers, supports Java, Python, C++, Go, JavaScript, Scala and Rust, and has recently been donated to the Apache Software Foundation after a successful open‑source journey.
This article walks through the challenges of environment‑specific data isolation in a Java project, explains why adding an env column to every table is impractical, and presents a clean solution using a MyBatis interceptor that rewrites SQL and custom annotations to control filtering, ensuring safe, maintainable code across pre‑release, gray, and production environments.
This article explains why retry mechanisms are essential for unstable third‑party API calls, introduces Spring Retry, demonstrates how to configure synchronous and asynchronous retries, handle exception inclusion/exclusion, integrate circuit‑breaker fallback with Hystrix, and provides performance testing guidance, all with practical code examples.
A Java program that creates two alarm threads and a single shared object ends up in a deadlock because each thread holds its own lock while waiting for the other's lock, illustrating the pitfalls of careless synchronized usage.
This guide explains how to implement API rate limiting in SpringBoot 2.7.16 using custom annotations, AspectJ, and the high‑performance Caffeine cache, covering cache configuration, eviction policies, statistics, and practical code examples for annotation definition, aspect logic, and controller usage.
This tutorial explains how to switch between multiple databases in a Spring Boot application by implementing ThreadLocal and AbstractRoutingDataSource, covering code implementation, configuration, testing, annotation-based switching, and dynamic addition of data sources with detailed examples and practical guidance.
This article analyzes the CPU‑heavy routing and load‑balancing modules of Dubbo in a large‑scale microservice cluster, identifies O(n) traversal as the root cause, and presents a step‑by‑step redesign—including disabling unused routers, caching route results with epoch validation, BitMap‑based intersection, and grouped routing—that reduces CPU usage by up to 27% and doubles TPS when provider instances exceed 2,000.
This article presents a curated collection of essential open‑source Java libraries—including logging, JSON parsing, testing, utility, HTTP, XML, Excel, bytecode, database connection pooling, messaging, PDF, date‑time, collections, email, HTML parsing, encryption, embedded databases, JDBC debugging, serialization, networking, and more—to help developers boost productivity and write better code.
This article compiles 28 practical IntelliJ IDEA shortcuts, settings tweaks, and plugin recommendations that help Java developers quickly navigate code history, manage memory, customize keymaps, automate imports, visualize dependencies, and improve overall coding efficiency.
This article explains how to combine Domain‑Driven Design's four‑layer architecture with a microservice‑oriented application SDK, introduces the D3boot lightweight framework and its modular base components, and shows how the approach simplifies building SaaS and PaaS systems while keeping code reusable and maintainable.
This article examines the inner workings of Java's java.util.UUID class, detailing how UUID.randomUUID() generates version‑4 UUIDs using SecureRandom, the bitwise adjustments for version and variant fields, and the constructor logic that assembles the final 128‑bit identifier.
This article walks through the complete process of implementing a custom login authentication in Spring Boot, including custom authentication filters, success/failure handlers, a token stored in Redis, role‑based URL security, and detailed configuration of Spring Security headers and session handling.
This article provides a comprehensive guide to Java development fundamentals, covering naming conventions, comment quality, class and method definitions, object design patterns, and performance considerations such as immutable types, sealed classes, and the Valhalla project, with practical code examples and best‑practice recommendations.
This article explains why rate limiting is essential for high‑concurrency systems, defines rate limiting, introduces four common algorithms (fixed‑window, sliding‑window, leaky‑bucket, token‑bucket), provides Java code examples for each, compares their advantages and disadvantages, and shows practical usage with Guava's RateLimiter and AOP annotations.
An in‑depth comparison of popular Java in‑process caching solutions—Guava, Caffeine, and Ehcache—covers their expiration policies, capacity limits, eviction strategies, monitoring features, performance optimizations, and ideal use cases, helping developers select the most suitable cache for their applications.
This article covers Java backend architecture fundamentals, including front‑end/back‑end separation, Maven configuration, distributed lock implementations with Redis and Zookeeper, session handling in distributed systems, database locking strategies, and useful code snippets for common patterns.
This article explains what optimistic locking is, why it matters for concurrent Java applications, and details four implementation methods—version numbers, timestamps, CAS, and sequence numbers—along with their principles, usage scenarios, and practical considerations for high‑performance, distributed systems.
This guide walks through Spring 6’s new capabilities—including Java 17 baseline, Jakarta namespace migration, HTTP interface proxies with @HttpExchange, WebClient integration via JDK HttpClient, internationalized ProblemDetail handling, the RestClient API, and executing asynchronous tasks on virtual threads—all demonstrated with concise code examples.
This article explains how to implement unified, user‑friendly exception handling for Feign‑based service calls in a Spring distributed architecture by customizing ErrorDecoder, defining result objects, and using global @ControllerAdvice to return clear error codes and messages to front‑end users.
This article explains how to prevent API abuse by using a Spring Interceptor combined with Redis to count requests per IP and URI, demonstrates step‑by‑step code implementations, discusses custom annotations, mapping rules, time‑window challenges, path‑parameter handling, and real‑IP extraction for robust backend rate limiting.
This article explains the concept of distributed tracing, outlines its underlying principles in Java, details step‑by‑step implementation using popular SDKs, and describes common application scenarios such as performance monitoring, fault diagnosis, complex event handling, traffic analysis, and system optimization.
This article walks through the problem of sharing a single database across pre‑release, gray, and production environments, explains why adding an env column to dozens of tables is error‑prone, and demonstrates a MyBatis interceptor‑based solution with custom annotations that isolates data while preserving backward compatibility.
The article analyzes the inventory oversell problem caused by concurrent purchase requests and presents four backend solutions—including a Redis distributed lock, MySQL row lock, optimistic locking with version fields, and conditional SQL updates—illustrated with Java code and SQL examples to ensure data consistency.
Starting from a basic Java method that maps a sale‑type string to an integer, the article incrementally refactors the code by applying null‑safe utilities, constants, static methods, ternary/Optional expressions, enums with lookup maps, a combined relation enum, and finally a Strategy pattern with a container, illustrating how each step improves safety, readability, extensibility, and testability.
This article explains how Redisson's DelayedQueue implements a distributed delayed message queue, covering basic usage, internal data structures, the overall processing flow, and detailed code analysis of sending, receiving, and initializing delayed messages in Java.
This tutorial demonstrates how to use Spring WebFlux’s reactive streaming to create a ChatGPT‑like typing effect, covering backend setup, SSE integration, frontend Axios handling, and a comparison between Flux and traditional Server‑Sent Events.
This article explains the limitations of java.util.concurrent.Phaser for large‑scale asynchronous tasks, presents a custom FunPhaser implementation that removes the party‑count ceiling, details its design, API, and usage examples, and compares it with the original Phaser approach.
This article presents a comprehensive collection of practical IntelliJ IDEA tips for Java developers, covering code history viewing, memory settings, Eclipse keymap, case‑insensitive suggestions, disabling inspections, documentation templates, method separators, multi‑line tabs, bracket navigation, code completion, fuzzy search, class preview, call hierarchy, Maven dependency visualization, SSH tool, and more to significantly boost coding efficiency.
This article explains the concepts, architecture, and practical usage of Liteflow, a lightweight Java rule engine that integrates with Spring Boot, supports various rule file formats, multiple component types, data contexts, and configuration options for building complex workflow processes in backend applications.
This guide demonstrates how to retrieve command‑line arguments, use JSON‑encoded properties, load external configuration files, encrypt values, parse YAML, generate random properties, handle internationalization, customize the banner, and configure the application context in Spring Boot 3.0.9, providing code examples for each feature.
This article walks through eight practical ways to implement retry mechanisms for remote API calls in Java, covering simple loops, recursion, Apache HttpClient settings, Spring Retry, Resilience4j, custom utilities, asynchronous thread‑pool retries, and message‑queue based retries, while highlighting trade‑offs and best‑practice guidelines.
Kafka, an Apache‑developed distributed publish/subscribe messaging system, provides reliable, high‑throughput real‑time data streaming with producers, consumers, brokers, streams, and connectors, and the article explains its core concepts, architecture, advantages, deployment methods, use cases, and includes Java code examples for producers and consumers.
This article explains the concept of delayed tasks, compares them with scheduled tasks, and evaluates multiple implementation strategies—including database polling, JDK DelayQueue, Netty HashedWheelTimer, Redis ZSET, Redis keyspace notifications, and RabbitMQ delayed queues—highlighting their advantages and drawbacks for order‑processing scenarios.
This article introduces EasyExcel, a Java library that simplifies high‑performance Excel read/write operations, explains its core concepts, provides practical code examples for reading, writing, and filling Excel files, and discusses performance‑optimizing techniques and important usage considerations.
This article walks Java and Spring Boot developers through installing Camunda, configuring dependencies, setting up the database, creating a simple BPMN process with user and service tasks, and testing the workflow via the Camunda web interface, providing code snippets and screenshots for each step.
This article explains Java enums, their underlying class inheritance, key Enum methods, practical code examples, and advanced uses such as implementing singletons and strategy patterns, helping developers master enums for robust backend development.
This article explains two API rate‑limiting strategies—fixed‑window using Redis keys and sliding‑window using Redis sorted sets—detailing their principles, drawbacks, and providing complete Java implementations with Lua scripts, AOP annotations, and Redis configuration to enforce request limits.
This article explores Spring 5.3.23’s core utility classes—including ID generators, concurrent LRU cache, concurrency throttling, StopWatch timing, digest calculation, method invocation, reflection helpers, route matching, collection utilities, and placeholder parsing—providing code examples, usage guidelines, and best practices to boost backend development efficiency.
When Maven’s archetype plugin hangs during project generation, you can resolve it by specifying archetypeCatalog=internal or local as a command-line or VM option, placing a downloaded archetype-catalog.xml in ~/.m2, or configuring a domestic mirror in settings.xml, after which generation completes in seconds.
This article presents a comprehensive design and implementation of a customizable data permission framework for Java backend applications, detailing the requirements, rule table structure, strategy pattern handling, custom annotations, AOP integration, and practical examples with full source code snippets.
This guide walks you through setting up Spring Cloud Task on Spring Boot 2.7 with Spring Cloud 2021, covering environment requirements, Maven dependencies, configuration files, task annotations, ApplicationRunner implementation, database schema, task listeners, and advanced task configuration options.
This article explains Spring's seven transaction propagation modes, how they affect nested @Transactional method calls, and the resulting commit or rollback behavior in various scenarios, providing clear examples and diagrams for each propagation type.
This article describes how ZhaiZhai implements log desensitization for personal data protection using a reusable Java utility class, JSON serializer customizations with Jackson, and an annotation‑processing tool that automatically generates masked toString methods, while also discussing operational challenges and future plans.
The article explains why iterating an ArrayList with forEach and removing elements causes a ConcurrentModificationException, analyzes the underlying fail‑fast iterator behavior, and presents three correct ways—using Iterator.remove, removeIf, and collecting then removing—to delete elements safely.
The January 2024 TIOBE Index reveals C# winning the 2023 Programming Language of the Year award, highlights Java’s market‑share loss and pricing controversy, showcases the rise of Kotlin, Fortran and COBOL, and offers expert predictions on which languages may break into the Top 20 next year.
Compileflow is a lightweight, high‑performance Java workflow engine that converts BPMN files into compiled code, offering seamless integration, visual process design, and extensive plugin support, with quick‑start instructions, code examples, and a concise summary of its advantages and current limitations.
This article compares Java's native record feature with the Lombok library, showing how records can reduce boilerplate code, outlining scenarios where records can replace Lombok, and discussing the limitations of each approach for clean and maintainable backend development.
The 2023 TIOBE Index crowned C# as the top programming language, highlighting its rapid growth over Java, the impact of Java's new subscription pricing, and the broader shifts in language popularity that could shape development trends through 2024.
This article walks Java developers from Java 8 to Java 17 through the most widely‑adopted language enhancements—including var, switch expressions, text blocks, records, pattern‑matching, sealed classes, and helpful NullPointerExceptions—explaining each feature with concise descriptions and code snippets.
The article explains Java's PreparedStatement interface, highlighting its performance, security, and batch processing benefits, and provides a complete example of inserting multiple user records efficiently, while also discussing practical considerations such as batch size, transaction handling, error management, and optimization tips.
This article introduces PowerJob, explains its key features such as lock‑free scheduling, multiple execution modes, and workflow support, and provides step‑by‑step instructions for installing via Docker or JAR, configuring databases, setting up server and client projects, and creating and managing scheduled tasks in Java.
This article provides a step‑by‑step guide to implementing custom login authentication in a Spring Boot application, including Redis‑backed session storage, token handling, security headers, and fine‑grained role‑based URL permission checks using custom filters and handlers.
This article explains how to use Spring Boot Security for authentication and improve performance by caching user details in Redis, covering dependency setup, security configuration, Redis integration, testing endpoints, and optimization tips for a robust backend authentication solution.
This article demonstrates step‑by‑step how to prevent API abuse in a Spring MVC application by using an Interceptor combined with Redis for counting requests, customizing limits per endpoint through annotations and reflection, handling mapping rules, path‑parameter challenges, and obtaining the real client IP.
This article compares delayed tasks with scheduled tasks and presents six practical Java solutions—database polling with Quartz, JDK DelayQueue, Netty's HashedWheelTimer, Redis ZSET, Redis key‑space notifications, and RabbitMQ delayed queues—detailing their implementations, advantages, and drawbacks for handling order‑timeout scenarios.
This article explains how Android's LayoutInflater converts XML layout files into View objects, demonstrates the various ways to obtain and use a LayoutInflater, details the overloads of the inflate method, and shows how to customize view creation with Factory and Factory2 interfaces, including practical code examples.
This guide explains how to use Spring Integration's LockRegistry for distributed locking, covering both database‑based and Redis‑based implementations, complete with Maven dependencies, configuration snippets, bean definitions, and comprehensive test cases to ensure reliable synchronization across multiple nodes.
This article explains why manual property copying in Java is inefficient, compares several runtime bean‑copy utilities, and demonstrates how MapStruct provides a compile‑time, type‑safe, high‑performance solution for shallow and deep object mapping, including handling of collections and ignored fields.
