Resources and tutorials for programmers' advanced learning journey. Advanced tracks in Java, Python, and C#. Blog: https://blog.csdn.net/badao_liumang_qizhi
This article explains the WKB binary format, its storage advantages in MySQL and PostgreSQL, and provides step‑by‑step Java code using JTS's GeometryFactory, WKBWriter, and WKBReader to write a Point to WKB, convert it to a hex string, and read it back into a geometry object.
This article walks through how to use the Singleton pattern together with SpringBoot's ScheduledExecutorService to build a reusable asynchronous task manager, recreate Ruoyi's login‑log recording logic, and verify the non‑blocking behavior with a concrete test case.
This guide shows how to integrate the lightweight LiteFlow rule engine into a Spring Boot application, split complex business logic into reusable components, configure rule files, and use various component types—including switch, condition, and parameterized components—to achieve dynamic orchestration, hot‑reloading, and high scalability.
This article explains the Visitor design pattern, illustrates its structure, and provides a complete Java implementation that lets HR and finance departments process full‑time and part‑time employee data in an OA system without modifying existing classes.
The article shows how to replace bulky if‑else logic in Spring Boot by using the strategy pattern together with a factory that autowires all Strategy implementations into a Map, explains the @Autowired semantics for collections, and provides concrete code examples.
This article walks through using the Apache POI and POI‑TL libraries to render Word (.docx) files from custom templates, covering version compatibility, template syntax, data model definitions, and step‑by‑step code examples for text, images, tables, and charts.
This guide walks through reading local or network images in Java, creating a Graphics2D canvas, and applying either a red semi‑transparent text watermark or a scaled image watermark at pixel‑specified coordinates before saving the result as a PNG file.
This article demonstrates how to use Jsoup to fetch and parse HTML content from a web page, extract specific table data via CSS selectors, map the data to Java objects, and efficiently write the results to an Excel file with EasyExcel, highlighting memory advantages over POI.
This guide shows how to integrate the open‑source Tesseract OCR engine into a Spring Boot application using the Tess4J Java wrapper, covering Chinese language data setup, Maven dependency configuration, bean creation, service implementation, and a unit test to verify image text extraction.
This article explains how to configure Spring Boot's built‑in ThreadPoolTaskExecutor, customize its core parameters, and use it together with Java 8 CompletableFuture to run asynchronous tasks, including a performance comparison with a synchronous implementation.
