Aug 12, 2026 · Fundamentals

Why Mediator, Visitor, and Interpreter Are the Rarest Design Patterns (And When to Avoid Them)

This article examines the three least‑used behavioral design patterns—Mediator, Visitor, and Interpreter—by explaining the problems each solves, showing core implementations with order‑page examples, highlighting their narrow applicability, common pitfalls, and why developers should often steer clear of them.

Design Patternsbehavioralinterpreter

0 likes · 12 min read

Why Mediator, Visitor, and Interpreter Are the Rarest Design Patterns (And When to Avoid Them)

Shepherd Advanced Notes

Jul 1, 2022 · Backend Development

How to Parse Dynamic SQL with Druid: A Practical Guide

This article explains how to use Alibaba's Druid SQL parser to extract and replace dynamic @var parameters in complex SQL statements, detailing the AST structure, visitor pattern, and a complete Java implementation with example code and results.

DruidDynamic SQLJava

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How to Parse Dynamic SQL with Druid: A Practical Guide