Code Smell Detection and Refactoring Impact in Java-Based Applications

Abstract

Code smell detection is important for improving the structural quality, readability, and maintainability of Java-based applications. Java systems often develop long methods, large classes, duplicated logic, feature envy, excessive coupling, and complex inheritance structures as projects grow through repeated updates and maintenance cycles. Traditional quality checks may identify syntax errors and functional defects, but they often miss deeper design-level problems that increase future modification effort. This article focuses on detecting code smells in Java applications and evaluating the impact of refactoring on software quality. The study discusses how smell indicators can be identified through object-oriented metrics, static code analysis, dependency inspection, and before-after comparison of refactored modules. The article concludes that systematic code smell detection and targeted refactoring can reduce technical debt, improve maintainability, simplify testing, and support long-term reliability in Java-based software systems.