Suggest an editImprove this articleRefine the answer for “What is the advantage of dynamically adding functionality?”. Your changes go to moderation before they’re published.Approval requiredContentWhat you’re changing🇺🇸EN🇺🇦UAPreviewTitle (EN)Short answer (EN)The advantage of **dynamically adding functionality** lies in the **flexibility and independence of the architecture**: object behavior can be changed **at runtime** without touching their code or creating new classes. **Key point:** a decorator lets you extend the behavior of a stable or third-party class without modifying the source code, simply through a wrapper.Shown above the full answer for quick recall.Answer (EN)ImageThe advantage of **dynamically adding functionality** lies in the **flexibility and independence of the architecture**: object behavior can be changed **at runtime** without touching their code or creating new classes. --- ### 1. **No Need to Change the Source Class** If a class is stable or belongs to an external library, it cannot be edited. A decorator lets you extend its behavior without modifying the source code, simply through a wrapper. --- ### 2. **Combining Behavior on the Fly** You can assemble the functionality you need right at launch: ```java DataSource src = new CompressionDecorator( new EncryptionDecorator( new FileDataSource("file.txt"))); ``` Each "layer" adds its own behavior: encryption, logging, caching, and so on. --- ### 3. **Fewer Classes, More Variations** With inheritance you would have to create dozens of combinations (`EncryptedFile`, `LoggedEncryptedFile`, `CompressedEncryptedFile`...), while with decorators a **few wrappers** are enough, and they can be **freely combined**. --- ### 4. **Supporting SOLID Principles** - **OCP (open/closed):** behavior is extended without changing the code. - **SRP:** each decorator is responsible for one function. --- ### 5. **Testability and Flexibility** You can swap, disable, or add new features without rebuilding the program, which is convenient for tests, configuration, and plugins. --- **Conclusion:** Dynamically adding functionality makes a system **extensible, modular, and safe**, letting you change object behavior **without inheritance and without touching existing code**.For the reviewerNote to the moderator (optional)Visible only to the moderator. Helps review go faster.