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**Decorator** and **Wrapper** are almost the same in structure:
in both cases an object is **wrapped by another object** that **intercepts calls** and **adds extra behavior**.

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### 1. **The Shared Idea**

- Both patterns use **composition**: they hold a reference to the "wrapped" object internally.
- Both implement the **same interface** as the original, so the client does not notice a difference.
- Both delegate calls to the original object, adding something "on top".

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### 2. **An Example of the Shared Approach**

```java
class Wrapper implements Service {
    private Service wrappee;
    public Wrapper(Service s) { this.wrappee = s; }

public void execute() {
        System.out.println("Before");
        wrappee.execute();
        System.out.println("After");
    }
}
```

This structure can be called either a **decorator** or a **wrapper**: the difference is only in the purpose.

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### 3. **Difference in Emphasis**

| Criterion | Decorator | Wrapper |
|---|---|---|
| Purpose | Extend functionality | Isolate, simplify, or hide details |
| Used in | Design patterns | General programming |
| Semantics | "Add behavior" | "Wrap to control access, adapt, or protect" |

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### 4. **An Example of the Difference**

- **Decorator:** adds logging, encryption, caching.
- **Wrapper:** hides the complexity of an API or a data format (for example, `HttpResponseWrapper`).

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**Conclusion:**
A **decorator is a special case of a wrapper**, specialized in **adding new behavior**,
while a **wrapper** is a more general term for any layer
that **intercepts and delegates calls** to the underlying object.

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