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Refine the answer for “How does "Proxy" differ from "Decorator"?”. Your changes go to moderation before they’re published.

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**Proxy** and **Decorator** look similar on the surface - both "wrap" an object and implement the same interface.
But their **goals and purposes differ**.

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### 1. **Purpose**

- **Proxy** **controls access** to an object.
→ decides *when*, *how*, and *whether* the real object can be called.
- **Decorator** **extends the behavior** of an object.
→ adds new functionality *on top of* the existing one.

---

### 2. **Context of Use**

| Situation | Proxy | Decorator |
|---|---|---|
| The object is heavy or remote | Lazy loading, cache | Not intended for this |
| Need to add new behavior (logging, encryption) | Possible, but not the main goal | The main goal |
| Access control / security | Yes | No |
| The client should think it is working with the "real object" | Mandatory | Not always |

---

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

**Proxy (access control):**

```java
class SecuredFileProxy implements FileAccess {
    private RealFile realFile;
    private String userRole;

public void read() {
        if (userRole.equals("admin")) realFile.read();
        else System.out.println("Access denied");
    }
}
```

**Decorator (behavior extension):**

```java
class LoggingFileDecorator implements FileAccess {
    private FileAccess wrappee;
    public void read() {
        System.out.println("Reading file...");
        wrappee.read();
    }
}
```

---

### 4. **Transparency**

- **Proxy** aims to be *unnoticeable*: the client should not know it is working with an intermediary.
- **Decorator** is a *deliberate wrapper*: the client knows that new behavior has been added.

---

### 5. **Analogy**

- **Proxy** is like a **guard at the door**, deciding who gets in.
- **Decorator** is like a **designer**, decorating a room without changing its foundation.

---

### **Conclusion**

| Criterion | Proxy | Decorator |
|---|---|---|
| Main purpose | Access control | Behavior extension |
| Transparency for the client | Full | Partial |
| Type of behavior | Controlling | Additive |
| Example | Lazy loading, protection, cache | Logging, encryption, formatting |

**Summary:**
**Proxy** protects or controls,
**Decorator** adds and decorates.

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