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Refine the answer for “How is Factory Method related to the open/closed principle (OCP)?”. Your changes go to moderation before they’re published.

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**Factory Method** directly supports the **open/closed principle (OCP)** because it lets you **extend the system's behavior without changing existing code**.

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### 1. **The essence of OCP**

The principle states:

> *Classes should be open for extension but closed for modification.*
> In other words, when adding new behavior we should **add code**, not **change what already exists**.

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### 2. **How it works in Factory Method**

Instead of hard-coding in the client code which object to create with `new`, we use the abstract method `createProduct()`.
If a new product type appears, we simply:

- create a **new subclass**,
- override the factory method in it.

```java
abstract class Creator {
    abstract Product createProduct();
}

class ConcreteCreatorA extends Creator {
    Product createProduct() { return new ProductA(); }
}

class ConcreteCreatorB extends Creator {
    Product createProduct() { return new ProductB(); }
}
```

At the same time, the base code that uses `createProduct()` **stays unchanged**.

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### 3. **Example**

If you add a new type of transport (for example, `Plane`), you do not need to change the `Logistics` class - it is enough to create `AirLogistics` and override `createTransport()`.

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### 4. **Conclusion**

Factory Method lets you add new object types **without changing the existing logic**, which makes the system **flexible and extensible**, fully in line with the OCP.

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