# Adapter Design Pattern — Java Example

**Pattern:** Structural → Adapter
**Article:** https://ankurm.com/adapter-design-pattern-java/

## What this example shows

Wraps a third-party `StripeClient` (with its own API) behind a `PaymentGateway` interface that your application code expects. The `OrderService` client never touches `StripeClient` directly — it only sees `PaymentGateway`. Swapping payment providers requires changing one line.

## How to run

```bash
# From this folder:
javac adapter/*.java
java adapter.Main
```

Requires Java 25.

## Files

| Post Section | File(s) |
|---|---|
| Step 1 — Define the Target Interface | `PaymentGateway.java` |
| Step 2 — The Adaptee (What You're Wrapping) | `StripeClient.java` |
| Step 3 — The Object Adapter | `StripePaymentAdapter.java` |
| Step 4 — The Client (Knows Nothing About Stripe) | `OrderService.java` |
| Putting It Together: The Main Demo | `Main.java` |
| Object Adapter vs Class Adapter | `StripePaymentClassAdapter.java` |

Note: the `InputStreamReader` JDK-adapter snippet is illustrative only — it is not part of this repository's runnable example.

## See Also

- Full article: https://ankurm.com/adapter-design-pattern-java/
- All design patterns: https://ankurm.com/design-patterns-java/