# Decorator Design Pattern — Java Example

**Pattern:** Structural → Decorator
**Article:** https://ankurm.com/decorator-design-pattern-java/

## What this example shows

Builds a text-processing pipeline where behaviours (trim, uppercase, profanity filter) are stacked as wrapper objects around a `PlainTextProcessor`, all sharing the `TextProcessor` interface — the same idea behind `new BufferedReader(new InputStreamReader(...))` in the JDK.

## How to run

```bash
javac decorator/*.java -d out/decorator
java -cp out/decorator decorator.Main
```

Requires Java 25.

## Post Section ↔ File Mapping

| Post Section | File(s) |
|---|---|
| Step 1 — Component Interface | `TextProcessor.java` |
| Step 2 — Concrete Component | `PlainTextProcessor.java` |
| Step 3 — Base Decorator | `TextDecorator.java` |
| Step 4 — Concrete Decorators | `UpperCaseDecorator.java`, `TrimDecorator.java`, `ProfanityFilterDecorator.java` |
| Stacking the Decorators — Order Matters | `Main.java` |

Note: the JDK `InputStream`/`BufferedInputStream`/`GZIPInputStream` snippet under "Decorator in the JDK: I/O Streams" is illustrative only — it is not part of this repository's runnable example.

Article: https://ankurm.com/decorator-design-pattern-java/
All patterns: https://ankurm.com/design-patterns-java/