# Facade Design Pattern — Java Example

**Pattern:** Structural → Facade
**Article:** https://ankurm.com/facade-design-pattern-java/

## What this example shows

A video-conversion subsystem (`VideoFile`, `Codec`, `MPEG4CompressionCodec`, `OggCompressionCodec`, `CodecFactory`, `BitrateReader`, `AudioMixer`) is wrapped behind one class, `VideoConversionFacade`, that exposes a single `convertVideo()` method. Callers never touch the six subsystem classes directly, but they remain public and usable on their own for advanced use cases.

## How to run

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

Requires Java 25.

## Post Section ↔ File Mapping

| Post Section | File(s) |
|---|---|
| The Subsystem (Complex, But Unchanged) — VideoFile | `VideoFile.java` |
| The Subsystem (Complex, But Unchanged) — Codec interface | `Codec.java` |
| The Subsystem (Complex, But Unchanged) — Concrete Codecs | `MPEG4CompressionCodec.java`, `OggCompressionCodec.java` |
| The Subsystem (Complex, But Unchanged) — CodecFactory | `CodecFactory.java` |
| The Subsystem (Complex, But Unchanged) — BitrateReader | `BitrateReader.java` |
| The Subsystem (Complex, But Unchanged) — AudioMixer | `AudioMixer.java` |
| The Facade | `VideoConversionFacade.java` |
| Client Code: One Line | `Main.java` |

Note: the SLF4J `LoggerFactory`, JDBC `DriverManager`, and Spring `JdbcTemplate` snippets under "Facade in the JDK and Real Frameworks" are illustrative only — they are not part of this repository's runnable example.

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