<!-- Page: https://rustic-game-engine.pages.dev/docs/scripting/java/complete-behavior -->

# Complete behavior

[Back to Java](https://rustic-game-engine.pages.dev/markdown/scripting/java.md).

Complete the [setup and attachment steps](https://rustic-game-engine.pages.dev/markdown/scripting/java/setup-and-attachment.md), then paste this behavior into the attached script.

```java
class RusticBehavior extends Rustic {
    public static void main(String[] args) throws Exception {
        run((callback, dt) -> {
            if (callback.equals("on_start")) rustic.log("info", "Behavior started");
            if (callback.equals("fixed_update") && rustic.key("KeyW").held) {
                double[] p = rustic.get_translation();
                rustic.set_translation(p[0], p[1], p[2] + dt);
            }
        });
    }
}
```

The SDK is staged automatically beside the source in an engine temporary directory.
You do not install a package, copy the SDK into your game, or write a process loop.
**Programming > Open Programming Workspace** also writes editor support files under
`.rustic/generated/programming`. Regenerate those files after upgrading Rustic.
Edit your behavior source, not generated SDK files. Run through Rustic Play so the
engine can supply the API and callback state.