How is automatic code generation in Dagger for dependency injection performed?

Dagger uses annotations to describe dependencies and components. During compilation, a special annotation processor scans the source code, finds annotations such as @Inject, @Module, and @Component, and based on them generates Java code that implements the dependency graph. This generated code creates objects and links them, ensuring dependency injection without using reflection. This approach improves performance and type safety.

Example:

@Component
interface AppComponent {
    void inject(MyActivity activity);
}

class MyActivity {
    @Inject MyDependency dependency;
}

Dagger will generate a class that creates and provides an instance of MyDependency in MyActivity.