Typically, the `@ExceptionHandler`, `@InitBinder`, and `@ModelAttribute` methods apply within

the `@Controller` class (or class hierarchy) in which they are declared. If you want such

methods to apply more globally (across controllers), you can declare them in a class

marked with `@ControllerAdvice` or `@RestControllerAdvice`.

`@ControllerAdvice` is marked with `@Component`, which means that such classes can be registered

as Spring beans through <<core.adoc#beans-java-instantiating-container-scan, component scanning>>.

`@RestControllerAdvice` is also a meta-annotation marked with both `@ControllerAdvice` and

`@ResponseBody`, which essentially means `@ExceptionHandler` methods are rendered to the

response body through message conversion (versus view resolution or template rendering).

On startup, the infrastructure classes for `@RequestMapping` and `@ExceptionHandler` methods

detect Spring beans of type `@ControllerAdvice` and apply their methods at runtime.

Global `@ExceptionHandler` methods (from a `@ControllerAdvice`) are applied *after* local

ones (from the `@Controller`). By contrast, global `@ModelAttribute` and `@InitBinder`

methods are applied *before* local ones.

By default `@ControllerAdvice` methods apply to every request (that is, all controllers), but

you can narrow that down to a subset of controllers through attributes on the annotation,

as the following example shows:

The preceding selectors are evaluated at runtime and may negatively impact

performance if you use them extensively. See the