Serves as a specialization of {@link Component @Component}, allowing for - * implementation classes to be autodetected through classpath scanning. + *
Classes with {@code @ControllerAdvice} can be declared explicitly as Spring + * beans or auto-detected via classpath scanning. All such beans are sorted via + * {@link org.springframework.core.annotation.AnnotationAwareOrderComparator + * AnnotationAwareOrderComparator}, i.e. based on + * {@link org.springframework.core.annotation.Order @Order} and + * {@link org.springframework.core.Ordered Ordered}, and applied in that order + * at runtime. For handling exceptions the first {@code @ExceptionHandler} to + * match the exception is used. For model attributes and {@code InitBinder} + * initialization, {@code @ModelAttribute} and {@code @InitBinder} methods will + * also follow {@code @ControllerAdvice} order. * - *
It is typically used to define {@link ExceptionHandler @ExceptionHandler}, - * {@link InitBinder @InitBinder}, and {@link ModelAttribute @ModelAttribute} - * methods that apply to all {@link RequestMapping @RequestMapping} methods. - * - *
One of {@link #annotations()}, {@link #basePackageClasses()}, - * {@link #basePackages()} or its alias {@link #value()} - * may be specified to define specific subsets of Controllers - * to assist. When multiple selectors are applied, OR logic is applied - - * meaning selected Controllers should match at least one selector. - * - *
The default behavior (i.e. if used without any selector), - * the {@code @ControllerAdvice} annotated class will - * assist all known Controllers. - * - *
Note that those checks are done at runtime, so adding many attributes and using - * multiple strategies may have negative impacts (complexity, performance). + *
By default the methods in an {@code @ControllerAdvice} apply globally to + * all Controllers. Use selectors {@link #annotations()}, + * {@link #basePackageClasses()}, and {@link #basePackages()} (or its alias + * {@link #value()}) to define a more narrow subset of targeted Controllers. + * If multiple selectors are declared, OR logic is applied, meaning selected + * Controllers should match at least one selector. Note that selector checks + * are performed at runtime and so adding many selectors may negatively impact + * performance and add complexity. * * @author Rossen Stoyanchev * @author Brian Clozel