org.springframework.web.bind.annotation.ControllerAdvice Maven / Gradle / Ivy
/*
* Copyright 2002-2019 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.web.bind.annotation;
import java.lang.annotation.Annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import org.springframework.core.annotation.AliasFor;
import org.springframework.stereotype.Component;
/**
* Specialization of {@link Component @Component} for classes that declare
* {@link ExceptionHandler @ExceptionHandler}, {@link InitBinder @InitBinder}, or
* {@link ModelAttribute @ModelAttribute} methods to be shared across
* multiple {@code @Controller} classes.
*
* Classes annotated with {@code @ControllerAdvice} can be declared explicitly
* as Spring beans or auto-detected via classpath scanning. All such beans are
* sorted based on {@link org.springframework.core.Ordered Ordered} semantics or
* {@link org.springframework.core.annotation.Order @Order} /
* {@link javax.annotation.Priority @Priority} declarations, with {@code Ordered}
* semantics taking precedence over {@code @Order} / {@code @Priority} declarations.
* {@code @ControllerAdvice} beans are then applied in that order at runtime.
* Note, however, that {@code @ControllerAdvice} beans that implement
* {@link org.springframework.core.PriorityOrdered PriorityOrdered} are not
* given priority over {@code @ControllerAdvice} beans that implement {@code Ordered}.
* In addition, {@code Ordered} is not honored for scoped {@code @ControllerAdvice}
* beans — for example if such a bean has been configured as a request-scoped
* or session-scoped bean. For handling exceptions, an {@code @ExceptionHandler}
* will be picked on the first advice with a matching exception handler method. For
* model attributes and data binding initialization, {@code @ModelAttribute} and
* {@code @InitBinder} methods will follow {@code @ControllerAdvice} order.
*
*
Note: For {@code @ExceptionHandler} methods, a root exception match will be
* preferred to just matching a cause of the current exception, among the handler
* methods of a particular advice bean. However, a cause match on a higher-priority
* advice will still be preferred over any match (whether root or cause level)
* on a lower-priority advice bean. As a consequence, please declare your primary
* root exception mappings on a prioritized advice bean with a corresponding order.
*
*
By default, the methods in an {@code @ControllerAdvice} apply globally to
* all controllers. Use selectors such as {@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, boolean {@code OR} logic is applied, meaning
* selected controllers should match at least one selector. Note that selector checks
* are performed at runtime, so adding many selectors may negatively impact
* performance and add complexity.
*
* @author Rossen Stoyanchev
* @author Brian Clozel
* @author Sam Brannen
* @since 3.2
* @see org.springframework.stereotype.Controller
* @see RestControllerAdvice
*/
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Component
public @interface ControllerAdvice {
/**
* Alias for the {@link #basePackages} attribute.
*
Allows for more concise annotation declarations — for example,
* {@code @ControllerAdvice("org.my.pkg")} is equivalent to
* {@code @ControllerAdvice(basePackages = "org.my.pkg")}.
* @since 4.0
* @see #basePackages
*/
@AliasFor("basePackages")
String[] value() default {};
/**
* Array of base packages.
*
Controllers that belong to those base packages or sub-packages thereof
* will be included — for example,
* {@code @ControllerAdvice(basePackages = "org.my.pkg")} or
* {@code @ControllerAdvice(basePackages = {"org.my.pkg", "org.my.other.pkg"})}.
*
{@link #value} is an alias for this attribute, simply allowing for
* more concise use of the annotation.
*
Also consider using {@link #basePackageClasses} as a type-safe
* alternative to String-based package names.
* @since 4.0
*/
@AliasFor("value")
String[] basePackages() default {};
/**
* Type-safe alternative to {@link #basePackages} for specifying the packages
* in which to select controllers to be advised by the {@code @ControllerAdvice}
* annotated class.
*
Consider creating a special no-op marker class or interface in each package
* that serves no purpose other than being referenced by this attribute.
* @since 4.0
*/
Class[] basePackageClasses() default {};
/**
* Array of classes.
*
Controllers that are assignable to at least one of the given types
* will be advised by the {@code @ControllerAdvice} annotated class.
* @since 4.0
*/
Class[] assignableTypes() default {};
/**
* Array of annotation types.
*
Controllers that are annotated with at least one of the supplied annotation
* types will be advised by the {@code @ControllerAdvice} annotated class.
*
Consider creating a custom composed annotation or use a predefined one,
* like {@link RestController @RestController}.
* @since 4.0
*/
Class[] annotations() default {};
}