org.springframework.web.bind.annotation.ControllerAdvice Maven / Gradle / Ivy
/*
* Copyright 2002-2018 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
*
* http://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 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, an {@code @ExceptionHandler} will be
* picked on the first advice with a matching exception handler method. For
* model attributes and {@code InitBinder} initialization, {@code @ModelAttribute}
* and {@code @InitBinder} methods will also 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 to a 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 {@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
* @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 e.g.:
* {@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, e.g.: {@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 #value()} for specifying the packages
* to select Controllers to be assisted 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 assisted by the {@code @ControllerAdvice} annotated class.
* @since 4.0
*/
Class[] assignableTypes() default {};
/**
* Array of annotations.
*
Controllers that are annotated with this/one of those annotation(s)
* will be assisted by the {@code @ControllerAdvice} annotated class.
*
Consider creating a special annotation or use a predefined one,
* like {@link RestController @RestController}.
* @since 4.0
*/
Class[] annotations() default {};
}