org.springframework.boot.autoconfigure.web.servlet.ConditionalOnMissingFilterBean Maven / Gradle / Ivy
/*
* Copyright 2012-2019 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.boot.autoconfigure.web.servlet;
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 javax.servlet.Filter;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Conditional;
import org.springframework.core.annotation.AliasFor;
/**
* {@link Conditional @Conditional} that only matches when no {@link Filter} beans of the
* specified type are contained in the {@link BeanFactory}. This condition will detect
* both directly registered {@link Filter} beans as well as those registered via a
* {@link FilterRegistrationBean}.
*
* When placed on a {@code @Bean} method, the bean class defaults to the return type of
* the factory method or the type of the {@link Filter} if the bean is a
* {@link FilterRegistrationBean}:
*
*
* @Configuration
* public class MyAutoConfiguration {
*
* @ConditionalOnMissingFilterBean
* @Bean
* public MyFilter myFilter() {
* ...
* }
*
* }
*
* In the sample above the condition will match if no bean of type {@code MyFilter} or
* {@code FilterRegistrationBean} is already contained in the
* {@link BeanFactory}.
*
* @author Phillip Webb
* @since 2.1.0
*/
@Target({ ElementType.TYPE, ElementType.METHOD })
@Retention(RetentionPolicy.RUNTIME)
@Documented
@ConditionalOnMissingBean(parameterizedContainer = FilterRegistrationBean.class)
public @interface ConditionalOnMissingFilterBean {
/**
* The filter bean type that must not be present.
* @return the bean type
*/
@AliasFor(annotation = ConditionalOnMissingBean.class)
Class[] value() default {};
}