/*
* Copyright 2002-2017 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.stereotype;
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;
Indicate that the annotated element represents a stereotype for the index.
The CandidateComponentsIndex is an alternative to classpath scanning that uses a metadata file generated at compilation time. The index allows retrieving the candidate components (i.e. fully qualified name) based on a stereotype. This annotation instructs the generator to index the element on which the annotated element is present or if it implements or extends from the annotated element. The stereotype is the fully qualified name of the annotated element.
Consider the default Component annotation that is meta-annotated with this annotation. If a component is annotated with Component, an entry for that component will be added to the index using the org.springframework.stereotype.Component stereotype.
This annotation is also honored on meta-annotations. Consider this
custom annotation:
package com.example;
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Indexed
@Service
public @interface PrivilegedService { ... }
If the above annotation is present on a type, it will be indexed with two stereotypes: org.springframework.stereotype.Component and com.example.PrivilegedService. While Service isn't directly annotated with Indexed, it is meta-annotated with Component. It is also possible to index all implementations of a certain interface or all the subclasses of a given class by adding @Indexed on it. Consider this base interface:
package com.example;
@Indexed
public interface AdminService { ... }
Now, consider an implementation of this AdminService somewhere: package com.example.foo;
import com.example.AdminService;
public class ConfigurationAdminService implements AdminService { ... }
Because this class implements an interface that is indexed, it will be automatically included with the com.example.AdminService stereotype. If there are more @Indexed interfaces and/or superclasses in the hierarchy, the class will map to all their stereotypes. Author: Stephane Nicoll Since: 5.0
/**
* Indicate that the annotated element represents a stereotype for the index.
*
* <p>The {@code CandidateComponentsIndex} is an alternative to classpath
* scanning that uses a metadata file generated at compilation time. The
* index allows retrieving the candidate components (i.e. fully qualified
* name) based on a stereotype. This annotation instructs the generator to
* index the element on which the annotated element is present or if it
* implements or extends from the annotated element. The stereotype is the
* fully qualified name of the annotated element.
*
* <p>Consider the default {@link Component} annotation that is meta-annotated
* with this annotation. If a component is annotated with {@link Component},
* an entry for that component will be added to the index using the
* {@code org.springframework.stereotype.Component} stereotype.
*
* <p>This annotation is also honored on meta-annotations. Consider this
* custom annotation:
* <pre class="code">
* package com.example;
*
* @Target(ElementType.TYPE)
* @Retention(RetentionPolicy.RUNTIME)
* @Documented
* @Indexed
* @Service
* public @interface PrivilegedService { ... }
* </pre>
*
* If the above annotation is present on a type, it will be indexed with two
* stereotypes: {@code org.springframework.stereotype.Component} and
* {@code com.example.PrivilegedService}. While {@link Service} isn't directly
* annotated with {@code Indexed}, it is meta-annotated with {@link Component}.
*
* <p>It is also possible to index all implementations of a certain interface or
* all the subclasses of a given class by adding {@code @Indexed} on it.
*
* Consider this base interface:
* <pre class="code">
* package com.example;
*
* @Indexed
* public interface AdminService { ... }
* </pre>
*
* Now, consider an implementation of this {@code AdminService} somewhere:
* <pre class="code">
* package com.example.foo;
*
* import com.example.AdminService;
*
* public class ConfigurationAdminService implements AdminService { ... }
* </pre>
*
* Because this class implements an interface that is indexed, it will be
* automatically included with the {@code com.example.AdminService} stereotype.
* If there are more {@code @Indexed} interfaces and/or superclasses in the
* hierarchy, the class will map to all their stereotypes.
*
* @author Stephane Nicoll
* @since 5.0
*/
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface Indexed {
}