org.springframework.context.annotation.AnnotationBeanNameGenerator Maven / Gradle / Ivy
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* Copyright 2002-2022 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.context.annotation;
import java.util.Collections;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import org.springframework.beans.factory.annotation.AnnotatedBeanDefinition;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.BeanNameGenerator;
import org.springframework.core.annotation.AnnotationAttributes;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.util.StringUtils;
/**
* {@link BeanNameGenerator} implementation for bean classes annotated with the
* {@link org.springframework.stereotype.Component @Component} annotation or
* with another annotation that is itself annotated with {@code @Component} as a
* meta-annotation. For example, Spring's stereotype annotations (such as
* {@link org.springframework.stereotype.Repository @Repository}) are
* themselves annotated with {@code @Component}.
*
* Also supports Jakarta EE's {@link jakarta.annotation.ManagedBean} and
* JSR-330's {@link jakarta.inject.Named} annotations, if available. Note that
* Spring component annotations always override such standard annotations.
*
*
If the annotation's value doesn't indicate a bean name, an appropriate
* name will be built based on the short name of the class (with the first
* letter lower-cased), unless the first two letters are uppercase. For example:
*
*
com.xyz.FooServiceImpl -> fooServiceImpl
* com.xyz.URLFooServiceImpl -> URLFooServiceImpl
*
* @author Juergen Hoeller
* @author Mark Fisher
* @since 2.5
* @see org.springframework.stereotype.Component#value()
* @see org.springframework.stereotype.Repository#value()
* @see org.springframework.stereotype.Service#value()
* @see org.springframework.stereotype.Controller#value()
* @see jakarta.inject.Named#value()
* @see FullyQualifiedAnnotationBeanNameGenerator
*/
public class AnnotationBeanNameGenerator implements BeanNameGenerator {
/**
* A convenient constant for a default {@code AnnotationBeanNameGenerator} instance,
* as used for component scanning purposes.
* @since 5.2
*/
public static final AnnotationBeanNameGenerator INSTANCE = new AnnotationBeanNameGenerator();
private static final String COMPONENT_ANNOTATION_CLASSNAME = "org.springframework.stereotype.Component";
private final Map> metaAnnotationTypesCache = new ConcurrentHashMap<>();
@Override
public String generateBeanName(BeanDefinition definition, BeanDefinitionRegistry registry) {
if (definition instanceof AnnotatedBeanDefinition) {
String beanName = determineBeanNameFromAnnotation((AnnotatedBeanDefinition) definition);
if (StringUtils.hasText(beanName)) {
// Explicit bean name found.
return beanName;
}
}
// Fallback: generate a unique default bean name.
return buildDefaultBeanName(definition, registry);
}
/**
* Derive a bean name from one of the annotations on the class.
* @param annotatedDef the annotation-aware bean definition
* @return the bean name, or {@code null} if none is found
*/
@Nullable
protected String determineBeanNameFromAnnotation(AnnotatedBeanDefinition annotatedDef) {
AnnotationMetadata amd = annotatedDef.getMetadata();
Set types = amd.getAnnotationTypes();
String beanName = null;
for (String type : types) {
AnnotationAttributes attributes = AnnotationConfigUtils.attributesFor(amd, type);
if (attributes != null) {
Set metaTypes = this.metaAnnotationTypesCache.computeIfAbsent(type, key -> {
Set result = amd.getMetaAnnotationTypes(key);
return (result.isEmpty() ? Collections.emptySet() : result);
});
if (isStereotypeWithNameValue(type, metaTypes, attributes)) {
Object value = attributes.get("value");
if (value instanceof String strVal) {
if (StringUtils.hasLength(strVal)) {
if (beanName != null && !strVal.equals(beanName)) {
throw new IllegalStateException("Stereotype annotations suggest inconsistent " +
"component names: '" + beanName + "' versus '" + strVal + "'");
}
beanName = strVal;
}
}
}
}
}
return beanName;
}
/**
* Check whether the given annotation is a stereotype that is allowed
* to suggest a component name through its annotation {@code value()}.
* @param annotationType the name of the annotation class to check
* @param metaAnnotationTypes the names of meta-annotations on the given annotation
* @param attributes the map of attributes for the given annotation
* @return whether the annotation qualifies as a stereotype with component name
*/
protected boolean isStereotypeWithNameValue(String annotationType,
Set metaAnnotationTypes, @Nullable Map attributes) {
boolean isStereotype = annotationType.equals(COMPONENT_ANNOTATION_CLASSNAME) ||
metaAnnotationTypes.contains(COMPONENT_ANNOTATION_CLASSNAME) ||
annotationType.equals("jakarta.annotation.ManagedBean") ||
annotationType.equals("jakarta.inject.Named");
return (isStereotype && attributes != null && attributes.containsKey("value"));
}
/**
* Derive a default bean name from the given bean definition.
* The default implementation delegates to {@link #buildDefaultBeanName(BeanDefinition)}.
* @param definition the bean definition to build a bean name for
* @param registry the registry that the given bean definition is being registered with
* @return the default bean name (never {@code null})
*/
protected String buildDefaultBeanName(BeanDefinition definition, BeanDefinitionRegistry registry) {
return buildDefaultBeanName(definition);
}
/**
* Derive a default bean name from the given bean definition.
*
The default implementation simply builds a decapitalized version
* of the short class name: e.g. "mypackage.MyJdbcDao" → "myJdbcDao".
*
Note that inner classes will thus have names of the form
* "outerClassName.InnerClassName", which because of the period in the
* name may be an issue if you are autowiring by name.
* @param definition the bean definition to build a bean name for
* @return the default bean name (never {@code null})
*/
protected String buildDefaultBeanName(BeanDefinition definition) {
String beanClassName = definition.getBeanClassName();
Assert.state(beanClassName != null, "No bean class name set");
String shortClassName = ClassUtils.getShortName(beanClassName);
return StringUtils.uncapitalizeAsProperty(shortClassName);
}
}