org.springframework.context.annotation.ConfigurationClassUtils Maven / Gradle / Ivy
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* Copyright 2002-2021 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.io.IOException;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.aop.framework.AopInfrastructureBean;
import org.springframework.beans.factory.annotation.AnnotatedBeanDefinition;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.beans.factory.support.AbstractBeanDefinition;
import org.springframework.context.event.EventListenerFactory;
import org.springframework.core.Conventions;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.core.annotation.Order;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.core.type.classreading.MetadataReader;
import org.springframework.core.type.classreading.MetadataReaderFactory;
import org.springframework.lang.Nullable;
import org.springframework.stereotype.Component;
/**
* Utilities for identifying {@link Configuration} classes.
*
* @author Chris Beams
* @author Juergen Hoeller
* @author Sam Brannen
* @since 3.1
*/
abstract class ConfigurationClassUtils {
public static final String CONFIGURATION_CLASS_FULL = "full";
public static final String CONFIGURATION_CLASS_LITE = "lite";
public static final String CONFIGURATION_CLASS_ATTRIBUTE =
Conventions.getQualifiedAttributeName(ConfigurationClassPostProcessor.class, "configurationClass");
private static final String ORDER_ATTRIBUTE =
Conventions.getQualifiedAttributeName(ConfigurationClassPostProcessor.class, "order");
private static final Log logger = LogFactory.getLog(ConfigurationClassUtils.class);
private static final Set candidateIndicators = new HashSet<>(8);
static {
candidateIndicators.add(Component.class.getName());
candidateIndicators.add(ComponentScan.class.getName());
candidateIndicators.add(Import.class.getName());
candidateIndicators.add(ImportResource.class.getName());
}
/**
* Check whether the given bean definition is a candidate for a configuration class
* (or a nested component class declared within a configuration/component class,
* to be auto-registered as well), and mark it accordingly.
* @param beanDef the bean definition to check
* @param metadataReaderFactory the current factory in use by the caller
* @return whether the candidate qualifies as (any kind of) configuration class
*/
public static boolean checkConfigurationClassCandidate(
BeanDefinition beanDef, MetadataReaderFactory metadataReaderFactory) {
String className = beanDef.getBeanClassName();
if (className == null || beanDef.getFactoryMethodName() != null) {
return false;
}
AnnotationMetadata metadata;
if (beanDef instanceof AnnotatedBeanDefinition &&
className.equals(((AnnotatedBeanDefinition) beanDef).getMetadata().getClassName())) {
// Can reuse the pre-parsed metadata from the given BeanDefinition...
metadata = ((AnnotatedBeanDefinition) beanDef).getMetadata();
}
else if (beanDef instanceof AbstractBeanDefinition && ((AbstractBeanDefinition) beanDef).hasBeanClass()) {
// Check already loaded Class if present...
// since we possibly can't even load the class file for this Class.
Class beanClass = ((AbstractBeanDefinition) beanDef).getBeanClass();
if (BeanFactoryPostProcessor.class.isAssignableFrom(beanClass) ||
BeanPostProcessor.class.isAssignableFrom(beanClass) ||
AopInfrastructureBean.class.isAssignableFrom(beanClass) ||
EventListenerFactory.class.isAssignableFrom(beanClass)) {
return false;
}
metadata = AnnotationMetadata.introspect(beanClass);
}
else {
try {
MetadataReader metadataReader = metadataReaderFactory.getMetadataReader(className);
metadata = metadataReader.getAnnotationMetadata();
}
catch (IOException ex) {
if (logger.isDebugEnabled()) {
logger.debug("Could not find class file for introspecting configuration annotations: " +
className, ex);
}
return false;
}
}
Map config = metadata.getAnnotationAttributes(Configuration.class.getName());
if (config != null && !Boolean.FALSE.equals(config.get("proxyBeanMethods"))) {
beanDef.setAttribute(CONFIGURATION_CLASS_ATTRIBUTE, CONFIGURATION_CLASS_FULL);
}
else if (config != null || isConfigurationCandidate(metadata)) {
beanDef.setAttribute(CONFIGURATION_CLASS_ATTRIBUTE, CONFIGURATION_CLASS_LITE);
}
else {
return false;
}
// It's a full or lite configuration candidate... Let's determine the order value, if any.
Integer order = getOrder(metadata);
if (order != null) {
beanDef.setAttribute(ORDER_ATTRIBUTE, order);
}
return true;
}
/**
* Check the given metadata for a configuration class candidate
* (or nested component class declared within a configuration/component class).
* @param metadata the metadata of the annotated class
* @return {@code true} if the given class is to be registered for
* configuration class processing; {@code false} otherwise
*/
public static boolean isConfigurationCandidate(AnnotationMetadata metadata) {
// Do not consider an interface or an annotation...
if (metadata.isInterface()) {
return false;
}
// Any of the typical annotations found?
for (String indicator : candidateIndicators) {
if (metadata.isAnnotated(indicator)) {
return true;
}
}
// Finally, let's look for @Bean methods...
return hasBeanMethods(metadata);
}
static boolean hasBeanMethods(AnnotationMetadata metadata) {
try {
return metadata.hasAnnotatedMethods(Bean.class.getName());
}
catch (Throwable ex) {
if (logger.isDebugEnabled()) {
logger.debug("Failed to introspect @Bean methods on class [" + metadata.getClassName() + "]: " + ex);
}
return false;
}
}
/**
* Determine the order for the given configuration class metadata.
* @param metadata the metadata of the annotated class
* @return the {@code @Order} annotation value on the configuration class,
* or {@code Ordered.LOWEST_PRECEDENCE} if none declared
* @since 5.0
*/
@Nullable
public static Integer getOrder(AnnotationMetadata metadata) {
Map orderAttributes = metadata.getAnnotationAttributes(Order.class.getName());
return (orderAttributes != null ? ((Integer) orderAttributes.get(AnnotationUtils.VALUE)) : null);
}
/**
* Determine the order for the given configuration class bean definition,
* as set by {@link #checkConfigurationClassCandidate}.
* @param beanDef the bean definition to check
* @return the {@link Order @Order} annotation value on the configuration class,
* or {@link Ordered#LOWEST_PRECEDENCE} if none declared
* @since 4.2
*/
public static int getOrder(BeanDefinition beanDef) {
Integer order = (Integer) beanDef.getAttribute(ORDER_ATTRIBUTE);
return (order != null ? order : Ordered.LOWEST_PRECEDENCE);
}
}