org.springframework.context.annotation.ConfigurationClassPostProcessor Maven / Gradle / Ivy
/*
* Copyright 2002-2016 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.context.annotation;
import java.beans.PropertyDescriptor;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashSet;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
import java.util.List;
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.autoproxy.AutoProxyUtils;
import org.springframework.beans.PropertyValues;
import org.springframework.beans.factory.BeanClassLoaderAware;
import org.springframework.beans.factory.BeanDefinitionStoreException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanDefinitionHolder;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessorAdapter;
import org.springframework.beans.factory.config.SingletonBeanRegistry;
import org.springframework.beans.factory.parsing.FailFastProblemReporter;
import org.springframework.beans.factory.parsing.PassThroughSourceExtractor;
import org.springframework.beans.factory.parsing.ProblemReporter;
import org.springframework.beans.factory.parsing.SourceExtractor;
import org.springframework.beans.factory.support.AbstractBeanDefinition;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.BeanDefinitionRegistryPostProcessor;
import org.springframework.beans.factory.support.BeanNameGenerator;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.context.EnvironmentAware;
import org.springframework.context.ResourceLoaderAware;
import org.springframework.context.annotation.ConfigurationClassEnhancer.EnhancedConfiguration;
import org.springframework.core.Ordered;
import org.springframework.core.PriorityOrdered;
import org.springframework.core.env.Environment;
import org.springframework.core.io.DefaultResourceLoader;
import org.springframework.core.io.ResourceLoader;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.core.type.classreading.CachingMetadataReaderFactory;
import org.springframework.core.type.classreading.MetadataReaderFactory;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import static org.springframework.context.annotation.AnnotationConfigUtils.*;
/**
* {@link BeanFactoryPostProcessor} used for bootstrapping processing of
* {@link Configuration @Configuration} classes.
*
* Registered by default when using {@code
This post processor is {@link Ordered#HIGHEST_PRECEDENCE} as it is important
* that any {@link Bean} methods declared in Configuration classes have their
* respective bean definitions registered before any other BeanFactoryPostProcessor
* executes.
*
* @author Chris Beams
* @author Juergen Hoeller
* @author Phillip Webb
* @since 3.0
*/
public class ConfigurationClassPostProcessor implements BeanDefinitionRegistryPostProcessor,
PriorityOrdered, ResourceLoaderAware, BeanClassLoaderAware, EnvironmentAware {
private static final String IMPORT_AWARE_PROCESSOR_BEAN_NAME =
ConfigurationClassPostProcessor.class.getName() + ".importAwareProcessor";
private static final String IMPORT_REGISTRY_BEAN_NAME =
ConfigurationClassPostProcessor.class.getName() + ".importRegistry";
private static final String ENHANCED_CONFIGURATION_PROCESSOR_BEAN_NAME =
ConfigurationClassPostProcessor.class.getName() + ".enhancedConfigurationProcessor";
private final Log logger = LogFactory.getLog(getClass());
private SourceExtractor sourceExtractor = new PassThroughSourceExtractor();
private ProblemReporter problemReporter = new FailFastProblemReporter();
private Environment environment;
private ResourceLoader resourceLoader = new DefaultResourceLoader();
private ClassLoader beanClassLoader = ClassUtils.getDefaultClassLoader();
private MetadataReaderFactory metadataReaderFactory = new CachingMetadataReaderFactory();
private boolean setMetadataReaderFactoryCalled = false;
private final Set registriesPostProcessed = new HashSet();
private final Set factoriesPostProcessed = new HashSet();
private ConfigurationClassBeanDefinitionReader reader;
private boolean localBeanNameGeneratorSet = false;
/* using short class names as default bean names */
private BeanNameGenerator componentScanBeanNameGenerator = new AnnotationBeanNameGenerator();
/* using fully qualified class names as default bean names */
private BeanNameGenerator importBeanNameGenerator = new AnnotationBeanNameGenerator() {
@Override
protected String buildDefaultBeanName(BeanDefinition definition) {
return definition.getBeanClassName();
}
};
@Override
public int getOrder() {
return Ordered.LOWEST_PRECEDENCE; // within PriorityOrdered
}
/**
* Set the {@link SourceExtractor} to use for generated bean definitions
* that correspond to {@link Bean} factory methods.
*/
public void setSourceExtractor(SourceExtractor sourceExtractor) {
this.sourceExtractor = (sourceExtractor != null ? sourceExtractor : new PassThroughSourceExtractor());
}
/**
* Set the {@link ProblemReporter} to use.
* Used to register any problems detected with {@link Configuration} or {@link Bean}
* declarations. For instance, an @Bean method marked as {@code final} is illegal
* and would be reported as a problem. Defaults to {@link FailFastProblemReporter}.
*/
public void setProblemReporter(ProblemReporter problemReporter) {
this.problemReporter = (problemReporter != null ? problemReporter : new FailFastProblemReporter());
}
/**
* Set the {@link MetadataReaderFactory} to use.
*
Default is a {@link CachingMetadataReaderFactory} for the specified
* {@linkplain #setBeanClassLoader bean class loader}.
*/
public void setMetadataReaderFactory(MetadataReaderFactory metadataReaderFactory) {
Assert.notNull(metadataReaderFactory, "MetadataReaderFactory must not be null");
this.metadataReaderFactory = metadataReaderFactory;
this.setMetadataReaderFactoryCalled = true;
}
/**
* Set the {@link BeanNameGenerator} to be used when triggering component scanning
* from {@link Configuration} classes and when registering {@link Import}'ed
* configuration classes. The default is a standard {@link AnnotationBeanNameGenerator}
* for scanned components (compatible with the default in {@link ClassPathBeanDefinitionScanner})
* and a variant thereof for imported configuration classes (using unique fully-qualified
* class names instead of standard component overriding).
*
Note that this strategy does not apply to {@link Bean} methods.
*
This setter is typically only appropriate when configuring the post-processor as
* a standalone bean definition in XML, e.g. not using the dedicated
* {@code AnnotationConfig*} application contexts or the {@code
* } element. Any bean name generator specified against
* the application context will take precedence over any value set here.
* @since 3.1.1
* @see AnnotationConfigApplicationContext#setBeanNameGenerator(BeanNameGenerator)
* @see AnnotationConfigUtils#CONFIGURATION_BEAN_NAME_GENERATOR
*/
public void setBeanNameGenerator(BeanNameGenerator beanNameGenerator) {
Assert.notNull(beanNameGenerator, "BeanNameGenerator must not be null");
this.localBeanNameGeneratorSet = true;
this.componentScanBeanNameGenerator = beanNameGenerator;
this.importBeanNameGenerator = beanNameGenerator;
}
@Override
public void setEnvironment(Environment environment) {
Assert.notNull(environment, "Environment must not be null");
this.environment = environment;
}
@Override
public void setResourceLoader(ResourceLoader resourceLoader) {
Assert.notNull(resourceLoader, "ResourceLoader must not be null");
this.resourceLoader = resourceLoader;
}
@Override
public void setBeanClassLoader(ClassLoader beanClassLoader) {
this.beanClassLoader = beanClassLoader;
if (!this.setMetadataReaderFactoryCalled) {
this.metadataReaderFactory = new CachingMetadataReaderFactory(beanClassLoader);
}
}
/**
* Derive further bean definitions from the configuration classes in the registry.
*/
@Override
public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) {
RootBeanDefinition iabpp = new RootBeanDefinition(ImportAwareBeanPostProcessor.class);
iabpp.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
registry.registerBeanDefinition(IMPORT_AWARE_PROCESSOR_BEAN_NAME, iabpp);
RootBeanDefinition ecbpp = new RootBeanDefinition(EnhancedConfigurationBeanPostProcessor.class);
ecbpp.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
registry.registerBeanDefinition(ENHANCED_CONFIGURATION_PROCESSOR_BEAN_NAME, ecbpp);
int registryId = System.identityHashCode(registry);
if (this.registriesPostProcessed.contains(registryId)) {
throw new IllegalStateException(
"postProcessBeanDefinitionRegistry already called on this post-processor against " + registry);
}
if (this.factoriesPostProcessed.contains(registryId)) {
throw new IllegalStateException(
"postProcessBeanFactory already called on this post-processor against " + registry);
}
this.registriesPostProcessed.add(registryId);
processConfigBeanDefinitions(registry);
}
/**
* Prepare the Configuration classes for servicing bean requests at runtime
* by replacing them with CGLIB-enhanced subclasses.
*/
@Override
public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) {
int factoryId = System.identityHashCode(beanFactory);
if (this.factoriesPostProcessed.contains(factoryId)) {
throw new IllegalStateException(
"postProcessBeanFactory already called on this post-processor against " + beanFactory);
}
this.factoriesPostProcessed.add(factoryId);
if (!this.registriesPostProcessed.contains(factoryId)) {
// BeanDefinitionRegistryPostProcessor hook apparently not supported...
// Simply call processConfigurationClasses lazily at this point then.
processConfigBeanDefinitions((BeanDefinitionRegistry) beanFactory);
}
enhanceConfigurationClasses(beanFactory);
}
/**
* Build and validate a configuration model based on the registry of
* {@link Configuration} classes.
*/
public void processConfigBeanDefinitions(BeanDefinitionRegistry registry) {
List configCandidates = new ArrayList();
String[] candidateNames = registry.getBeanDefinitionNames();
for (String beanName : candidateNames) {
BeanDefinition beanDef = registry.getBeanDefinition(beanName);
if (ConfigurationClassUtils.isFullConfigurationClass(beanDef) ||
ConfigurationClassUtils.isLiteConfigurationClass(beanDef)) {
if (logger.isDebugEnabled()) {
logger.debug("Bean definition has already been processed as a configuration class: " + beanDef);
}
}
else if (ConfigurationClassUtils.checkConfigurationClassCandidate(beanDef, this.metadataReaderFactory)) {
configCandidates.add(new BeanDefinitionHolder(beanDef, beanName));
}
}
// Return immediately if no @Configuration classes were found
if (configCandidates.isEmpty()) {
return;
}
// Sort by previously determined @Order value, if applicable
Collections.sort(configCandidates, new Comparator() {
@Override
public int compare(BeanDefinitionHolder bd1, BeanDefinitionHolder bd2) {
int i1 = ConfigurationClassUtils.getOrder(bd1.getBeanDefinition());
int i2 = ConfigurationClassUtils.getOrder(bd2.getBeanDefinition());
return (i1 < i2) ? -1 : (i1 > i2) ? 1 : 0;
}
});
// Detect any custom bean name generation strategy supplied through the enclosing application context
SingletonBeanRegistry singletonRegistry = null;
if (registry instanceof SingletonBeanRegistry) {
singletonRegistry = (SingletonBeanRegistry) registry;
if (!this.localBeanNameGeneratorSet && singletonRegistry.containsSingleton(CONFIGURATION_BEAN_NAME_GENERATOR)) {
BeanNameGenerator generator = (BeanNameGenerator) singletonRegistry.getSingleton(CONFIGURATION_BEAN_NAME_GENERATOR);
this.componentScanBeanNameGenerator = generator;
this.importBeanNameGenerator = generator;
}
}
// Parse each @Configuration class
ConfigurationClassParser parser = new ConfigurationClassParser(
this.metadataReaderFactory, this.problemReporter, this.environment,
this.resourceLoader, this.componentScanBeanNameGenerator, registry);
Set candidates = new LinkedHashSet(configCandidates);
Set alreadyParsed = new HashSet(configCandidates.size());
do {
parser.parse(candidates);
parser.validate();
Set configClasses = new LinkedHashSet(parser.getConfigurationClasses());
configClasses.removeAll(alreadyParsed);
// Read the model and create bean definitions based on its content
if (this.reader == null) {
this.reader = new ConfigurationClassBeanDefinitionReader(
registry, this.sourceExtractor, this.resourceLoader, this.environment,
this.importBeanNameGenerator, parser.getImportRegistry());
}
this.reader.loadBeanDefinitions(configClasses);
alreadyParsed.addAll(configClasses);
candidates.clear();
if (registry.getBeanDefinitionCount() > candidateNames.length) {
String[] newCandidateNames = registry.getBeanDefinitionNames();
Set oldCandidateNames = new HashSet(Arrays.asList(candidateNames));
Set alreadyParsedClasses = new HashSet();
for (ConfigurationClass configurationClass : alreadyParsed) {
alreadyParsedClasses.add(configurationClass.getMetadata().getClassName());
}
for (String candidateName : newCandidateNames) {
if (!oldCandidateNames.contains(candidateName)) {
BeanDefinition beanDef = registry.getBeanDefinition(candidateName);
if (ConfigurationClassUtils.checkConfigurationClassCandidate(beanDef, this.metadataReaderFactory) &&
!alreadyParsedClasses.contains(beanDef.getBeanClassName())) {
candidates.add(new BeanDefinitionHolder(beanDef, candidateName));
}
}
}
candidateNames = newCandidateNames;
}
}
while (!candidates.isEmpty());
// Register the ImportRegistry as a bean in order to support ImportAware @Configuration classes
if (singletonRegistry != null) {
if (!singletonRegistry.containsSingleton(IMPORT_REGISTRY_BEAN_NAME)) {
singletonRegistry.registerSingleton(IMPORT_REGISTRY_BEAN_NAME, parser.getImportRegistry());
}
}
if (this.metadataReaderFactory instanceof CachingMetadataReaderFactory) {
((CachingMetadataReaderFactory) this.metadataReaderFactory).clearCache();
}
}
/**
* Post-processes a BeanFactory in search of Configuration class BeanDefinitions;
* any candidates are then enhanced by a {@link ConfigurationClassEnhancer}.
* Candidate status is determined by BeanDefinition attribute metadata.
* @see ConfigurationClassEnhancer
*/
public void enhanceConfigurationClasses(ConfigurableListableBeanFactory beanFactory) {
Map configBeanDefs = new LinkedHashMap();
for (String beanName : beanFactory.getBeanDefinitionNames()) {
BeanDefinition beanDef = beanFactory.getBeanDefinition(beanName);
if (ConfigurationClassUtils.isFullConfigurationClass(beanDef)) {
if (!(beanDef instanceof AbstractBeanDefinition)) {
throw new BeanDefinitionStoreException("Cannot enhance @Configuration bean definition '" +
beanName + "' since it is not stored in an AbstractBeanDefinition subclass");
}
else if (logger.isWarnEnabled() && beanFactory.containsSingleton(beanName)) {
logger.warn("Cannot enhance @Configuration bean definition '" + beanName +
"' since its singleton instance has been created too early. The typical cause " +
"is a non-static @Bean method with a BeanDefinitionRegistryPostProcessor " +
"return type: Consider declaring such methods as 'static'.");
}
configBeanDefs.put(beanName, (AbstractBeanDefinition) beanDef);
}
}
if (configBeanDefs.isEmpty()) {
// nothing to enhance -> return immediately
return;
}
ConfigurationClassEnhancer enhancer = new ConfigurationClassEnhancer();
for (Map.Entry entry : configBeanDefs.entrySet()) {
AbstractBeanDefinition beanDef = entry.getValue();
// If a @Configuration class gets proxied, always proxy the target class
beanDef.setAttribute(AutoProxyUtils.PRESERVE_TARGET_CLASS_ATTRIBUTE, Boolean.TRUE);
try {
// Set enhanced subclass of the user-specified bean class
Class configClass = beanDef.resolveBeanClass(this.beanClassLoader);
Class enhancedClass = enhancer.enhance(configClass, this.beanClassLoader);
if (configClass != enhancedClass) {
if (logger.isDebugEnabled()) {
logger.debug(String.format("Replacing bean definition '%s' existing class '%s' with " +
"enhanced class '%s'", entry.getKey(), configClass.getName(), enhancedClass.getName()));
}
beanDef.setBeanClass(enhancedClass);
}
}
catch (Throwable ex) {
throw new IllegalStateException("Cannot load configuration class: " + beanDef.getBeanClassName(), ex);
}
}
}
private static class ImportAwareBeanPostProcessor implements BeanPostProcessor, BeanFactoryAware, PriorityOrdered {
private BeanFactory beanFactory;
@Override
public void setBeanFactory(BeanFactory beanFactory) {
this.beanFactory = beanFactory;
}
@Override
public int getOrder() {
return Ordered.HIGHEST_PRECEDENCE;
}
@Override
public Object postProcessBeforeInitialization(Object bean, String beanName) {
if (bean instanceof ImportAware) {
ImportRegistry importRegistry = this.beanFactory.getBean(IMPORT_REGISTRY_BEAN_NAME, ImportRegistry.class);
AnnotationMetadata importingClass = importRegistry.getImportingClassFor(bean.getClass().getSuperclass().getName());
if (importingClass != null) {
((ImportAware) bean).setImportMetadata(importingClass);
}
}
return bean;
}
@Override
public Object postProcessAfterInitialization(Object bean, String beanName) {
return bean;
}
}
/**
* {@link InstantiationAwareBeanPostProcessorAdapter} that ensures
* {@link EnhancedConfiguration} beans are injected with the {@link BeanFactory}
* before the {@link AutowiredAnnotationBeanPostProcessor} runs (SPR-10668).
*/
private static class EnhancedConfigurationBeanPostProcessor extends InstantiationAwareBeanPostProcessorAdapter
implements PriorityOrdered, BeanFactoryAware {
private BeanFactory beanFactory;
@Override
public int getOrder() {
return Ordered.HIGHEST_PRECEDENCE;
}
@Override
public void setBeanFactory(BeanFactory beanFactory) {
this.beanFactory = beanFactory;
}
@Override
public PropertyValues postProcessPropertyValues(PropertyValues pvs, PropertyDescriptor[] pds, Object bean, String beanName) {
// Inject the BeanFactory before AutowiredAnnotationBeanPostProcessor's
// postProcessPropertyValues method attempts to auto-wire other configuration beans.
if (bean instanceof EnhancedConfiguration) {
((EnhancedConfiguration) bean).setBeanFactory(this.beanFactory);
}
return pvs;
}
}
}