/*
* Copyright 2002-2011 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.io.IOException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
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.beans.factory.annotation.AnnotatedBeanDefinition;
import org.springframework.beans.factory.annotation.Autowire;
import org.springframework.beans.factory.annotation.RequiredAnnotationBeanPostProcessor;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.BeanDefinitionHolder;
import org.springframework.beans.factory.parsing.Location;
import org.springframework.beans.factory.parsing.Problem;
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.AbstractBeanDefinitionReader;
import org.springframework.beans.factory.support.BeanDefinitionReader;
import org.springframework.beans.factory.support.BeanDefinitionReaderUtils;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.GenericBeanDefinition;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.core.io.Resource;
import org.springframework.core.io.ResourceLoader;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.core.type.MethodMetadata;
import org.springframework.core.type.classreading.MetadataReader;
import org.springframework.core.type.classreading.MetadataReaderFactory;
import org.springframework.util.StringUtils;
/**
* Reads a given fully-populated set of ConfigurationClass instances, registering bean
* definitions with the given {@link BeanDefinitionRegistry} based on its contents.
*
* <p>This class was modeled after the {@link BeanDefinitionReader} hierarchy, but does
* not implement/extend any of its artifacts as a set of configuration classes is not a
* {@link Resource}.
*
* @author Chris Beams
* @author Juergen Hoeller
* @since 3.0
* @see ConfigurationClassParser
*/
class ConfigurationClassBeanDefinitionReader {
private static final Log logger = LogFactory.getLog(ConfigurationClassBeanDefinitionReader.class);
private final BeanDefinitionRegistry registry;
private final SourceExtractor sourceExtractor;
private final ProblemReporter problemReporter;
private final MetadataReaderFactory metadataReaderFactory;
private ResourceLoader resourceLoader;
/**
* Create a new {@link ConfigurationClassBeanDefinitionReader} instance that will be used
* to populate the given {@link BeanDefinitionRegistry}.
* @param problemReporter
* @param metadataReaderFactory
*/
public ConfigurationClassBeanDefinitionReader(BeanDefinitionRegistry registry, SourceExtractor sourceExtractor,
ProblemReporter problemReporter, MetadataReaderFactory metadataReaderFactory,
ResourceLoader resourceLoader) {
this.registry = registry;
this.sourceExtractor = sourceExtractor;
this.problemReporter = problemReporter;
this.metadataReaderFactory = metadataReaderFactory;
this.resourceLoader = resourceLoader;
}
/**
* Read {@code configurationModel}, registering bean definitions with {@link #registry}
* based on its contents.
*/
public void loadBeanDefinitions(Set<ConfigurationClass> configurationModel) {
for (ConfigurationClass configClass : configurationModel) {
loadBeanDefinitionsForConfigurationClass(configClass);
}
}
/**
* Read a particular {@link ConfigurationClass}, registering bean definitions for the
* class itself, all its {@link Bean} methods
*/
private void loadBeanDefinitionsForConfigurationClass(ConfigurationClass configClass) {
doLoadBeanDefinitionForConfigurationClassIfNecessary(configClass);
for (BeanMethod beanMethod : configClass.getBeanMethods()) {
loadBeanDefinitionsForBeanMethod(beanMethod);
}
loadBeanDefinitionsFromImportedResources(configClass.getImportedResources());
}
/**
* Register the {@link Configuration} class itself as a bean definition.
*/
private void doLoadBeanDefinitionForConfigurationClassIfNecessary(ConfigurationClass configClass) {
if (configClass.getBeanName() != null) {
// a bean definition already exists for this configuration class -> nothing to do
return;
}
// no bean definition exists yet -> this must be an imported configuration class (@Import).
BeanDefinition configBeanDef = new GenericBeanDefinition();
String className = configClass.getMetadata().getClassName();
configBeanDef.setBeanClassName(className);
if (ConfigurationClassUtils.checkConfigurationClassCandidate(configBeanDef, this.metadataReaderFactory)) {
String configBeanName = BeanDefinitionReaderUtils.registerWithGeneratedName((AbstractBeanDefinition)configBeanDef, this.registry);
configClass.setBeanName(configBeanName);
if (logger.isDebugEnabled()) {
logger.debug(String.format("Registered bean definition for imported @Configuration class %s", configBeanName));
}
}
else {
try {
MetadataReader reader = this.metadataReaderFactory.getMetadataReader(className);
AnnotationMetadata metadata = reader.getAnnotationMetadata();
this.problemReporter.error(
new InvalidConfigurationImportProblem(className, reader.getResource(), metadata));
}
catch (IOException ex) {
throw new IllegalStateException("Could not create MetadataReader for class " + className);
}
}
}
/**
* Read the given {@link BeanMethod}, registering bean definitions
* with the BeanDefinitionRegistry based on its contents.
*/
private void loadBeanDefinitionsForBeanMethod(BeanMethod beanMethod) {
ConfigurationClass configClass = beanMethod.getConfigurationClass();
MethodMetadata metadata = beanMethod.getMetadata();
RootBeanDefinition beanDef = new ConfigurationClassBeanDefinition(configClass);
beanDef.setResource(configClass.getResource());
beanDef.setSource(this.sourceExtractor.extractSource(metadata, configClass.getResource()));
if (metadata.isStatic()) {
// static @Bean method
beanDef.setBeanClassName(configClass.getMetadata().getClassName());
beanDef.setFactoryMethodName(metadata.getMethodName());
}
else {
// instance @Bean method
beanDef.setFactoryBeanName(configClass.getBeanName());
beanDef.setUniqueFactoryMethodName(metadata.getMethodName());
}
beanDef.setAutowireMode(RootBeanDefinition.AUTOWIRE_CONSTRUCTOR);
beanDef.setAttribute(RequiredAnnotationBeanPostProcessor.SKIP_REQUIRED_CHECK_ATTRIBUTE, Boolean.TRUE);
// consider role
Map<String, Object> roleAttributes = metadata.getAnnotationAttributes(Role.class.getName());
if (roleAttributes != null) {
int role = (Integer) roleAttributes.get("value");
beanDef.setRole(role);
}
// consider name and any aliases
Map<String, Object> beanAttributes = metadata.getAnnotationAttributes(Bean.class.getName());
List<String> names = new ArrayList<String>(Arrays.asList((String[]) beanAttributes.get("name")));
String beanName = (names.size() > 0 ? names.remove(0) : beanMethod.getMetadata().getMethodName());
for (String alias : names) {
this.registry.registerAlias(beanName, alias);
}
// has this already been overridden (e.g. via XML)?
if (this.registry.containsBeanDefinition(beanName)) {
BeanDefinition existingBeanDef = registry.getBeanDefinition(beanName);
// is the existing bean definition one that was created from a configuration class?
if (!(existingBeanDef instanceof ConfigurationClassBeanDefinition)) {
// no -> then it's an external override, probably XML
// overriding is legal, return immediately
if (logger.isDebugEnabled()) {
logger.debug(String.format("Skipping loading bean definition for %s: a definition for bean " +
"'%s' already exists. This is likely due to an override in XML.", beanMethod, beanName));
}
return;
}
}
if (metadata.isAnnotated(Primary.class.getName())) {
beanDef.setPrimary(true);
}
// is this bean to be instantiated lazily?
if (metadata.isAnnotated(Lazy.class.getName())) {
beanDef.setLazyInit((Boolean) metadata.getAnnotationAttributes(Lazy.class.getName()).get("value"));
}
else if (configClass.getMetadata().isAnnotated(Lazy.class.getName())){
beanDef.setLazyInit((Boolean) configClass.getMetadata().getAnnotationAttributes(Lazy.class.getName()).get("value"));
}
if (metadata.isAnnotated(DependsOn.class.getName())) {
String[] dependsOn = (String[]) metadata.getAnnotationAttributes(DependsOn.class.getName()).get("value");
if (dependsOn.length > 0) {
beanDef.setDependsOn(dependsOn);
}
}
Autowire autowire = (Autowire) beanAttributes.get("autowire");
if (autowire.isAutowire()) {
beanDef.setAutowireMode(autowire.value());
}
String initMethodName = (String) beanAttributes.get("initMethod");
if (StringUtils.hasText(initMethodName)) {
beanDef.setInitMethodName(initMethodName);
}
String destroyMethodName = (String) beanAttributes.get("destroyMethod");
if (StringUtils.hasText(destroyMethodName)) {
beanDef.setDestroyMethodName(destroyMethodName);
}
// consider scoping
ScopedProxyMode proxyMode = ScopedProxyMode.NO;
Map<String, Object> scopeAttributes = metadata.getAnnotationAttributes(Scope.class.getName());
if (scopeAttributes != null) {
beanDef.setScope((String) scopeAttributes.get("value"));
proxyMode = (ScopedProxyMode) scopeAttributes.get("proxyMode");
if (proxyMode == ScopedProxyMode.DEFAULT) {
proxyMode = ScopedProxyMode.NO;
}
}
// replace the original bean definition with the target one, if necessary
BeanDefinition beanDefToRegister = beanDef;
if (proxyMode != ScopedProxyMode.NO) {
BeanDefinitionHolder proxyDef = ScopedProxyCreator.createScopedProxy(
new BeanDefinitionHolder(beanDef, beanName), this.registry, proxyMode == ScopedProxyMode.TARGET_CLASS);
beanDefToRegister = proxyDef.getBeanDefinition();
}
if (logger.isDebugEnabled()) {
logger.debug(String.format("Registering bean definition for @Bean method %s.%s()", configClass.getMetadata().getClassName(), beanName));
}
registry.registerBeanDefinition(beanName, beanDefToRegister);
}
private void loadBeanDefinitionsFromImportedResources(Map<String, Class<?>> importedResources) {
Map<Class<?>, BeanDefinitionReader> readerInstanceCache = new HashMap<Class<?>, BeanDefinitionReader>();
for (Map.Entry<String, Class<?>> entry : importedResources.entrySet()) {
String resource = entry.getKey();
Class<?> readerClass = entry.getValue();
if (!readerInstanceCache.containsKey(readerClass)) {
try {
// Instantiate the specified BeanDefinitionReader
BeanDefinitionReader readerInstance = (BeanDefinitionReader)
readerClass.getConstructor(BeanDefinitionRegistry.class).newInstance(this.registry);
// Delegate the current ResourceLoader to it if possible
if (readerInstance instanceof AbstractBeanDefinitionReader) {
((AbstractBeanDefinitionReader)readerInstance).setResourceLoader(this.resourceLoader);
}
readerInstanceCache.put(readerClass, readerInstance);
}
catch (Exception ex) {
throw new IllegalStateException("Could not instantiate BeanDefinitionReader class [" + readerClass.getName() + "]");
}
}
BeanDefinitionReader reader = readerInstanceCache.get(readerClass);
// TODO SPR-6310: qualify relative path locations as done in AbstractContextLoader.modifyLocations
reader.loadBeanDefinitions(resource);
}
}
/**
* {@link RootBeanDefinition} marker subclass used to signify that a bean definition
* was created from a configuration class as opposed to any other configuration source.
* Used in bean overriding cases where it's necessary to determine whether the bean
* definition was created externally.
*/
@SuppressWarnings("serial")
private static class ConfigurationClassBeanDefinition extends RootBeanDefinition implements AnnotatedBeanDefinition {
private AnnotationMetadata annotationMetadata;
public ConfigurationClassBeanDefinition(ConfigurationClass configClass) {
this.annotationMetadata = configClass.getMetadata();
}
private ConfigurationClassBeanDefinition(ConfigurationClassBeanDefinition original) {
super(original);
this.annotationMetadata = original.annotationMetadata;
}
public AnnotationMetadata getMetadata() {
return this.annotationMetadata;
}
@Override
public boolean isFactoryMethod(Method candidate) {
return (super.isFactoryMethod(candidate) && BeanAnnotationHelper.isBeanAnnotated(candidate));
}
@Override
public ConfigurationClassBeanDefinition cloneBeanDefinition() {
return new ConfigurationClassBeanDefinition(this);
}
}
/**
* Configuration classes must be annotated with {@link Configuration @Configuration} or
* declare at least one {@link Bean @Bean} method.
*/
private static class InvalidConfigurationImportProblem extends Problem {
public InvalidConfigurationImportProblem(String className, Resource resource, AnnotationMetadata metadata) {
super(String.format("%s was @Import'ed but is not annotated with @Configuration " +
"nor does it declare any @Bean methods; it does not implement ImportSelector " +
"or extend ImportBeanDefinitionRegistrar. Update the class to meet one of these requirements " +
"or do not attempt to @Import it.", className), new Location(resource, metadata));
}
}
}