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概述
该BeanPostProcessor为每个bean进行属性自动装配。这里支持的自动装配注解有：
@Autowired@Value@Inject(JSR-330) – 仅在@Inject类存在于classpath的情况才支持它
Springboot应用中，ApplicationContext创建时也会通过AnnotationConfigUtils#registerAnnotationConfigProcessors注册一个AutowiredAnnotationBeanPostProcessor到容器。非Springboot应用中，在XML配置中使用context:annotation-config/context:component-scan 这样的标签会启用一个缺省的AutowiredAnnotationBeanPostProcessor。
AnnotationConfigUtils位于包org.springframework.context.annotation。
AutowiredAnnotationBeanPostProcessor 对每个bean进行属性自动装配的任务，主要依赖它的两个方法实现:
MergedBeanDefinitionPostProcessor接口定义的方法postProcessMergedBeanDefinition用于发现和记录
bean的属性注入元数据:需要自动装配的成员属性/方法信息InstantiationAwareBeanPostProcessor接口定义的方法postProcessProperties用于根据上面所发现的属性注入元数据为
bean进行依赖"注入"
AutowiredAnnotationBeanPostProcessor 对每个bean进行属性自动装配(也就是执行依赖注入)的过程如下所示 :
源代码解析
package org.springframework.beans.factory.annotation;
import java.beans.PropertyDescriptor;
import java.lang.annotation.Annotation;
import java.lang.reflect.AccessibleObject;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.BeansException;
import org.springframework.beans.PropertyValues;
import org.springframework.beans.TypeConverter;
import org.springframework.beans.factory.BeanCreationException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.BeanFactoryUtils;
import org.springframework.beans.factory.InjectionPoint;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.UnsatisfiedDependencyException;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.config.DependencyDescriptor;
import org.springframework.beans.factory.config.InstantiationAwareBeanPostProcessorAdapter;
import org.springframework.beans.factory.support.LookupOverride;
import org.springframework.beans.factory.support.MergedBeanDefinitionPostProcessor;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.core.BridgeMethodResolver;
import org.springframework.core.MethodParameter;
import org.springframework.core.Ordered;
import org.springframework.core.PriorityOrdered;
import org.springframework.core.annotation.AnnotatedElementUtils;
import org.springframework.core.annotation.AnnotationAttributes;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.util.ReflectionUtils;
import org.springframework.util.StringUtils;
public class AutowiredAnnotationBeanPostProcessor extends InstantiationAwareBeanPostProcessorAdapter
implements MergedBeanDefinitionPostProcessor, PriorityOrdered, BeanFactoryAware {
protected final Log logger = LogFactory.getLog(getClass());
private final Set<Class<? extends Annotation>> autowiredAnnotationTypes = new LinkedHashSet<>(4);
private String requiredParameterName = "required";
private boolean requiredParameterValue = true;
private int order = Ordered.LOWEST_PRECEDENCE - 2;
@Nullable
private ConfigurableListableBeanFactory beanFactory;
private final Set<String> lookupMethodsChecked = Collections.newSetFromMap(new ConcurrentHashMap<>(256));
private final Map<Class<?>, Constructor<?>[]> candidateConstructorsCache = new ConcurrentHashMap<>(256);
private final Map<String, InjectionMetadata> injectionMetadataCache = new ConcurrentHashMap<>(256);
/**
* Create a new AutowiredAnnotationBeanPostProcessor
* for Spring's standardAutowired annotation.
* Also supports JSR-330's javax.inject.Inject annotation, if available.
*/
@SuppressWarnings("unchecked")
public AutowiredAnnotationBeanPostProcessor() {
// 缺省总是支持 @Autowired,@Value
this.autowiredAnnotationTypes.add(Autowired.class);
this.autowiredAnnotationTypes.add(Value.class);
// 对JSR-330 @Inject的支持仅限于该注解类存在于classpath的情况
try {
this.autowiredAnnotationTypes.add((Class<? extends Annotation>)
ClassUtils.forName("javax.inject.Inject", AutowiredAnnotationBeanPostProcessor.class.getClassLoader()));
logger.trace("JSR-330 'javax.inject.Inject' annotation found and supported for autowiring");
}
catch (ClassNotFoundException ex) {
// JSR-330 API not available - simply skip.
}
}
/**
* Set the 'autowired' annotation type, to be used on constructors, fields,
* setter methods and arbitrary config methods.
* The default autowired annotation type is the Spring-provided Autowired
* annotation, as well as Value.
* This setter property exists so that developers can provide their own
* (non-Spring-specific) annotation type to indicate that a member is supposed
* to be autowired.
* 设置所支持的自动配置注解，缺省情况下所支持的自动配置注解是@Autowired,@Value,@Inject,
* 但通过该方法，开发人员可以提供一个自定义的自动配置注解，而非Spring所提供的标准注解方式。
*/
public void setAutowiredAnnotationType(Class<? extends Annotation> autowiredAnnotationType) {
Assert.notNull(autowiredAnnotationType, "'autowiredAnnotationType' must not be null");
this.autowiredAnnotationTypes.clear();
this.autowiredAnnotationTypes.add(autowiredAnnotationType);
}
/**
* Set the 'autowired' annotation types, to be used on constructors, fields,
* setter methods and arbitrary config methods.
* The default autowired annotation type is the Spring-provided @Autowired
* annotation, as well as Value.
* This setter property exists so that developers can provide their own
* (non-Spring-specific) annotation types to indicate that a member is supposed
* to be autowired.
* 设置所支持的自动配置注解，缺省情况下所支持的自动配置注解是@Autowired,@Value,@Inject,
* 但通过该方法，开发人员可以提供多个自定义的自动配置注解，而非Spring所提供的标准注解方式。
*/
public void setAutowiredAnnotationTypes(Set<Class<? extends Annotation>> autowiredAnnotationTypes) {
Assert.notEmpty(autowiredAnnotationTypes, "'autowiredAnnotationTypes' must not be empty");
this.autowiredAnnotationTypes.clear();
this.autowiredAnnotationTypes.addAll(autowiredAnnotationTypes);
}
/**
* Set the name of a parameter of the annotation that specifies whether it is required.
* @see #setRequiredParameterValue(boolean)
*/
public void setRequiredParameterName(String requiredParameterName) {
this.requiredParameterName = requiredParameterName;
}
/**
* Set the boolean value that marks a dependency as required
* For example if using 'required=true' (the default), this value should be
* true; but if using 'optional=false', this value should be false.
* @see #setRequiredParameterName(String)
*/
public void setRequiredParameterValue(boolean requiredParameterValue) {
this.requiredParameterValue = requiredParameterValue;
}
public void setOrder(int order) {
this.order = order;
}
@Override
public int getOrder() {
return this.order;
}
@Override
public void setBeanFactory(BeanFactory beanFactory) {
if (!(beanFactory instanceof ConfigurableListableBeanFactory)) {
throw new IllegalArgumentException(
"AutowiredAnnotationBeanPostProcessor requires a ConfigurableListableBeanFactory: " + beanFactory);
}
this.beanFactory = (ConfigurableListableBeanFactory) beanFactory;
}
// 在每个bean实例化后，初始化前执行，获取并记录该bean属性注入的元数据，在随后的属性注入时使用
// 该方法由接口MergedBeanDefinitionPostProcessor定义
@Override
public void postProcessMergedBeanDefinition(RootBeanDefinition beanDefinition, Class<?> beanType, String beanName) {
// 获取指定bean的属性注入元数据
InjectionMetadata metadata = findAutowiringMetadata(beanName, beanType, null);
metadata.checkConfigMembers(beanDefinition);
}
@Override
public void resetBeanDefinition(String beanName) {
this.lookupMethodsChecked.remove(beanName);
this.injectionMetadataCache.remove(beanName);
}
@Override
@Nullable
public Constructor<?>[] determineCandidateConstructors(Class<?> beanClass, final String beanName)
throws BeanCreationException {
// Let's check for lookup methods here..
if (!this.lookupMethodsChecked.contains(beanName)) {
try {
ReflectionUtils.doWithMethods(beanClass, method -> {
Lookup lookup = method.getAnnotation(Lookup.class);
if (lookup != null) {
Assert.state(this.beanFactory != null, "No BeanFactory available");
LookupOverride override = new LookupOverride(method, lookup.value());
try {
RootBeanDefinition mbd = (RootBeanDefinition) this.beanFactory.getMergedBeanDefinition(beanName);
mbd.getMethodOverrides().addOverride(override);
}
catch (NoSuchBeanDefinitionException ex) {
throw new BeanCreationException(beanName,
"Cannot apply @Lookup to beans without corresponding bean definition");
}
}
});
}
catch (IllegalStateException ex) {
throw new BeanCreationException(beanName, "Lookup method resolution failed", ex);
}
this.lookupMethodsChecked.add(beanName);
}
// Quick check on the concurrent map first, with minimal locking.
Constructor<?>[] candidateConstructors = this.candidateConstructorsCache.get(beanClass);
if (candidateConstructors == null) {
// Fully synchronized resolution now...
synchronized (this.candidateConstructorsCache) {
candidateConstructors = this.candidateConstructorsCache.get(beanClass);
if (candidateConstructors == null) {
Constructor<?>[] rawCandidates;
try {
rawCandidates = beanClass.getDeclaredConstructors();
}
catch (Throwable ex) {
throw new BeanCreationException(beanName,
"Resolution of declared constructors on bean Class [" + beanClass.getName() +
"] from ClassLoader [" + beanClass.getClassLoader() + "] failed", ex);
}
List<Constructor<?>> candidates = new ArrayList<>(rawCandidates.length);
Constructor<?> requiredConstructor = null;
Constructor<?> defaultConstructor = null;
Constructor<?> primaryConstructor = BeanUtils.findPrimaryConstructor(beanClass);
int nonSyntheticConstructors = 0;
for (Constructor<?> candidate : rawCandidates) {
if (!candidate.isSynthetic()) {
nonSyntheticConstructors++;
}
else if (primaryConstructor != null) {
continue;
}
AnnotationAttributes ann = findAutowiredAnnotation(candidate);
if (ann == null) {
Class<?> userClass = ClassUtils.getUserClass(beanClass);
if (userClass != beanClass) {
try {
Constructor<?> superCtor =
userClass.getDeclaredConstructor(candidate.getParameterTypes());
ann = findAutowiredAnnotation(superCtor);
}
catch (NoSuchMethodException ex) {
// Simply proceed, no equivalent superclass constructor found...
}
}
}
if (ann != null) {
if (requiredConstructor != null) {
throw new BeanCreationException(beanName,
"Invalid autowire-marked constructor: " + candidate +
". Found constructor with 'required' Autowired annotation already: " +
requiredConstructor);
}
boolean required = determineRequiredStatus(ann);
if (required) {
if (!candidates.isEmpty()) {
throw new BeanCreationException(beanName,
"Invalid autowire-marked constructors: " + candidates +
". Found constructor with 'required' Autowired annotation: " +
candidate);
}
requiredConstructor = candidate;
}
candidates.add(candidate);
}
else if (candidate.getParameterCount() == 0) {
defaultConstructor = candidate;
}
}
if (!candidates.isEmpty()) {
// Add default constructor to list of optional constructors, as fallback.
if (requiredConstructor == null) {
if (defaultConstructor != null) {
candidates.add(defaultConstructor);
}
else if (candidates.size() == 1 && logger.isInfoEnabled()) {
logger.info("Inconsistent constructor declaration on bean with name '" + beanName +
"': single autowire-marked constructor flagged as optional - " +
"this constructor is effectively required since there is no " +
"default constructor to fall back to: " + candidates.get(0));
}
}
candidateConstructors = candidates.toArray(new Constructor<?>[0]);
}
else if (rawCandidates.length == 1 && rawCandidates[0].getParameterCount() > 0) {
candidateConstructors = new Constructor<?>[] {rawCandidates[0]};
}
else if (nonSyntheticConstructors == 2 && primaryConstructor != null &&
defaultConstructor != null && !primaryConstructor.equals(defaultConstructor)) {
candidateConstructors = new Constructor<?>[] {primaryConstructor, defaultConstructor};
}
else if (nonSyntheticConstructors == 1 && primaryConstructor != null) {
candidateConstructors = new Constructor<?>[] {primaryConstructor};
}
else {
candidateConstructors = new Constructor<?>[0];
}
this.candidateConstructorsCache.put(beanClass, candidateConstructors);
}
}
}
return (candidateConstructors.length > 0 ? candidateConstructors : null);
}
// 接口 InstantiationAwareBeanPostProcessor 定义的方法，用于在bean创建时填充属性阶段
// 对bean进行相应的属性注入
// 在同一个bean的创建过程中 :
// 1. postProcessProperties 的调用发生在 postProcessMergedBeanDefinition 之后
// 2. postProcessMergedBeanDefinition 用于发现和缓存该bean有哪些自动装配成员
// 3. postProcessProperties 用于对所发现的自动装配成员进行自动转配，也就是执行依赖注入的"注入"
@Override
public PropertyValues postProcessProperties(PropertyValues pvs, Object bean, String beanName) {
// 找到该bean需要自动装配的成员，已经由postProcessMergedBeanDefinition放在缓存中
InjectionMetadata metadata = findAutowiringMetadata(beanName, bean.getClass(), pvs);
try {
// 进行自动装配成员的自动装配，也就是真正的依赖"注入"
metadata.inject(bean, beanName, pvs);
}
catch (BeanCreationException ex) {
throw ex;
}
catch (Throwable ex) {
throw new BeanCreationException(beanName, "Injection of autowired dependencies failed", ex);
}
return pvs;
}
@Deprecated
@Override
public PropertyValues postProcessPropertyValues(
PropertyValues pvs, PropertyDescriptor[] pds, Object bean, String beanName) {
return postProcessProperties(pvs, bean, beanName);
}
/**
* 'Native' processing method for direct calls with an arbitrary target instance,
* resolving all of its fields and methods which are annotated with @Autowired.
* @param bean the target instance to process
* @throws BeanCreationException if autowiring failed
*/
public void processInjection(Object bean) throws BeanCreationException {
Class<?> clazz = bean.getClass();
InjectionMetadata metadata = findAutowiringMetadata(clazz.getName(), clazz, null);
try {
metadata.inject(bean, null, null);
}
catch (BeanCreationException ex) {
throw ex;
}
catch (Throwable ex) {
throw new BeanCreationException(
"Injection of autowired dependencies failed for class [" + clazz + "]", ex);
}
}
// 获取指定bean的注入元数据，使用了缓存机制，首先从缓存中尝试获取，如果缓存中没找到，从bean类上
// 直接获取并缓存
private InjectionMetadata findAutowiringMetadata(String beanName, Class<?> clazz, @Nullable PropertyValues pvs) {
// Fall back to class name as cache key, for backwards compatibility with custom callers.
String cacheKey = (StringUtils.hasLength(beanName) ? beanName : clazz.getName());
// Quick check on the concurrent map first, with minimal locking.
InjectionMetadata metadata = this.injectionMetadataCache.get(cacheKey);
if (InjectionMetadata.needsRefresh(metadata, clazz)) {
synchronized (this.injectionMetadataCache) {
metadata = this.injectionMetadataCache.get(cacheKey);
if (InjectionMetadata.needsRefresh(metadata, clazz)) {
if (metadata != null) {
metadata.clear(pvs);
}
// 直接从bean类上获取注入元数据并缓存
metadata = buildAutowiringMetadata(clazz);
this.injectionMetadataCache.put(cacheKey, metadata);
}
}
}
return metadata;
}
// 从bean的类clazz开始沿着继承链遍历直到遇到null或者基类Object结束，遍历遇到的每个类声明
// 的实例成员属性/成员方法(注意:静态成员属性方法会被排除)查看其是否需要自动装配，如果该
// 实例成员属性/成员方法需要自动装配，将它们包装成AutowiredFieldElement/AutowiredMethodElement
// 然后放在同一个InjectionMetadata对象中返回。
private InjectionMetadata buildAutowiringMetadata(final Class<?> clazz) {
List<InjectionMetadata.InjectedElement> elements = new ArrayList<>();
Class<?> targetClass = clazz;
do {
final List<InjectionMetadata.InjectedElement> currElements = new ArrayList<>();
ReflectionUtils.doWithLocalFields(targetClass, field -> {
AnnotationAttributes ann = findAutowiredAnnotation(field);
if (ann != null) {
if (Modifier.isStatic(field.getModifiers())) {
if (logger.isInfoEnabled()) {
logger.info("Autowired annotation is not supported on static fields: " + field);
}
return;
}
boolean required = determineRequiredStatus(ann);
currElements.add(new AutowiredFieldElement(field, required));
}
});
ReflectionUtils.doWithLocalMethods(targetClass, method -> {
Method bridgedMethod = BridgeMethodResolver.findBridgedMethod(method);
if (!BridgeMethodResolver.isVisibilityBridgeMethodPair(method, bridgedMethod)) {
return;
}
AnnotationAttributes ann = findAutowiredAnnotation(bridgedMethod);
if (ann != null && method.equals(ClassUtils.getMostSpecificMethod(method, clazz))) {
if (Modifier.isStatic(method.getModifiers())) {
if (logger.isInfoEnabled()) {
logger.info("Autowired annotation is not supported on static methods: " + method);
}
return;
}
if (method.getParameterCount() == 0) {
if (logger.isInfoEnabled()) {
logger.info("Autowired annotation should only be used on methods with parameters: " +
method);
}
}
boolean required = determineRequiredStatus(ann);
PropertyDescriptor pd = BeanUtils.findPropertyForMethod(bridgedMethod, clazz);
currElements.add(new AutowiredMethodElement(method, required, pd));
}
});
elements.addAll(0, currElements);
targetClass = targetClass.getSuperclass();
}
while (targetClass != null && targetClass != Object.class);
return new InjectionMetadata(clazz, elements);
}
@Nullable
private AnnotationAttributes findAutowiredAnnotation(AccessibleObject ao) {
if (ao.getAnnotations().length > 0) { // autowiring annotations have to be local
for (Class<? extends Annotation> type : this.autowiredAnnotationTypes) {
AnnotationAttributes attributes = AnnotatedElementUtils.getMergedAnnotationAttributes(ao, type);
if (attributes != null) {
return attributes;
}
}
}
return null;
}
/**
* Determine if the annotated field or method requires its dependency.
* A 'required' dependency means that autowiring should fail when no beans
* are found. Otherwise, the autowiring process will simply bypass the field
* or method when no beans are found.
* @param ann the Autowired annotation
* @return whether the annotation indicates that a dependency is required
*/
protected boolean determineRequiredStatus(AnnotationAttributes ann) {
return (!ann.containsKey(this.requiredParameterName) ||
this.requiredParameterValue == ann.getBoolean(this.requiredParameterName));
}
/**
* Obtain all beans of the given type as autowire candidates.
* @param type the type of the bean
* @return the target beans, or an empty Collection if no bean of this type is found
* @throws BeansException if bean retrieval failed
*/
protected <T> Map<String, T> findAutowireCandidates(Class<T> type) throws BeansException {
if (this.beanFactory == null) {
throw new IllegalStateException("No BeanFactory configured - " +
"override the getBeanOfType method or specify the 'beanFactory' property");
}
return BeanFactoryUtils.beansOfTypeIncludingAncestors(this.beanFactory, type);
}
/**
* Register the specified bean as dependent on the autowired beans.
*/
private void registerDependentBeans(@Nullable String beanName, Set<String> autowiredBeanNames) {
if (beanName != null) {
for (String autowiredBeanName : autowiredBeanNames) {
if (this.beanFactory != null && this.beanFactory.containsBean(autowiredBeanName)) {
this.beanFactory.registerDependentBean(autowiredBeanName, beanName);
}
if (logger.isTraceEnabled()) {
logger.trace("Autowiring by type from bean name '" + beanName +
"' to bean named '" + autowiredBeanName + "'");
}
}
}
}
/**
* Resolve the specified cached method argument or field value.
*/
@Nullable
private Object resolvedCachedArgument(@Nullable String beanName, @Nullable Object cachedArgument) {
if (cachedArgument instanceof DependencyDescriptor) {
DependencyDescriptor descriptor = (DependencyDescriptor) cachedArgument;
Assert.state(this.beanFactory != null, "No BeanFactory available");
return this.beanFactory.resolveDependency(descriptor, beanName, null, null);
}
else {
return cachedArgument;
}
}
/**
* Class representing injection information about an annotated field.
*/
private class AutowiredFieldElement extends InjectionMetadata.InjectedElement {
private final boolean required;
private volatile boolean cached = false;
@Nullable
private volatile Object cachedFieldValue;
public AutowiredFieldElement(Field field, boolean required) {
super(field, null);
this.required = required;
}
@Override
protected void inject(Object bean, @Nullable String beanName, @Nullable PropertyValues pvs) throws Throwable {
Field field = (Field) this.member;
Object value;
if (this.cached) {
value = resolvedCachedArgument(beanName, this.cachedFieldValue);
}
else {
DependencyDescriptor desc = new DependencyDescriptor(field, this.required);
desc.setContainingClass(bean.getClass());
Set<String> autowiredBeanNames = new LinkedHashSet<>(1);
Assert.state(beanFactory != null, "No BeanFactory available");
TypeConverter typeConverter = beanFactory.getTypeConverter();
try {
value = beanFactory.resolveDependency(desc, beanName, autowiredBeanNames, typeConverter);
}
catch (BeansException ex) {
throw new UnsatisfiedDependencyException(null, beanName, new InjectionPoint(field), ex);
}
synchronized (this) {
if (!this.cached) {
if (value != null || this.required) {
this.cachedFieldValue = desc;
registerDependentBeans(beanName, autowiredBeanNames);
if (autowiredBeanNames.size() == 1) {
String autowiredBeanName = autowiredBeanNames.iterator().next();
if (beanFactory.containsBean(autowiredBeanName) &&
beanFactory.isTypeMatch(autowiredBeanName, field.getType())) {
this.cachedFieldValue = new ShortcutDependencyDescriptor(
desc, autowiredBeanName, field.getType());
}
}
}
else {
this.cachedFieldValue = null;
}
this.cached = true;
}
}
}
if (value != null) {
ReflectionUtils.makeAccessible(field);
field.set(bean, value);
}
}
}
/**
* Class representing injection information about an annotated method.
*/
private class AutowiredMethodElement extends InjectionMetadata.InjectedElement {
private final boolean required;
private volatile boolean cached = false;
@Nullable
private volatile Object[] cachedMethodArguments;
public AutowiredMethodElement(Method method, boolean required, @Nullable PropertyDescriptor pd) {
super(method, pd);
this.required = required;
}
@Override
protected void inject(Object bean, @Nullable String beanName, @Nullable PropertyValues pvs) throws Throwable {
if (checkPropertySkipping(pvs)) {
return;
}
Method method = (Method) this.member;
Object[] arguments;
if (this.cached) {
// Shortcut for avoiding synchronization...
arguments = resolveCachedArguments(beanName);
}
else {
Class<?>[] paramTypes = method.getParameterTypes();
arguments = new Object[paramTypes.length];
DependencyDescriptor[] descriptors = new DependencyDescriptor[paramTypes.length];
Set<String> autowiredBeans = new LinkedHashSet<>(paramTypes.length);
Assert.state(beanFactory != null, "No BeanFactory available");
TypeConverter typeConverter = beanFactory.getTypeConverter();
for (int i = 0; i < arguments.length; i++) {
MethodParameter methodParam = new MethodParameter(method, i);
DependencyDescriptor currDesc = new DependencyDescriptor(methodParam, this.required);
currDesc.setContainingClass(bean.getClass());
descriptors[i] = currDesc;
try {
Object arg = beanFactory.resolveDependency(currDesc, beanName, autowiredBeans, typeConverter);
if (arg == null && !this.required) {
arguments = null;
break;
}
arguments[i] = arg;
}
catch (BeansException ex) {
throw new UnsatisfiedDependencyException(null, beanName, new InjectionPoint(methodParam), ex);
}
}
synchronized (this) {
if (!this.cached) {
if (arguments != null) {
Object[] cachedMethodArguments = new Object[paramTypes.length];
System.arraycopy(descriptors, 0, cachedMethodArguments, 0, arguments.length);
registerDependentBeans(beanName, autowiredBeans);
if (autowiredBeans.size() == paramTypes.length) {
Iterator<String> it = autowiredBeans.iterator();
for (int i = 0; i < paramTypes.length; i++) {
String autowiredBeanName = it.next();
if (beanFactory.containsBean(autowiredBeanName) &&
beanFactory.isTypeMatch(autowiredBeanName, paramTypes[i])) {
cachedMethodArguments[i] = new ShortcutDependencyDescriptor(
descriptors[i], autowiredBeanName, paramTypes[i]);
}
}
}
this.cachedMethodArguments = cachedMethodArguments;
}
else {
this.cachedMethodArguments = null;
}
this.cached = true;
}
}
}
if (arguments != null) {
try {
ReflectionUtils.makeAccessible(method);
method.invoke(bean, arguments);
}
catch (InvocationTargetException ex) {
throw ex.getTargetException();
}
}
}
@Nullable
private Object[] resolveCachedArguments(@Nullable String beanName) {
Object[] cachedMethodArguments = this.cachedMethodArguments;
if (cachedMethodArguments == null) {
return null;
}
Object[] arguments = new Object[cachedMethodArguments.length];
for (int i = 0; i < arguments.length; i++) {
arguments[i] = resolvedCachedArgument(beanName, cachedMethodArguments[i]);
}
return arguments;
}
}
/**
* DependencyDescriptor variant with a pre-resolved target bean name.
*/
@SuppressWarnings("serial")
private static class ShortcutDependencyDescriptor extends DependencyDescriptor {
private final String shortcut;
private final Class<?> requiredType;
public ShortcutDependencyDescriptor(DependencyDescriptor original, String shortcut, Class<?> requiredType) {
super(original);
this.shortcut = shortcut;
this.requiredType = requiredType;
}
@Override
public Object resolveShortcut(BeanFactory beanFactory) {
return beanFactory.getBean(this.shortcut, this.requiredType);
}
}
}