spring单例bean注册表类图
package org.springframework.core;
/**
* 定义单例别名的注册,查询服务
* @author Juergen Hoeller
* @since 2.5.2
*/
public interface AliasRegistry {
/**
* 给指定的bean设置别名
* @param bean名称
* @param alias注册的别名
* @throws IllegalStateException if the alias is already in use
* and may not be overridden
*/
void registerAlias(String name, String alias);
/**
* 从注册表中移除指定的别名
* @param alias the alias to remove
* @throws IllegalStateException if no such alias was found
*/
void removeAlias(String alias);
/**
* 判断给点的名称是否是别名
* (as opposed to the name of an actually registered component).
* @param name the name to check
* @return whether the given name is an alias
*/
boolean isAlias(String name);
/**
* 返回指定bean名称的多有别名
* @param name the name to check for aliases
* @return the aliases, or an empty array if none
*/
String[] getAliases(String name);
}
package org.springframework.core;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
import org.springframework.util.StringValueResolver;
/**
* 提供单例别名的注册,查询服务
* @author Juergen Hoeller
* @since 2.5.2
*/
public class SimpleAliasRegistry implements AliasRegistry {
/** 别名缓存（线程安全的 ）别名为key，name是value */
private final Map aliasMap = new ConcurrentHashMap(16);
@Override
public void registerAlias(String name, String alias) {
//注册别名时：name和别名不能为空
Assert.hasText(name, "'name' must not be empty");
Assert.hasText(alias, "'alias' must not be empty");
//如果name已经注册，就移除
if (alias.equals(name)) {
this.aliasMap.remove(alias);
} else {
//通过别名获取对应的name
String registeredName = this.aliasMap.get(alias);
if (registeredName != null) {
//name也相同，直接返回
if (registeredName.equals(name)) {
return;
}
//如果不允许覆盖，直接抛异常
if (!allowAliasOverriding()) {
throw new IllegalStateException("Cannot register alias '" + alias + "' for name '" +
name + "': It is already registered for name '" + registeredName + "'.");
}
}
//检查name：a alias：b 和name：b alias：a 是否存在
checkForAliasCircle(name, alias);
//都不存在，缓存别名
this.aliasMap.put(alias, name);
}
}
/**
* 是否允许覆盖 默认允许
* Default is {@code true}.
*/
protected boolean allowAliasOverriding() {
return true;
}
/**
* 确认给定的bean和别名是否注册，排除循环注册的情况
* @param name the name to check
* @param alias the alias to look for
* @since 4.2.1
*/
public boolean hasAlias(String name, String alias) {
for (Map.Entry entry : this.aliasMap.entrySet()) {
String registeredName = entry.getValue();
if (registeredName.equals(name)) {
String registeredAlias = entry.getKey();
return (registeredAlias.equals(alias) || hasAlias(registeredAlias, alias));
}
}
return false;
}
@Override
public void removeAlias(String alias) {
String name = this.aliasMap.remove(alias);
if (name == null) {
throw new IllegalStateException("No alias '" + alias + "' registered");
}
}
@Override
public boolean isAlias(String name) {
return this.aliasMap.containsKey(name);
}
@Override
public String[] getAliases(String name) {
List result = new ArrayList();
synchronized (this.aliasMap) {
retrieveAliases(name, result);
}
return StringUtils.toStringArray(result);
}
/**
* 检索给定name的所有别名，结果放在result中.
* @param name the target name to find aliases for
* @param result the resulting aliases list
*/
private void retrieveAliases(String name, List result) {
for (Map.Entry entry : this.aliasMap.entrySet()) {
String registeredName = entry.getValue();
if (registeredName.equals(name)) {
String alias = entry.getKey();
result.add(alias);
retrieveAliases(alias, result);
}
}
}
/**
* 通过StringValueResolver解析别名，并重新注册（例如：别名中包含占位符）
* @param valueResolver the StringValueResolver to apply
*/
public void resolveAliases(StringValueResolver valueResolver) {
Assert.notNull(valueResolver, "StringValueResolver must not be null");
synchronized (this.aliasMap) {
//copy一份缓存
Map aliasCopy = new HashMap(this.aliasMap);
for (String alias : aliasCopy.keySet()) {
String registeredName = aliasCopy.get(alias);
//获取解析之后的别名
String resolvedAlias = valueResolver.resolveStringValue(alias);
//解析之后的name
String resolvedName = valueResolver.resolveStringValue(registeredName);
//如果别名和name已经注册，就移除，解决循环依赖的问题
if (resolvedAlias == null || resolvedName == null || resolvedAlias.equals(resolvedName)) {
this.aliasMap.remove(alias);
}else if (!resolvedAlias.equals(alias)) {//解析别名和原别名不同
String existingName = this.aliasMap.get(resolvedAlias);
if (existingName != null) {//解析之后的别名和name存在，移除
if (existingName.equals(resolvedName)) {
this.aliasMap.remove(alias);
break;
}
//别名相同，name不同抛异常，注册失败
throw new IllegalStateException(
"Cannot register resolved alias '" + resolvedAlias + "' (original: '" + alias +
"') for name '" + resolvedName + "': It is already registered for name '" +
registeredName + "'.");
}
checkForAliasCircle(resolvedName, resolvedAlias);
//删除原来的别名，重新注册
this.aliasMap.remove(alias);
this.aliasMap.put(resolvedAlias, resolvedName);
}
else if (!registeredName.equals(resolvedName)) {//如果名称不相同，直接注册
this.aliasMap.put(alias, resolvedName);
}
}
}
}
/**
* 检查别名和name是否循环注册
* @param name the candidate name
* @param alias the candidate alias
* @see #registerAlias
* @see #hasAlias
*/
protected void checkForAliasCircle(String name, String alias) {
if (hasAlias(alias, name)) {
throw new IllegalStateException("Cannot register alias '" + alias +
"' for name '" + name + "': Circular reference - '" +
name + "' is a direct or indirect alias for '" + alias + "' already");
}
}
/**
* 获取以name为key的name
* @param name the user-specified name
* @return the transformed name
*/
public String canonicalName(String name) {
String canonicalName = name;
// Handle aliasing...
String resolvedName;
do {
resolvedName = this.aliasMap.get(canonicalName);
if (resolvedName != null) {
canonicalName = resolvedName;
}
}
while (resolvedName != null);
return canonicalName;
}
}
package org.springframework.beans.factory.config; /** * 定义bean的注册、查询服务 * *The {@link ConfigurableBeanFactory} interface extends this interface. * * @author Juergen Hoeller * @since 2.0 * @see ConfigurableBeanFactory * @see org.springframework.beans.factory.support.DefaultSingletonBeanRegistry * @see org.springframework.beans.factory.support.AbstractBeanFactory */ public interface SingletonBeanRegistry { /** * 注册单例bean * @param beanName the name of the bean * @param singletonObject the existing singleton object * @see org.springframework.beans.factory.InitializingBean#afterPropertiesSet * @see org.springframework.beans.factory.DisposableBean#destroy * @see org.springframework.beans.factory.support.BeanDefinitionRegistry#registerBeanDefinition */ void registerSingleton(String beanName, Object singletonObject); /** * 通过name获取一个单例bean对象 * @param beanName the name of the bean to look for * @return the registered singleton object, or {@code null} if none found * @see ConfigurableListableBeanFactory#getBeanDefinition */ Object getSingleton(String beanName); /** * 检查注册表中是否包含该单例bean * @param beanName the name of the bean to look for * @return if this bean factory contains a singleton instance with the given name * @see #registerSingleton * @see org.springframework.beans.factory.ListableBeanFactory#containsBeanDefinition * @see org.springframework.beans.factory.BeanFactory#containsBean */ boolean containsSingleton(String beanName); /** * 获取所有单例bean的名称 * @return the list of names as a String array (never {@code null}) * @see #registerSingleton * @see org.springframework.beans.factory.support.BeanDefinitionRegistry#getBeanDefinitionNames * @see org.springframework.beans.factory.ListableBeanFactory#getBeanDefinitionNames */ String[] getSingletonNames(); /** * 获取所有单例bean的数量 * @return the number of singleton beans * @see #registerSingleton * @see org.springframework.beans.factory.support.BeanDefinitionRegistry#getBeanDefinitionCount * @see org.springframework.beans.factory.ListableBeanFactory#getBeanDefinitionCount */ int getSingletonCount(); /** * 获取互斥的对象 * @return the mutex object (never {@code null}) * @since 4.2 */ Object getSingletonMutex(); }
package org.springframework.beans.factory.support;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;
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.factory.BeanCreationException;
import org.springframework.beans.factory.BeanCreationNotAllowedException;
import org.springframework.beans.factory.BeanCurrentlyInCreationException;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.ObjectFactory;
import org.springframework.beans.factory.config.SingletonBeanRegistry;
import org.springframework.core.SimpleAliasRegistry;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
/**
* 默认单例注册表实现
* @author Juergen Hoeller
* @since 2.0
* @see #registerSingleton
* @see #registerDisposableBean
* @see org.springframework.beans.factory.DisposableBean
* @see org.springframework.beans.factory.config.ConfigurableBeanFactory
*/
public class DefaultSingletonBeanRegistry extends SimpleAliasRegistry implements SingletonBeanRegistry {
/**
* 并发map中不允许空，用空对象代替
*/
protected static final Object NULL_OBJECT = new Object();
/** Logger available to subclasses */
protected final Log logger = LogFactory.getLog(getClass());
/** 缓存所有的单例对象: bean name --> bean instance */
private final Map singletonObjects = new ConcurrentHashMap(256);
/** 缓存所有的objectFactory对象: bean name --> ObjectFactory */
private final Map> singletonFactories = new HashMap>(16);
/** 获取所有可以提前获取的对象（循环依赖的时候使用）: bean name --> bean instance */
private final Map earlySingletonObjects = new HashMap(16);
/** 所有已经注册的bean的name列表，有序的 */
private final Set registeredSingletons = new LinkedHashSet(256);
/** 所有正在创建的bean的名称 */
private final Set singletonsCurrentlyInCreation =Collections.newSetFromMap(new ConcurrentHashMap(16));
/** 所有被创建检查排除的bean列表 */
private final Set inCreationCheckExclusions =Collections.newSetFromMap(new ConcurrentHashMap(16));
/** bean管理过程中所有的被禁用的异常列表 */
private Set suppressedExceptions;
/** 标识当前是否处于销毁单例bean的时候 */
private boolean singletonsCurrentlyInDestruction = false;
/** Disposable bean 实例: bean name --> disposable instance */
private final Map disposableBeans = new LinkedHashMap();
/** bean和bean所包含的bean之间的关系: bean name --> Set of bean names that the bean contains */
private final Map> containedBeanMap = new ConcurrentHashMap>(16);
/** bean和bean所依赖的bean之间的关系: bean name --> Set of dependent bean names */
private final Map> dependentBeanMap = new ConcurrentHashMap>(64);
/** bean和依赖该bean的bean之间的关系: bean name --> Set of bean names for the bean's dependencies */
private final Map> dependenciesForBeanMap = new ConcurrentHashMap>(64);
@Override
public void registerSingleton(String beanName, Object singletonObject) throws IllegalStateException {
Assert.notNull(beanName, "'beanName' must not be null");
synchronized (this.singletonObjects) {
//如果该bean已经注册，抛出异常
Object oldObject = this.singletonObjects.get(beanName);
if (oldObject != null) {
throw new IllegalStateException("Could not register object [" + singletonObject +
"] under bean name '" + beanName + "': there is already object [" + oldObject + "] bound");
}
addSingleton(beanName, singletonObject);
}
}
/**
* 将bean添加到注册表中，singletonObjects、registeredSingletons缓存中添加，
* singletonFactories、earlySingletonObjects 缓存中删除
* To be called for eager registration of singletons.
* @param beanName the name of the bean
* @param singletonObject the singleton object
*/
protected void addSingleton(String beanName, Object singletonObject) {
synchronized (this.singletonObjects) {
this.singletonObjects.put(beanName, (singletonObject != null ? singletonObject : NULL_OBJECT));
this.singletonFactories.remove(beanName);
this.earlySingletonObjects.remove(beanName);
this.registeredSingletons.add(beanName);
}
}
/**
* 通过一个工厂对象添加一个往注册表中添加一个对象
* @param beanName the name of the bean
* @param singletonFactory the factory for the singleton object
*/
protected void addSingletonFactory(String beanName, ObjectFactory singletonFactory) {
Assert.notNull(singletonFactory, "Singleton factory must not be null");
synchronized (this.singletonObjects) {
if (!this.singletonObjects.containsKey(beanName)) {
this.singletonFactories.put(beanName, singletonFactory);
this.earlySingletonObjects.remove(beanName);
this.registeredSingletons.add(beanName);
}
}
}
@Override
public Object getSingleton(String beanName) {
return getSingleton(beanName, true);
}
/**
* 获取一个单例bean对象，是否允许创建之前获取一个对象
* @param beanName the name of the bean to look for
* @param allowEarlyReference whether early references should be created or not
* @return the registered singleton object, or {@code null} if none found
*/
protected Object getSingleton(String beanName, boolean allowEarlyReference) {
Object singletonObject = this.singletonObjects.get(beanName);
//如果已经创建的bean对象缓存中没有，并且当前bean正在创建
if (singletonObject == null && isSingletonCurrentlyInCreation(beanName)) {
synchronized (this.singletonObjects) {
//从可以提前获取的单例对象缓存中查找对象
singletonObject = this.earlySingletonObjects.get(beanName);
//如果没有创建，并且允许提前获取对象
if (singletonObject == null && allowEarlyReference) {
//就从工厂bean缓存中获取bean的工厂类
ObjectFactory singletonFactory = this.singletonFactories.get(beanName);
//如果工厂类不为空，就通过工厂类创建一个单例对象，并将该单例对象放到提前获取的单例缓存中，
//并从工厂bean缓存中移除
if (singletonFactory != null) {
singletonObject = singletonFactory.getObject();
this.earlySingletonObjects.put(beanName, singletonObject);
this.singletonFactories.remove(beanName);
}
}
}
}
return (singletonObject != NULL_OBJECT ? singletonObject : null);
}
/**
* 通过一个工厂bean获取一个bean对象
* @param beanName the name of the bean
* @param singletonFactory the ObjectFactory to lazily create the singleton
* with, if necessary
* @return the registered singleton object
*/
public Object getSingleton(String beanName, ObjectFactory singletonFactory) {
Assert.notNull(beanName, "'beanName' must not be null");
synchronized (this.singletonObjects) {
Object singletonObject = this.singletonObjects.get(beanName);
if (singletonObject == null) {
if (this.singletonsCurrentlyInDestruction) {
throw new BeanCreationNotAllowedException(beanName,
"Singleton bean creation not allowed while singletons of this factory are in destruction " +
"(Do not request a bean from a BeanFactory in a destroy method implementation!)");
}
if (logger.isDebugEnabled()) {
logger.debug("Creating shared instance of singleton bean '" + beanName + "'");
}
//bean的前处理器
beforeSingletonCreation(beanName);
boolean newSingleton = false;
boolean recordSuppressedExceptions = (this.suppressedExceptions == null);
if (recordSuppressedExceptions) {
this.suppressedExceptions = new LinkedHashSet();
}
try {
singletonObject = singletonFactory.getObject();
newSingleton = true;
}
catch (IllegalStateException ex) {
// Has the singleton object implicitly appeared in the meantime ->
// if yes, proceed with it since the exception indicates that state.
singletonObject = this.singletonObjects.get(beanName);
if (singletonObject == null) {
throw ex;
}
}
catch (BeanCreationException ex) {
if (recordSuppressedExceptions) {
for (Exception suppressedException : this.suppressedExceptions) {
ex.addRelatedCause(suppressedException);
}
}
throw ex;
}
finally {
if (recordSuppressedExceptions) {
this.suppressedExceptions = null;
}
//bean的后处理器
afterSingletonCreation(beanName);
}
if (newSingleton) {
addSingleton(beanName, singletonObject);
}
}
return (singletonObject != NULL_OBJECT ? singletonObject : null);
}
}
/**
* 存放bean创建过程的异常
* @param ex the Exception to register
*/
protected void onSuppressedException(Exception ex) {
synchronized (this.singletonObjects) {
if (this.suppressedExceptions != null) {
this.suppressedExceptions.add(ex);
}
}
}
/**
* 移除一个单例bean
* @param beanName the name of the bean
* @see #getSingletonMutex()
*/
protected void removeSingleton(String beanName) {
synchronized (this.singletonObjects) {
this.singletonObjects.remove(beanName);
this.singletonFactories.remove(beanName);
this.earlySingletonObjects.remove(beanName);
this.registeredSingletons.remove(beanName);
}
}
@Override
public boolean containsSingleton(String beanName) {
return this.singletonObjects.containsKey(beanName);
}
@Override
public String[] getSingletonNames() {
synchronized (this.singletonObjects) {
return StringUtils.toStringArray(this.registeredSingletons);
}
}
@Override
public int getSingletonCount() {
synchronized (this.singletonObjects) {
return this.registeredSingletons.size();
}
}
public void setCurrentlyInCreation(String beanName, boolean inCreation) {
Assert.notNull(beanName, "Bean name must not be null");
if (!inCreation) {
this.inCreationCheckExclusions.add(beanName);
}
else {
this.inCreationCheckExclusions.remove(beanName);
}
}
public boolean isCurrentlyInCreation(String beanName) {
Assert.notNull(beanName, "Bean name must not be null");
return (!this.inCreationCheckExclusions.contains(beanName) && isActuallyInCreation(beanName));
}
protected boolean isActuallyInCreation(String beanName) {
return isSingletonCurrentlyInCreation(beanName);
}
/**
* Return whether the specified singleton bean is currently in creation
* (within the entire factory).
* @param beanName the name of the bean
*/
public boolean isSingletonCurrentlyInCreation(String beanName) {
return this.singletonsCurrentlyInCreation.contains(beanName);
}
/**
* Callback before singleton creation.
* The default implementation register the singleton as currently in creation.
* @param beanName the name of the singleton about to be created
* @see #isSingletonCurrentlyInCreation
*/
protected void beforeSingletonCreation(String beanName) {
if (!this.inCreationCheckExclusions.contains(beanName) && !this.singletonsCurrentlyInCreation.add(beanName)) {
throw new BeanCurrentlyInCreationException(beanName);
}
}
/**
* Callback after singleton creation.
*
The default implementation marks the singleton as not in creation anymore.
* @param beanName the name of the singleton that has been created
* @see #isSingletonCurrentlyInCreation
*/
protected void afterSingletonCreation(String beanName) {
if (!this.inCreationCheckExclusions.contains(beanName) && !this.singletonsCurrentlyInCreation.remove(beanName)) {
throw new IllegalStateException("Singleton '" + beanName + "' isn't currently in creation");
}
}
/**
* 注册一个可销毁的bean
* @param beanName the name of the bean
* @param bean the bean instance
*/
public void registerDisposableBean(String beanName, DisposableBean bean) {
synchronized (this.disposableBeans) {
this.disposableBeans.put(beanName, bean);
}
}
/**
* 注册一个包含内部bean和外部bean的bean对象
* @param containedBeanName the name of the contained (inner) bean
* @param containingBeanName the name of the containing (outer) bean
* @see #registerDependentBean
*/
public void registerContainedBean(String containedBeanName, String containingBeanName) {
// A quick check for an existing entry upfront, avoiding synchronization...
Set containedBeans = this.containedBeanMap.get(containingBeanName);
if (containedBeans != null && containedBeans.contains(containedBeanName)) {
return;
}
// No entry yet -> fully synchronized manipulation of the containedBeans Set
synchronized (this.containedBeanMap) {
containedBeans = this.containedBeanMap.get(containingBeanName);
if (containedBeans == null) {
containedBeans = new LinkedHashSet(8);
this.containedBeanMap.put(containingBeanName, containedBeans);
}
containedBeans.add(containedBeanName);
}
registerDependentBean(containedBeanName, containingBeanName);
}
/**
* 注册一个bean和他依赖的bean
* @param beanName the name of the bean
* @param dependentBeanName the name of the dependent bean
*/
public void registerDependentBean(String beanName, String dependentBeanName) {
// A quick check for an existing entry upfront, avoiding synchronization...
String canonicalName = canonicalName(beanName);
Set dependentBeans = this.dependentBeanMap.get(canonicalName);
if (dependentBeans != null && dependentBeans.contains(dependentBeanName)) {
return;
}
// No entry yet -> fully synchronized manipulation of the dependentBeans Set
synchronized (this.dependentBeanMap) {
dependentBeans = this.dependentBeanMap.get(canonicalName);
if (dependentBeans == null) {
dependentBeans = new LinkedHashSet(8);
this.dependentBeanMap.put(canonicalName, dependentBeans);
}
dependentBeans.add(dependentBeanName);
}
synchronized (this.dependenciesForBeanMap) {
Set dependenciesForBean = this.dependenciesForBeanMap.get(dependentBeanName);
if (dependenciesForBean == null) {
dependenciesForBean = new LinkedHashSet(8);
this.dependenciesForBeanMap.put(dependentBeanName, dependenciesForBean);
}
dependenciesForBean.add(canonicalName);
}
}
/**
* 判断两个bean是否相互依赖
* @param beanName the name of the bean to check
* @param dependentBeanName the name of the dependent bean
* @since 4.0
*/
protected boolean isDependent(String beanName, String dependentBeanName) {
return isDependent(beanName, dependentBeanName, null);
}
private boolean isDependent(String beanName, String dependentBeanName, Set alreadySeen) {
if (alreadySeen != null && alreadySeen.contains(beanName)) {
return false;
}
String canonicalName = canonicalName(beanName);
Set dependentBeans = this.dependentBeanMap.get(canonicalName);
if (dependentBeans == null) {
return false;
}
if (dependentBeans.contains(dependentBeanName)) {
return true;
}
for (String transitiveDependency : dependentBeans) {
if (alreadySeen == null) {
alreadySeen = new HashSet();
}
alreadySeen.add(beanName);
if (isDependent(transitiveDependency, dependentBeanName, alreadySeen)) {
return true;
}
}
return false;
}
/**
* 确认当前bean是否有依赖
* @param beanName the name of the bean to check
*/
protected boolean hasDependentBean(String beanName) {
return this.dependentBeanMap.containsKey(beanName);
}
/**
* 获取这个bean所有依赖的bean
* @param beanName the name of the bean
* @return the array of dependent bean names, or an empty array if none
*/
public String[] getDependentBeans(String beanName) {
Set dependentBeans = this.dependentBeanMap.get(beanName);
if (dependentBeans == null) {
return new String[0];
}
return StringUtils.toStringArray(dependentBeans);
}
/**
* 返回所有依赖该bean的bean对象
* @param beanName the name of the bean
* @return the array of names of beans which the bean depends on,
* or an empty array if none
*/
public String[] getDependenciesForBean(String beanName) {
Set dependenciesForBean = this.dependenciesForBeanMap.get(beanName);
if (dependenciesForBean == null) {
return new String[0];
}
return dependenciesForBean.toArray(new String[dependenciesForBean.size()]);
}
public void destroySingletons() {
if (logger.isDebugEnabled()) {
logger.debug("Destroying singletons in " + this);
}
synchronized (this.singletonObjects) {
this.singletonsCurrentlyInDestruction = true;
}
String[] disposableBeanNames;
synchronized (this.disposableBeans) {
disposableBeanNames = StringUtils.toStringArray(this.disposableBeans.keySet());
}
for (int i = disposableBeanNames.length - 1; i >= 0; i--) {
destroySingleton(disposableBeanNames[i]);
}
this.containedBeanMap.clear();
this.dependentBeanMap.clear();
this.dependenciesForBeanMap.clear();
synchronized (this.singletonObjects) {
this.singletonObjects.clear();
this.singletonFactories.clear();
this.earlySingletonObjects.clear();
this.registeredSingletons.clear();
this.singletonsCurrentlyInDestruction = false;
}
}
/**
* Destroy the given bean. Delegates to {@code destroyBean}
* if a corresponding disposable bean instance is found.
* @param beanName the name of the bean
* @see #destroyBean
*/
public void destroySingleton(String beanName) {
// Remove a registered singleton of the given name, if any.
removeSingleton(beanName);
// Destroy the corresponding DisposableBean instance.
DisposableBean disposableBean;
synchronized (this.disposableBeans) {
disposableBean = (DisposableBean) this.disposableBeans.remove(beanName);
}
destroyBean(beanName, disposableBean);
}
/**
* Destroy the given bean. Must destroy beans that depend on the given
* bean before the bean itself. Should not throw any exceptions.
* @param beanName the name of the bean
* @param bean the bean instance to destroy
*/
protected void destroyBean(String beanName, DisposableBean bean) {
// Trigger destruction of dependent beans first...
Set dependencies = this.dependentBeanMap.remove(beanName);
if (dependencies != null) {
if (logger.isDebugEnabled()) {
logger.debug("Retrieved dependent beans for bean '" + beanName + "': " + dependencies);
}
for (String dependentBeanName : dependencies) {
destroySingleton(dependentBeanName);
}
}
// Actually destroy the bean now...
if (bean != null) {
try {
bean.destroy();
}
catch (Throwable ex) {
logger.error("Destroy method on bean with name '" + beanName + "' threw an exception", ex);
}
}
// Trigger destruction of contained beans...
Set containedBeans = this.containedBeanMap.remove(beanName);
if (containedBeans != null) {
for (String containedBeanName : containedBeans) {
destroySingleton(containedBeanName);
}
}
// Remove destroyed bean from other beans' dependencies.
synchronized (this.dependentBeanMap) {
for (Iterator>> it = this.dependentBeanMap.entrySet().iterator(); it.hasNext();) {
Map.Entry> entry = it.next();
Set dependenciesToClean = entry.getValue();
dependenciesToClean.remove(beanName);
if (dependenciesToClean.isEmpty()) {
it.remove();
}
}
}
// Remove destroyed bean's prepared dependency information.
this.dependenciesForBeanMap.remove(beanName);
}
/**
* Exposes the singleton mutex to subclasses and external collaborators.
* Subclasses should synchronize on the given Object if they perform
* any sort of extended singleton creation phase. In particular, subclasses
* should not have their own mutexes involved in singleton creation,
* to avoid the potential for deadlocks in lazy-init situations.
*/
public final Object getSingletonMutex() {
return this.singletonObjects;
}
}