org.springframework.aop.framework

Class ProxyFactoryBean

java.lang.Object

org.springframework.aop.framework.ProxyConfig

org.springframework.aop.framework.AdvisedSupport

org.springframework.aop.framework.ProxyCreatorSupport

org.springframework.aop.framework.ProxyFactoryBean

All Implemented Interfaces:

java.io.Serializable, Advised, TargetClassAware, Aware, BeanClassLoaderAware, BeanFactoryAware, FactoryBean<java.lang.Object>

public class ProxyFactoryBean
extends ProxyCreatorSupport
implements FactoryBean<java.lang.Object>, BeanClassLoaderAware, BeanFactoryAware

FactoryBean implementation that builds an AOP proxy based on beans in Spring BeanFactory.

MethodInterceptors and Advisors are identified by a list of bean names in the current bean factory, specified through the "interceptorNames" property. The last entry in the list can be the name of a target bean or a TargetSource; however, it is normally preferable to use the "targetName"/"target"/"targetSource" properties instead.

Global interceptors and advisors can be added at the factory level. The specified ones are expanded in an interceptor list where an "xxx*" entry is included in the list, matching the given prefix with the bean names (e.g. "global*" would match both "globalBean1" and "globalBean2", "*" all defined interceptors). The matching interceptors get applied according to their returned order value, if they implement the Ordered interface.

Creates a JDK proxy when proxy interfaces are given, and a CGLIB proxy for the actual target class if not. Note that the latter will only work if the target class does not have final methods, as a dynamic subclass will be created at runtime.

It's possible to cast a proxy obtained from this factory to Advised, or to obtain the ProxyFactoryBean reference and programmatically manipulate it. This won't work for existing prototype references, which are independent. However, it will work for prototypes subsequently obtained from the factory. Changes to interception will work immediately on singletons (including existing references). However, to change interfaces or target it's necessary to obtain a new instance from the factory. This means that singleton instances obtained from the factory do not have the same object identity. However, they do have the same interceptors and target, and changing any reference will change all objects.

Author:

Rod Johnson, Juergen Hoeller

See Also:

setInterceptorNames(java.lang.String...), setProxyInterfaces(java.lang.Class<?>[]), org.aopalliance.intercept.MethodInterceptor, Advisor, Advised, Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private static class	ProxyFactoryBean.PrototypePlaceholderAdvisor Used in the interceptor chain where we need to replace a bean with a prototype on creating a proxy.

Field Summary

Fields

Modifier and Type	Field and Description
private AdvisorAdapterRegistry	advisorAdapterRegistry
private boolean	advisorChainInitialized Whether the advisor chain has already been initialized
private boolean	autodetectInterfaces
private BeanFactory	beanFactory
private boolean	classLoaderConfigured
private boolean	freezeProxy
static java.lang.String	GLOBAL_SUFFIX This suffix in a value in an interceptor list indicates to expand globals.
private java.lang.String[]	interceptorNames
protected Log	logger
private java.lang.ClassLoader	proxyClassLoader
private boolean	singleton
private java.lang.Object	singletonInstance If this is a singleton, the cached singleton proxy instance
private java.lang.String	targetName

Fields inherited from class org.springframework.aop.framework.AdvisedSupport

advisorChainFactory, EMPTY_TARGET_SOURCE, targetSource

Fields inherited from class org.springframework.aop.framework.ProxyConfig

exposeProxy, opaque

Constructor Summary

Constructors

Constructor and Description
ProxyFactoryBean()

Method Summary

Modifier and Type	Method and Description
private void	addAdvisorOnChainCreation(java.lang.Object next, java.lang.String name) Invoked when advice chain is created.
private void	addGlobalAdvisor(ListableBeanFactory beanFactory, java.lang.String prefix) Add all global interceptors and pointcuts.
protected void	adviceChanged() Blow away and recache singleton on an advice change.
private void	checkInterceptorNames() Check the interceptorNames list whether it contains a target name as final element.
protected java.lang.Class<?>	createCompositeInterface(java.lang.Class<?>[] interfaces) Create a composite interface Class for the given interfaces, implementing the given interfaces in one single Class.
private java.util.List<Advisor>	freshAdvisorChain() Return an independent advisor chain.
private TargetSource	freshTargetSource() Return a TargetSource to use when creating a proxy.
java.lang.Object	getObject() Return a proxy.
java.lang.Class<?>	getObjectType() Return the type of the proxy.
protected java.lang.Object	getProxy(AopProxy aopProxy) Return the proxy object to expose.
private java.lang.Object	getSingletonInstance() Return the singleton instance of this class's proxy object, lazily creating it if it hasn't been created already.
private void	initializeAdvisorChain() Create the advisor (interceptor) chain.
private boolean	isNamedBeanAnAdvisorOrAdvice(java.lang.String beanName) Look at bean factory metadata to work out whether this bean name, which concludes the interceptorNames list, is an Advisor or Advice, or may be a target.
boolean	isSingleton() Is the object managed by this factory a singleton? That is, will FactoryBean.getObject() always return the same object (a reference that can be cached)?
private Advisor	namedBeanToAdvisor(java.lang.Object next) Convert the following object sourced from calling getBean() on a name in the interceptorNames array to an Advisor or TargetSource.
private java.lang.Object	newPrototypeInstance() Create a new prototype instance of this class's created proxy object, backed by an independent AdvisedSupport configuration.
private void	readObject(java.io.ObjectInputStream ois)
void	setAdvisorAdapterRegistry(AdvisorAdapterRegistry advisorAdapterRegistry) Specify the AdvisorAdapterRegistry to use.
void	setAutodetectInterfaces(boolean autodetectInterfaces) Set whether to autodetect proxy interfaces if none specified.
void	setBeanClassLoader(java.lang.ClassLoader classLoader) Callback that supplies the bean class loader to a bean instance.
void	setBeanFactory(BeanFactory beanFactory) Callback that supplies the owning factory to a bean instance.
void	setFrozen(boolean frozen) Set whether this config should be frozen.
void	setInterceptorNames(java.lang.String... interceptorNames) Set the list of Advice/Advisor bean names.
void	setProxyClassLoader(java.lang.ClassLoader classLoader) Set the ClassLoader to generate the proxy class in.
void	setProxyInterfaces(java.lang.Class<?>[] proxyInterfaces) Set the names of the interfaces we're proxying.
void	setSingleton(boolean singleton) Set the value of the singleton property.
void	setTargetName(java.lang.String targetName) Set the name of the target bean.

Methods inherited from class org.springframework.aop.framework.ProxyCreatorSupport

addListener, createAopProxy, getAopProxyFactory, isActive, removeListener, setAopProxyFactory

Methods inherited from class org.springframework.aop.framework.AdvisedSupport

addAdvice, addAdvice, addAdvisor, addAdvisor, addAdvisors, addAdvisors, addInterface, adviceIncluded, copyConfigurationFrom, copyConfigurationFrom, countAdvicesOfType, getAdvisorChainFactory, getAdvisors, getAdvisorsInternal, getConfigurationOnlyCopy, getInterceptorsAndDynamicInterceptionAdvice, getProxiedInterfaces, getTargetClass, getTargetSource, indexOf, indexOf, isInterfaceProxied, isPreFiltered, removeAdvice, removeAdvisor, removeAdvisor, removeInterface, replaceAdvisor, setAdvisorChainFactory, setInterfaces, setPreFiltered, setTarget, setTargetClass, setTargetSource, toProxyConfigString, toString, updateAdvisorArray

Methods inherited from class org.springframework.aop.framework.ProxyConfig

copyFrom, isExposeProxy, isFrozen, isOpaque, isOptimize, isProxyTargetClass, setExposeProxy, setOpaque, setOptimize, setProxyTargetClass

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.springframework.aop.framework.Advised

isExposeProxy, isFrozen, isProxyTargetClass, setExposeProxy

Field Detail

GLOBAL_SUFFIX

public static final java.lang.String GLOBAL_SUFFIX

This suffix in a value in an interceptor list indicates to expand globals.

See Also:

Constant Field Values

logger

protected final Log logger

interceptorNames

private java.lang.String[] interceptorNames

targetName

private java.lang.String targetName

autodetectInterfaces

private boolean autodetectInterfaces

singleton

private boolean singleton

advisorAdapterRegistry

private AdvisorAdapterRegistry advisorAdapterRegistry

freezeProxy

private boolean freezeProxy

proxyClassLoader

private transient java.lang.ClassLoader proxyClassLoader

classLoaderConfigured

private transient boolean classLoaderConfigured

beanFactory

private transient BeanFactory beanFactory

advisorChainInitialized

private boolean advisorChainInitialized

Whether the advisor chain has already been initialized

singletonInstance

private java.lang.Object singletonInstance

If this is a singleton, the cached singleton proxy instance

Constructor Detail

ProxyFactoryBean

public ProxyFactoryBean()

Method Detail

setProxyInterfaces

public void setProxyInterfaces(java.lang.Class<?>[] proxyInterfaces)
                        throws java.lang.ClassNotFoundException

Set the names of the interfaces we're proxying. If no interface is given, a CGLIB for the actual class will be created.

This is essentially equivalent to the "setInterfaces" method, but mirrors TransactionProxyFactoryBean's "setProxyInterfaces".

Throws:

java.lang.ClassNotFoundException

See Also:

AdvisedSupport.setInterfaces(java.lang.Class<?>...), AbstractSingletonProxyFactoryBean.setProxyInterfaces(java.lang.Class<?>[])

setInterceptorNames

public void setInterceptorNames(java.lang.String... interceptorNames)

Set the list of Advice/Advisor bean names. This must always be set to use this factory bean in a bean factory.

The referenced beans should be of type Interceptor, Advisor or Advice The last entry in the list can be the name of any bean in the factory. If it's neither an Advice nor an Advisor, a new SingletonTargetSource is added to wrap it. Such a target bean cannot be used if the "target" or "targetSource" or "targetName" property is set, in which case the "interceptorNames" array must contain only Advice/Advisor bean names.

NOTE: Specifying a target bean as final name in the "interceptorNames" list is deprecated and will be removed in a future Spring version. Use the "targetName" property instead.

See Also:

org.aopalliance.intercept.MethodInterceptor, Advisor, org.aopalliance.aop.Advice, SingletonTargetSource

setTargetName

public void setTargetName(java.lang.String targetName)

Set the name of the target bean. This is an alternative to specifying the target name at the end of the "interceptorNames" array.

You can also specify a target object or a TargetSource object directly, via the "target"/"targetSource" property, respectively.

See Also:

setInterceptorNames(String[]), AdvisedSupport.setTarget(Object), AdvisedSupport.setTargetSource(org.springframework.aop.TargetSource)

setAutodetectInterfaces

public void setAutodetectInterfaces(boolean autodetectInterfaces)

Set whether to autodetect proxy interfaces if none specified.

Default is "true". Turn this flag off to create a CGLIB proxy for the full target class if no interfaces specified.

See Also:

ProxyConfig.setProxyTargetClass(boolean)

setSingleton

public void setSingleton(boolean singleton)

Set the value of the singleton property. Governs whether this factory should always return the same proxy instance (which implies the same target) or whether it should return a new prototype instance, which implies that the target and interceptors may be new instances also, if they are obtained from prototype bean definitions. This allows for fine control of independence/uniqueness in the object graph.

setAdvisorAdapterRegistry

public void setAdvisorAdapterRegistry(AdvisorAdapterRegistry advisorAdapterRegistry)

Specify the AdvisorAdapterRegistry to use. Default is the global AdvisorAdapterRegistry.

See Also:

GlobalAdvisorAdapterRegistry

setFrozen

public void setFrozen(boolean frozen)

Description copied from class: ProxyConfig

Set whether this config should be frozen.

When a config is frozen, no advice changes can be made. This is useful for optimization, and useful when we don't want callers to be able to manipulate configuration after casting to Advised.

Overrides:

setFrozen in class ProxyConfig

setProxyClassLoader

public void setProxyClassLoader(java.lang.ClassLoader classLoader)

Set the ClassLoader to generate the proxy class in.

Default is the bean ClassLoader, i.e. the ClassLoader used by the containing BeanFactory for loading all bean classes. This can be overridden here for specific proxies.

setBeanClassLoader

public void setBeanClassLoader(java.lang.ClassLoader classLoader)

Description copied from interface: BeanClassLoaderAware

Callback that supplies the bean class loader to a bean instance.

Invoked after the population of normal bean properties but before an initialization callback such as InitializingBean's InitializingBean.afterPropertiesSet() method or a custom init-method.

Specified by:

setBeanClassLoader in interface BeanClassLoaderAware

Parameters:

classLoader - the owning class loader; may be null in which case a default ClassLoader must be used, for example the ClassLoader obtained via ClassUtils.getDefaultClassLoader()

setBeanFactory

public void setBeanFactory(BeanFactory beanFactory)

Description copied from interface: BeanFactoryAware

Callback that supplies the owning factory to a bean instance.

Invoked after the population of normal bean properties but before an initialization callback such as InitializingBean.afterPropertiesSet() or a custom init-method.

Specified by:

setBeanFactory in interface BeanFactoryAware

Parameters:

beanFactory - owning BeanFactory (never null). The bean can immediately call methods on the factory.

See Also:

BeanInitializationException

getObject

public java.lang.Object getObject()
                           throws BeansException

Return a proxy. Invoked when clients obtain beans from this factory bean. Create an instance of the AOP proxy to be returned by this factory. The instance will be cached for a singleton, and create on each call to getObject() for a proxy.

Specified by:

getObject in interface FactoryBean<java.lang.Object>

Returns:

a fresh AOP proxy reflecting the current state of this factory

Throws:

BeansException

See Also:

FactoryBeanNotInitializedException

getObjectType

public java.lang.Class<?> getObjectType()

Return the type of the proxy. Will check the singleton instance if already created, else fall back to the proxy interface (in case of just a single one), the target bean type, or the TargetSource's target class.

Specified by:

getObjectType in interface FactoryBean<java.lang.Object>

Returns:

the type of object that this FactoryBean creates, or null if not known at the time of the call

See Also:

TargetSource.getTargetClass()

isSingleton

public boolean isSingleton()

Description copied from interface: FactoryBean

Is the object managed by this factory a singleton? That is, will FactoryBean.getObject() always return the same object (a reference that can be cached)?

NOTE: If a FactoryBean indicates to hold a singleton object, the object returned from getObject() might get cached by the owning BeanFactory. Hence, do not return true unless the FactoryBean always exposes the same reference.

The singleton status of the FactoryBean itself will generally be provided by the owning BeanFactory; usually, it has to be defined as singleton there.

NOTE: This method returning false does not necessarily indicate that returned objects are independent instances. An implementation of the extended SmartFactoryBean interface may explicitly indicate independent instances through its SmartFactoryBean.isPrototype() method. Plain FactoryBean implementations which do not implement this extended interface are simply assumed to always return independent instances if the isSingleton() implementation returns false.

Specified by:

isSingleton in interface FactoryBean<java.lang.Object>

Returns:

whether the exposed object is a singleton

See Also:

FactoryBean.getObject(), SmartFactoryBean.isPrototype()

createCompositeInterface

protected java.lang.Class<?> createCompositeInterface(java.lang.Class<?>[] interfaces)

Create a composite interface Class for the given interfaces, implementing the given interfaces in one single Class.

The default implementation builds a JDK proxy class for the given interfaces.

Parameters:

interfaces - the interfaces to merge

Returns:

the merged interface as Class

See Also:

Proxy.getProxyClass(java.lang.ClassLoader, java.lang.Class<?>...)

getSingletonInstance

private java.lang.Object getSingletonInstance()

Return the singleton instance of this class's proxy object, lazily creating it if it hasn't been created already.

Returns:

the shared singleton proxy

newPrototypeInstance

private java.lang.Object newPrototypeInstance()

Create a new prototype instance of this class's created proxy object, backed by an independent AdvisedSupport configuration.

Returns:

a totally independent proxy, whose advice we may manipulate in isolation

getProxy

protected java.lang.Object getProxy(AopProxy aopProxy)

Return the proxy object to expose.

The default implementation uses a getProxy call with the factory's bean class loader. Can be overridden to specify a custom class loader.

Parameters:

aopProxy - the prepared AopProxy instance to get the proxy from

Returns:

the proxy object to expose

See Also:

AopProxy.getProxy(ClassLoader)

checkInterceptorNames

private void checkInterceptorNames()

Check the interceptorNames list whether it contains a target name as final element. If found, remove the final name from the list and set it as targetName.

isNamedBeanAnAdvisorOrAdvice

private boolean isNamedBeanAnAdvisorOrAdvice(java.lang.String beanName)

Look at bean factory metadata to work out whether this bean name, which concludes the interceptorNames list, is an Advisor or Advice, or may be a target.

Parameters:

beanName - bean name to check

Returns:

true if it's an Advisor or Advice

initializeAdvisorChain

private void initializeAdvisorChain()
                             throws AopConfigException,
                                    BeansException

Create the advisor (interceptor) chain. Advisors that are sourced from a BeanFactory will be refreshed each time a new prototype instance is added. Interceptors added programmatically through the factory API are unaffected by such changes.

Throws:

AopConfigException

BeansException

freshAdvisorChain

private java.util.List<Advisor> freshAdvisorChain()

Return an independent advisor chain. We need to do this every time a new prototype instance is returned, to return distinct instances of prototype Advisors and Advices.

addGlobalAdvisor

private void addGlobalAdvisor(ListableBeanFactory beanFactory,
                              java.lang.String prefix)

Add all global interceptors and pointcuts.

addAdvisorOnChainCreation

private void addAdvisorOnChainCreation(java.lang.Object next,
                                       java.lang.String name)

Invoked when advice chain is created.

Add the given advice, advisor or object to the interceptor list. Because of these three possibilities, we can't type the signature more strongly.

Parameters:

next - advice, advisor or target object

name - bean name from which we obtained this object in our owning bean factory

freshTargetSource

private TargetSource freshTargetSource()

Return a TargetSource to use when creating a proxy. If the target was not specified at the end of the interceptorNames list, the TargetSource will be this class's TargetSource member. Otherwise, we get the target bean and wrap it in a TargetSource if necessary.

namedBeanToAdvisor

private Advisor namedBeanToAdvisor(java.lang.Object next)

Convert the following object sourced from calling getBean() on a name in the interceptorNames array to an Advisor or TargetSource.

adviceChanged

protected void adviceChanged()

Blow away and recache singleton on an advice change.

Overrides:

adviceChanged in class ProxyCreatorSupport

See Also:

AdvisedSupportListener.adviceChanged(org.springframework.aop.framework.AdvisedSupport)

readObject

private void readObject(java.io.ObjectInputStream ois)
                 throws java.io.IOException,
                        java.lang.ClassNotFoundException

Throws:

java.io.IOException

java.lang.ClassNotFoundException