ProxyFactoryBean (Spring Framework 3.2.1.RELEASE API)
Date: 2013-01-24

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:
    Serializable, Advised, TargetClassAware, Aware, BeanClassLoaderAware, BeanFactoryAware, FactoryBean<Object>

      public class ProxyFactoryBean
      extends ProxyCreatorSupport
      implements FactoryBean<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[])`, `MethodInterceptor`, `Advisor`, `Advised`, Serialized Form

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `static String` | `GLOBAL_SUFFIX` This suffix in a value in an interceptor list indicates to expand globals.
    `protected Log` | `logger`

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

      `EMPTY_TARGET_SOURCE`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `ProxyFactoryBean()`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `protected void` | `adviceChanged()` Blow away and recache singleton on an advice change.
    `protected Class` | `createCompositeInterface(Class[] interfaces)` Create a composite interface Class for the given interfaces, implementing the given interfaces in one single Class.
    `Object` | `getObject()` Return a proxy.
    `Class<?>` | `getObjectType()` Return the type of the proxy.
    `protected Object` | `getProxy(AopProxy aopProxy)` Return the proxy object to expose.
    `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)?
    `void` | `setAdvisorAdapterRegistry(AdvisorAdapterRegistry advisorAdapterRegistry)` Specify the AdvisorAdapterRegistry to use.
    `void` | `setAutodetectInterfaces(boolean autodetectInterfaces)` Set whether to autodetect proxy interfaces if none specified.
    `void` | `setBeanClassLoader(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(String[] interceptorNames)` Set the list of Advice/Advisor bean names.
    `void` | `setProxyClassLoader(ClassLoader classLoader)` Set the ClassLoader to generate the proxy class in.
    `void` | `setProxyInterfaces(Class[] proxyInterfaces)` Set the names of the interfaces we're proxying.
    `void` | `setSingleton(boolean singleton)` Set the value of the singleton property.
    `void` | `setTargetName(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, addAllAdvisors, addInterface, adviceIncluded, copyConfigurationFrom, copyConfigurationFrom, countAdvicesOfType, getAdvisorChainFactory, getAdvisors, getAdvisorsInternal, 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 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

  - ### Constructor Detail

    - #### ProxyFactoryBean

          public ProxyFactoryBean()

  - ### Method Detail

    - #### setProxyInterfaces

          public void setProxyInterfaces(Class[] proxyInterfaces)
                                  throws 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:
        `ClassNotFoundException`
      See Also:
        `AdvisedSupport.setInterfaces(java.lang.Class[])`, `AbstractSingletonProxyFactoryBean.setProxyInterfaces(java.lang.Class<?>[])`

    - #### setInterceptorNames

          public void setInterceptorNames(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:
        `MethodInterceptor`, `Advisor`, `Advice`, `SingletonTargetSource`

    - #### setTargetName

          public void setTargetName(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(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(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 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<Object>`
      Returns:
        a fresh AOP proxy reflecting the current state of this factory
      Throws:
        `BeansException`
      See Also:
        `FactoryBeanNotInitializedException`

    - #### getObjectType

          public 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<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<Object>`
      Returns:
        whether the exposed object is a singleton
      See Also:
        `FactoryBean.getObject()`, `SmartFactoryBean.isPrototype()`

    - #### createCompositeInterface

          protected Class createCompositeInterface(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<?>...)`

    - #### getProxy

          protected 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)`

    - #### 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)`