org.springframework.aop.framework
Class AopContext

java.lang.Object
  org.springframework.aop.framework.AopContext

public abstract class AopContext
extends java.lang.Object

Class containing static methods used to obtain information about the current AOP invocation.

The currentProxy() method is usable if the AOP framework is configured to expose the current proxy (not the default). It returns the AOP proxy in use. Target objects or advice can use this to make advised calls, in the same way as getEJBObject() can be used in EJBs. They can also use it to find advice configuration.

Spring's AOP framework does not expose proxies by default, as there is a performance cost in doing so.

The functionality in this class might be used by a target object that needed access to resources on the invocation. However, this approach should not be used when there is a reasonable alternative, as it makes application code dependent on usage under AOP and the Spring AOP framework in particular.

Since:

13.03.2003

Author:

Rod Johnson, Juergen Hoeller

Field Summary

private static java.lang.ThreadLocal<java.lang.Object>

currentProxy ThreadLocal holder for AOP proxy associated with this thread.

Constructor Summary

AopContext()

Method Summary

static java.lang.Object	currentProxy() Try to return the current AOP proxy.
(package private) static java.lang.Object	setCurrentProxy(java.lang.Object proxy) Make the given proxy available via the currentProxy() method.

Methods inherited from class java.lang.Object

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

Field Detail

currentProxy

private static final java.lang.ThreadLocal<java.lang.Object> currentProxy

ThreadLocal holder for AOP proxy associated with this thread. Will contain null unless the "exposeProxy" property on the controlling proxy configuration has been set to "true".

See Also:

ProxyConfig.setExposeProxy(boolean)

Constructor Detail

AopContext

public AopContext()

Method Detail

currentProxy

public static java.lang.Object currentProxy()
                                     throws java.lang.IllegalStateException

Try to return the current AOP proxy. This method is usable only if the calling method has been invoked via AOP, and the AOP framework has been set to expose proxies. Otherwise, this method will throw an IllegalStateException.

Returns:

Object the current AOP proxy (never returns null)

Throws:

java.lang.IllegalStateException - if the proxy cannot be found, because the method was invoked outside an AOP invocation context, or because the AOP framework has not been configured to expose the proxy

setCurrentProxy

static java.lang.Object setCurrentProxy(java.lang.Object proxy)

Make the given proxy available via the currentProxy() method.

Note that the caller should be careful to keep the old value as appropriate.

Parameters:

proxy - the proxy to expose (or null to reset it)

Returns:

the old proxy, which may be null if none was bound

See Also:

currentProxy()