org.springframework.context.annotation

Class ConfigurationClassEnhancer.BeanMethodInterceptor

java.lang.Object

org.springframework.context.annotation.ConfigurationClassEnhancer.BeanMethodInterceptor

All Implemented Interfaces:

ConfigurationClassEnhancer.ConditionalCallback

Enclosing class:

ConfigurationClassEnhancer

private static class ConfigurationClassEnhancer.BeanMethodInterceptor
extends java.lang.Object
implements ConfigurationClassEnhancer.ConditionalCallback

Intercepts the invocation of any Bean-annotated methods in order to ensure proper handling of bean semantics such as scoping and AOP proxying.

See Also:

Bean, ConfigurationClassEnhancer

Constructor Summary

Constructors

Modifier	Constructor and Description
private	BeanMethodInterceptor()

Method Summary

Modifier and Type	Method and Description
private java.lang.Object	enhanceFactoryBean(java.lang.Object factoryBean, ConfigurableBeanFactory beanFactory, java.lang.String beanName) Create a subclass proxy that intercepts calls to getObject(), delegating to the current BeanFactory instead of creating a new instance.
private boolean	factoryContainsBean(ConfigurableBeanFactory beanFactory, java.lang.String beanName) Check the BeanFactory to see whether the bean named beanName already exists.
private ConfigurableBeanFactory	getBeanFactory(java.lang.Object enhancedConfigInstance)
java.lang.Object	intercept(java.lang.Object enhancedConfigInstance, java.lang.reflect.Method beanMethod, java.lang.Object[] beanMethodArgs, MethodProxy cglibMethodProxy) Enhance a @Bean method to check the supplied BeanFactory for the existence of this bean object.
private boolean	isCurrentlyInvokedFactoryMethod(java.lang.reflect.Method method) Check whether the given method corresponds to the container's currently invoked factory method.
boolean	isMatch(java.lang.reflect.Method candidateMethod)

Methods inherited from class java.lang.Object

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

Constructor Detail

BeanMethodInterceptor

private BeanMethodInterceptor()

Method Detail

intercept

public java.lang.Object intercept(java.lang.Object enhancedConfigInstance,
                                  java.lang.reflect.Method beanMethod,
                                  java.lang.Object[] beanMethodArgs,
                                  MethodProxy cglibMethodProxy)
                           throws java.lang.Throwable

Enhance a @Bean method to check the supplied BeanFactory for the existence of this bean object.

Throws:

java.lang.Throwable - as a catch-all for any exception that may be thrown when invoking the super implementation of the proxied method i.e., the actual @Bean method

factoryContainsBean

private boolean factoryContainsBean(ConfigurableBeanFactory beanFactory,
                                    java.lang.String beanName)

Check the BeanFactory to see whether the bean named beanName already exists. Accounts for the fact that the requested bean may be "in creation", i.e.: we're in the middle of servicing the initial request for this bean. From an enhanced factory method's perspective, this means that the bean does not actually yet exist, and that it is now our job to create it for the first time by executing the logic in the corresponding factory method.

Said another way, this check repurposes ConfigurableBeanFactory.isCurrentlyInCreation(String) to determine whether the container is calling this method or the user is calling this method.

Parameters:

beanName - name of bean to check for

Returns:

whether beanName already exists in the factory

isCurrentlyInvokedFactoryMethod

private boolean isCurrentlyInvokedFactoryMethod(java.lang.reflect.Method method)

Check whether the given method corresponds to the container's currently invoked factory method. Compares method name and parameter types only in order to work around a potential problem with covariant return types (currently only known to happen on Groovy classes).

enhanceFactoryBean

private java.lang.Object enhanceFactoryBean(java.lang.Object factoryBean,
                                            ConfigurableBeanFactory beanFactory,
                                            java.lang.String beanName)
                                     throws java.lang.InstantiationException,
                                            java.lang.IllegalAccessException

Create a subclass proxy that intercepts calls to getObject(), delegating to the current BeanFactory instead of creating a new instance. These proxies are created only when calling a FactoryBean from within a Bean method, allowing for proper scoping semantics even when working against the FactoryBean instance directly. If a FactoryBean instance is fetched through the container via &-dereferencing, it will not be proxied. This too is aligned with the way XML configuration works.

Throws:

java.lang.InstantiationException

java.lang.IllegalAccessException

getBeanFactory

private ConfigurableBeanFactory getBeanFactory(java.lang.Object enhancedConfigInstance)

isMatch

public boolean isMatch(java.lang.reflect.Method candidateMethod)

Specified by:

isMatch in interface ConfigurationClassEnhancer.ConditionalCallback