Spring/spring-framework
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Fix @Autowired+@PostConstruct+@Configuration issue

Browse Source 
A subtle issue existed with the way we relied on isCurrentlyInCreation
to determine whether a @Bean method is being called by the container
or by user code.  This worked in most cases, but in the particular
scenario laid out by SPR-8080, this approach was no longer sufficient.

This change introduces a ThreadLocal that contains the factory method
currently being invoked by the container, such that enhanced @Bean
methods can check against it to see if they are being called by the
container or not.  If so, that is the cue that the user-defined @Bean
method implementation should be invoked in order to actually create
the bean for the first time.  If not, then the cached instance of
the already-created bean should be looked up and returned.

See ConfigurationClassPostConstructAndAutowiringTests for
reproduction cases and more detail.

Issue: SPR-8080
This commit is contained in:
Chris Beams
2011-05-12 12:28:13 +00:00
parent 57206db152
commit 2afeb08e3c
5 changed files with 195 additions and 21 deletions
Download Patch File Download Diff File Expand all files Collapse all files

54
org.springframework.context/src/main/java/org/springframework/context/annotation/ConfigurationClassEnhancer.java
View File

@@ -35,6 +35,7 @@ import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.config.BeanFactoryPostProcessor;
import org.springframework.beans.factory.config.ConfigurableBeanFactory;
import org.springframework.beans.factory.support.SimpleInstantiationStrategy;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.util.Assert;
@@ -233,23 +234,42 @@ class ConfigurationClassEnhancer {
return enhanceFactoryBean(factoryBean.getClass(), beanName);
}
}
// the bean is not a FactoryBean - check to see if it has been cached
if (factoryContainsBean(beanName)) {
// we have an already existing cached instance of this bean -> retrieve it
return this.beanFactory.getBean(beanName);
boolean factoryIsCaller = beanMethod.equals(SimpleInstantiationStrategy.getCurrentlyInvokedFactoryMethod());
boolean factoryAlreadyContainsSingleton = this.beanFactory.containsSingleton(beanName);
if (factoryIsCaller && !factoryAlreadyContainsSingleton) {
// the factory is calling the bean method in order to instantiate and register the bean
// (i.e. via a getBean() call) -> invoke the super implementation of the method to actually
// create the bean instance.
if (BeanFactoryPostProcessor.class.isAssignableFrom(beanMethod.getReturnType())) {
logger.warn(String.format("@Bean method %s.%s is non-static and returns an object " +
"assignable to Spring's BeanFactoryPostProcessor interface. This will " +
"result in a failure to process annotations such as @Autowired, " +
"@Resource and @PostConstruct within the method's declaring " +
"@Configuration class. Add the 'static' modifier to this method to avoid " +
"these container lifecycle issues; see @Bean Javadoc for complete details",
beanMethod.getDeclaringClass().getSimpleName(), beanMethod.getName()));
}
return cglibMethodProxy.invokeSuper(enhancedConfigInstance, beanMethodArgs);
}
else {
// the user (i.e. not the factory) is requesting this bean through a
// call to the bean method, direct or indirect. The bean may have already been
// marked as 'in creation' in certain autowiring scenarios; if so, temporarily
// set the in-creation status to false in order to avoid an exception.
boolean alreadyInCreation = this.beanFactory.isCurrentlyInCreation(beanName);
try {
if (alreadyInCreation) {
this.beanFactory.setCurrentlyInCreation(beanName, false);
}
return this.beanFactory.getBean(beanName);
} finally {
if (alreadyInCreation) {
this.beanFactory.setCurrentlyInCreation(beanName, true);
}
}
}
if (BeanFactoryPostProcessor.class.isAssignableFrom(beanMethod.getReturnType())) {
logger.warn(String.format("@Bean method %s.%s is non-static and returns an object " +
"assignable to Spring's BeanFactoryPostProcessor interface. This will " +
"result in a failure to process annotations such as @Autowired, " +
"@Resource and @PostConstruct within the method's declaring " +
"@Configuration class. Add the 'static' modifier to this method to avoid" +
"these container lifecycle issues; see @Bean Javadoc for complete details",
beanMethod.getDeclaringClass().getSimpleName(), beanMethod.getName()));
}
return cglibMethodProxy.invokeSuper(enhancedConfigInstance, beanMethodArgs);
}
/**
@@ -266,7 +286,9 @@ class ConfigurationClassEnhancer {
* @return whether <var>beanName</var> already exists in the factory
*/
private boolean factoryContainsBean(String beanName) {
return (this.beanFactory.containsBean(beanName) && !this.beanFactory.isCurrentlyInCreation(beanName));
boolean containsBean = this.beanFactory.containsBean(beanName);
boolean currentlyInCreation = this.beanFactory.isCurrentlyInCreation(beanName);
return (containsBean && !currentlyInCreation);
}
/**