org.onebusaway.container.spring
Class DependencyConfigurer

java.lang.Object
  extended by org.springframework.core.io.support.PropertiesLoaderSupport
      extended by org.springframework.beans.factory.config.PropertyResourceConfigurer
          extended by org.onebusaway.container.spring.DependencyConfigurer
All Implemented Interfaces:
org.springframework.beans.factory.config.BeanFactoryPostProcessor, org.springframework.core.Ordered, org.springframework.core.PriorityOrdered

public class DependencyConfigurer
extends org.springframework.beans.factory.config.PropertyResourceConfigurer

A Spring BeanFactoryPostProcessor that can set bean dependencies to adjust bean creation order. Typically, you don't need to set bean dependencies directly, as Spring figures it out from bean references in your application context in bean property setters. Sometimes, you need to set a dependency that Spring cannot detect on its own, and you'd do this by adjusting the depends-on attribute of a bean defintion. While that works for most cases, we've managed to find a case where that doesn't work. To give a specific example, we're creating a Hibernate SessionFactory that uses an EhCache CacheManager to manage the second-level cache, as defined in the org/onebusaway/container/application-context-caching.xml and org/onebusaway/container/application-context-hibernate.xml application context config files. A number of modules import these configs and add additional Hibernate entity classes and mappings. These modules would also like to add EhCache second-level caches for these entity classes. These caches can be created with EhCacheFactoryBean, but they need to be instantiated before the SessionFactory, as the session factory will query the CacheManager for cache entries on creation. To ensure that these cache factories are instantiated before the session factory, and we can't set the depends-on for the session factory in the config, we use the DependencyConfigurer to manipulate the dependency relationship directly. To use DependencyConfigurer, set a "properties" property for the bean definition where the each property key is a bean name and each property value is a list of dependent bean names separated by commas. So for example:

 
   
     
     beanB,beanC
    
   
 
 
This would make the bean "beanA" depend on beans "beanB" and "beanC".

Author:
bdferris

Field Summary
 
Fields inherited from class org.springframework.core.io.support.PropertiesLoaderSupport
logger, XML_FILE_EXTENSION
 
Fields inherited from interface org.springframework.core.Ordered
HIGHEST_PRECEDENCE, LOWEST_PRECEDENCE
 
Constructor Summary
DependencyConfigurer()
           
 
Method Summary
protected  void processKey(org.springframework.beans.factory.config.ConfigurableListableBeanFactory beanFactory, String beanName, String property)
           
protected  void processProperties(org.springframework.beans.factory.config.ConfigurableListableBeanFactory beanFactory, Properties props)
           
 
Methods inherited from class org.springframework.beans.factory.config.PropertyResourceConfigurer
convertProperties, convertPropertyValue, getOrder, postProcessBeanFactory, setOrder
 
Methods inherited from class org.springframework.core.io.support.PropertiesLoaderSupport
loadProperties, mergeProperties, setFileEncoding, setIgnoreResourceNotFound, setLocalOverride, setLocation, setLocations, setProperties, setPropertiesArray, setPropertiesPersister
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

DependencyConfigurer

public DependencyConfigurer()
Method Detail

processProperties

protected void processProperties(org.springframework.beans.factory.config.ConfigurableListableBeanFactory beanFactory,
                                 Properties props)
                          throws org.springframework.beans.BeansException
Specified by:
processProperties in class org.springframework.beans.factory.config.PropertyResourceConfigurer
Throws:
org.springframework.beans.BeansException

processKey

protected void processKey(org.springframework.beans.factory.config.ConfigurableListableBeanFactory beanFactory,
                          String beanName,
                          String property)


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