org.springframework.beans.factory.config
Class PropertiesFactoryBean

java.lang.Object
  extended by org.springframework.core.io.support.PropertiesLoaderSupport
      extended by org.springframework.beans.factory.config.PropertiesFactoryBean
All Implemented Interfaces:
FactoryBean, InitializingBean
Direct Known Subclasses:
ResourceMapFactoryBean

public class PropertiesFactoryBean
extends PropertiesLoaderSupport
implements FactoryBean, InitializingBean

Allows for making a properties file from a classpath location available as Properties instance in a bean factory. Can be used for to populate any bean property of type Properties via a bean reference.

Supports loading from a properties file and/or setting local properties on this FactoryBean. The created Properties instance will be merged from loaded and local values. If neither a location nor local properties are set, an exception will be thrown on initialization.

Can create a singleton or a new object on each request. Default is singleton.

Author:
Juergen Hoeller
See Also:
Properties

Field Summary
 
Fields inherited from class org.springframework.core.io.support.PropertiesLoaderSupport
logger, XML_FILE_EXTENSION
 
Constructor Summary
PropertiesFactoryBean()
           
 
Method Summary
 void afterPropertiesSet()
          Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).
protected  Object createInstance()
          Template method that subclasses may override to construct the object returned by this factory.
 Object getObject()
          Return an instance (possibly shared or independent) of the object managed by this factory.
 Class getObjectType()
          Return the type of object that this FactoryBean creates, or null if not known in advance.
 boolean isSingleton()
          Is the bean managed by this factory a singleton or a prototype?
 void setSingleton(boolean singleton)
          Set if a singleton should be created, or a new object on each request else.
 
Methods inherited from class org.springframework.core.io.support.PropertiesLoaderSupport
loadProperties, mergeProperties, setFileEncoding, setIgnoreResourceNotFound, setLocalOverride, setLocation, setLocations, setProperties, setPropertiesPersister
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

PropertiesFactoryBean

public PropertiesFactoryBean()
Method Detail

setSingleton

public final void setSingleton(boolean singleton)
Set if a singleton should be created, or a new object on each request else. Default is true (a singleton).


isSingleton

public final boolean isSingleton()
Description copied from interface: FactoryBean
Is the bean managed by this factory a singleton or a prototype? That is, will getObject() always return the same object?

The singleton status of the FactoryBean itself will generally be provided by the owning BeanFactory; usually, it has to be defined as singleton there.

Specified by:
isSingleton in interface FactoryBean
Returns:
if this bean is a singleton

afterPropertiesSet

public final void afterPropertiesSet()
                              throws IOException
Description copied from interface: InitializingBean
Invoked by a BeanFactory after it has set all bean properties supplied (and satisfied BeanFactoryAware and ApplicationContextAware).

This method allows the bean instance to perform initialization only possible when all bean properties have been set and to throw an exception in the event of misconfiguration.

Specified by:
afterPropertiesSet in interface InitializingBean
Throws:
IOException

getObject

public final Object getObject()
                       throws IOException
Description copied from interface: FactoryBean
Return an instance (possibly shared or independent) of the object managed by this factory. As with a BeanFactory, this allows support for both the Singleton and Prototype design pattern.

If this method returns null, the factory will consider the FactoryBean as not fully initialized and throw a corresponding FactoryBeanNotInitializedException.

Specified by:
getObject in interface FactoryBean
Returns:
an instance of the bean (should not be null; a null value will be considered as an indication of incomplete initialization)
Throws:
IOException
See Also:
FactoryBeanNotInitializedException

getObjectType

public Class getObjectType()
Description copied from interface: FactoryBean
Return the type of object that this FactoryBean creates, or null if not known in advance. This allows to check for specific types of beans without instantiating objects, for example on autowiring.

For a singleton, this should try to avoid singleton creation as far as possible; it should rather estimate the type in advance. For prototypes, returning a meaningful type here is advisable too.

This method can be called before this FactoryBean has been fully initialized. It must not rely on state created during initialization; of course, it can still use such state if available.

NOTE: Autowiring will simply ignore FactoryBeans that return null here. Therefore it is highly recommended to implement this method properly, using the current state of the FactoryBean.

Specified by:
getObjectType in interface FactoryBean
Returns:
the type of object that this FactoryBean creates, or null if not known at the time of the call
See Also:
ListableBeanFactory.getBeansOfType(java.lang.Class)

createInstance

protected Object createInstance()
                         throws IOException
Template method that subclasses may override to construct the object returned by this factory. Default returns the plain merged Properties.

Invoked on initialization of this FactoryBean in case of a singleton; else, on each getObject() call.

Returns:
the object returned by this factory
Throws:
IOException - if an exception occured during properties loading
See Also:
getObject(), PropertiesLoaderSupport.mergeProperties()


Copyright (c) 2002-2005 The Spring Framework Project.