Class PropertiesFactoryBean
- java.lang.Object
- org.springframework.core.io.support.PropertiesLoaderSupport
- org.springframework.beans.factory.config.PropertiesFactoryBean
- All Implemented Interfaces:
FactoryBean<Properties>
,InitializingBean
public class PropertiesFactoryBean extends PropertiesLoaderSupport implements FactoryBean<Properties>, InitializingBean
Allows for making a properties file from a classpath location available as Properties instance in a bean factory. Can be used 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 a singleton.
Field Summary
Fields inherited from class org.springframework.core.io.support.PropertiesLoaderSupport
localOverride, localProperties, logger
Fields inherited from interface org.springframework.beans.factory.FactoryBean
OBJECT_TYPE_ATTRIBUTE
Constructor Summary
Constructors Constructor Description PropertiesFactoryBean()
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description void
afterPropertiesSet()
Invoked by the containingBeanFactory
after it has set all bean properties and satisfiedBeanFactoryAware
,ApplicationContextAware
etc.protected Properties
createProperties()
Template method that subclasses may override to construct the object returned by this factory.Properties
getObject()
Return an instance (possibly shared or independent) of the object managed by this factory.Class<Properties>
getObjectType()
Return the type of object that this FactoryBean creates, ornull
if not known in advance.boolean
isSingleton()
Is the object managed by this factory a singleton? That is, willFactoryBean.getObject()
always return the same object (a reference that can be cached)?void
setSingleton(boolean singleton)
Set whether a shared 'singleton' Properties instance should be created, or rather a new Properties instance on each request.Methods inherited from class org.springframework.core.io.support.PropertiesLoaderSupport
loadProperties, mergeProperties, setFileEncoding, setIgnoreResourceNotFound, setLocalOverride, setLocation, setLocations, setProperties, setPropertiesArray, setPropertiesPersister
Constructor Detail
PropertiesFactoryBean
public PropertiesFactoryBean()
Method Detail
setSingleton
public final void setSingleton(boolean singleton)
Set whether a shared 'singleton' Properties instance should be created, or rather a new Properties instance on each request.Default is "true" (a shared singleton).
isSingleton
public final boolean isSingleton()
Description copied from interface:FactoryBean
Is the object managed by this factory a singleton? That is, willFactoryBean.getObject()
always return the same object (a reference that can be cached)?NOTE: If a FactoryBean indicates to hold a singleton object, the object returned from
getObject()
might get cached by the owning BeanFactory. Hence, do not returntrue
unless the FactoryBean always exposes the same reference.The singleton status of the FactoryBean itself will generally be provided by the owning BeanFactory; usually, it has to be defined as singleton there.
NOTE: This method returning
false
does not necessarily indicate that returned objects are independent instances. An implementation of the extendedSmartFactoryBean
interface may explicitly indicate independent instances through itsSmartFactoryBean.isPrototype()
method. PlainFactoryBean
implementations which do not implement this extended interface are simply assumed to always return independent instances if theisSingleton()
implementation returnsfalse
.The default implementation returns
true
, since aFactoryBean
typically manages a singleton instance.- Specified by:
isSingleton
in interfaceFactoryBean<Properties>
- Returns:
- whether the exposed object is a singleton
- See Also:
FactoryBean.getObject()
,SmartFactoryBean.isPrototype()
afterPropertiesSet
public final void afterPropertiesSet() throws IOException
Description copied from interface:InitializingBean
Invoked by the containingBeanFactory
after it has set all bean properties and satisfiedBeanFactoryAware
,ApplicationContextAware
etc.This method allows the bean instance to perform validation of its overall configuration and final initialization when all bean properties have been set.
- Specified by:
afterPropertiesSet
in interfaceInitializingBean
- Throws:
IOException
getObject
@Nullable public final Properties 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 FactoryBean is not fully initialized yet at the time of the call (for example because it is involved in a circular reference), throw a corresponding
FactoryBeanNotInitializedException
.As of Spring 2.0, FactoryBeans are allowed to return
null
objects. The factory will consider this as normal value to be used; it will not throw a FactoryBeanNotInitializedException in this case anymore. FactoryBean implementations are encouraged to throw FactoryBeanNotInitializedException themselves now, as appropriate.- Specified by:
getObject
in interfaceFactoryBean<Properties>
- Returns:
- an instance of the bean (can be
null
) - Throws:
IOException
- See Also:
FactoryBeanNotInitializedException
getObjectType
public Class<Properties> getObjectType()
Description copied from interface:FactoryBean
Return the type of object that this FactoryBean creates, ornull
if not known in advance.This allows one to check for specific types of beans without instantiating objects, for example on autowiring.
In the case of implementations that are creating a singleton object, this method 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 interfaceFactoryBean<Properties>
- 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<T>)
createProperties
protected Properties createProperties() throws IOException
Template method that subclasses may override to construct the object returned by this factory. The default implementation returns the plain merged Properties instance.Invoked on initialization of this FactoryBean in case of a shared singleton; else, on each
getObject()
call.- Returns:
- the object returned by this factory
- Throws:
IOException
- if an exception occurred during properties loading- See Also:
PropertiesLoaderSupport.mergeProperties()