public class PropertiesFactoryBean extends PropertiesLoaderSupport implements FactoryBean<Properties>, InitializingBean
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.
|Constructor and Description|
|Modifier and Type||Method and Description|
Invoked by the containing
Template method that subclasses may override to construct the object returned by this factory.
Return an instance (possibly shared or independent) of the object managed by this factory.
Return the type of object that this FactoryBean creates, or
Is the object managed by this factory a singleton? That is, will
Set whether a shared 'singleton' Properties instance should be created, or rather a new Properties instance on each request.
loadProperties, mergeProperties, setFileEncoding, setIgnoreResourceNotFound, setLocalOverride, setLocation, setLocations, setProperties, setPropertiesArray, setPropertiesPersister
public final void setSingleton(boolean singleton)
Default is "true" (a shared singleton).
public final boolean isSingleton()
FactoryBean.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 return
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 extended
may explicitly indicate independent instances through its
SmartFactoryBean.isPrototype() method. Plain
implementations which do not implement this extended interface are
simply assumed to always return independent instances if the
isSingleton() implementation returns
The default implementation returns
true, since a
FactoryBean typically manages a singleton instance.
public final void afterPropertiesSet() throws IOException
BeanFactoryafter it has set all bean properties and satisfied
This method allows the bean instance to perform validation of its overall configuration and final initialization when all bean properties have been set.
@Nullable public final Properties getObject() throws IOException
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
As of Spring 2.0, FactoryBeans are allowed to return
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.
public Class<Properties> getObjectType()
nullif 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.
nullif not known at the time of the call
protected Properties createProperties() throws IOException
Invoked on initialization of this FactoryBean in case of a
shared singleton; else, on each