A factory providing convenient access to a FormattingConversionService
configured with converters and formatters for common types such as numbers and
datetimes.
Additional converters and formatters can be registered declaratively through
setConverters(Set) and setFormatters(Set). Another option
is to register converters and formatters in code by implementing the
FormatterRegistrar interface. You can then configure provide the set
of registrars to use through setFormatterRegistrars(Set).
A good example for registering converters and formatters in code is
JodaTimeFormatterRegistrar, which registers a number of
date-related formatters and converters. For a more detailed list of cases
see setFormatterRegistrars(Set)
Like all FactoryBean implementations, this class is suitable for
use when configuring a Spring application context using Spring <beans>
XML. When configuring the container with
@Configuration
classes, simply instantiate, configure and return the appropriate
FormattingConversionService object from a
@Bean method.
Since:
3.0
Author:
Keith Donald, Juergen Hoeller, Rossen Stoyanchev, Chris Beams
Is the object managed by this factory a singleton? That is,
will FactoryBean.getObject() always return the same object
(a reference that can be cached)?
Configure the set of FormatterRegistrars to invoke to register
Converters and Formatters in addition to those added declaratively
via setConverters(Set) and setFormatters(Set).
public void setFormatterRegistrars(java.util.Set<FormatterRegistrar> formatterRegistrars)
Configure the set of FormatterRegistrars to invoke to register
Converters and Formatters in addition to those added declaratively
via setConverters(Set) and setFormatters(Set).
FormatterRegistrars are useful when registering multiple related
converters and formatters for a formatting category, such as Date
formatting. All types related needed to support the formatting
category can be registered from one place.
FormatterRegistrars can also be used to register Formatters
indexed under a specific field type different from its own <T>,
or when registering a Formatter from a Printer/Parser pair.
Invoked by the containing BeanFactory after it has set all bean properties
and satisfied BeanFactoryAware, 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.
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.
Return the type of object that this FactoryBean creates,
or null 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.
Is the object managed by this factory a singleton? That is,
will 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 true
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 SmartFactoryBean interface
may explicitly indicate independent instances through its
SmartFactoryBean.isPrototype() method. Plain FactoryBean
implementations which do not implement this extended interface are
simply assumed to always return independent instances if the
isSingleton() implementation returns false.
The default implementation returns true, since a
FactoryBean typically manages a singleton instance.