The BasicFactoryDefinitionParser supports two kinds of
factory definitions:
- some.package.SomeFactory#createObject
This defines that the 'createObject' of the class 'some.package.SomeFactory'
should be called for creating the target object.
- some.package.SomeFactorySingleton#getFactoryMethod.createObject
This defines that the 'getFactoryMethod' of the class 'some.package.SomeFactorySingleton'
should be called to retrieve the factory object on which the 'createObject' should
be called for creating the target object.
The factory retrieval method should never return null. This
will result in a NullPointerException.