Module org.refcodes.factory

Package org.refcodes.factory

Interface TypeFactory<T>

Type Parameters:

T - The type of the instances being served by the factory.

All Superinterfaces:

org.refcodes.mixin.TypeAccessor<T>

All Known Implementing Classes:

ClassTypeFactory, PrototypeFactory

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface TypeFactory<T>
extends org.refcodes.mixin.TypeAccessor<T>

The TypeFactory defines the functionality which must be provided in order to represent a factory for object creation of a predefined type specified with a generic argument (in contrast to the BeanLookupFactory , which creates instances of an expected type). Many alternative implementations of a TypeFactory may may exist which construct the instances their way.

Having factories that generic as we define it here, we are able to decouple our business logic from any specific framework: Your business logic must not know anything about how the instances are generated. It mainly just needs to know how to use the TypeFactory. It is up to the application "end point", i.e. a command line tool with a main-method or a web-application to finally decide which factory to use.

Depending on the implementation used or configuration provided, the TypeFactory may return singletons or dedicated separate instances when queried for instances.

Nested Class Summary

Nested classes/interfaces inherited from interface org.refcodes.mixin.TypeAccessor

org.refcodes.mixin.TypeAccessor.TypeBuilder<T extends Object,B extends org.refcodes.mixin.TypeAccessor.TypeBuilder<T,B>>, org.refcodes.mixin.TypeAccessor.TypeMutator<T extends Object>, org.refcodes.mixin.TypeAccessor.TypeProperty<T extends Object>

Method Summary

Modifier and Type	Method	Description
T	createInstance()	This method creates / retrieves an instance of the given type with the given identifier (name) constructed as defined in one to many configuration files.
default T	createInstance(Map<String,String> aProperties)	This method creates / retrieves an instance of the given type with the given identifier (name) constructed as defined in one to many configuration files.
default Class<T>	getType()	This method retrieves the type which the implementing factory produces.

Method Detail

createInstance

T createInstance()

This method creates / retrieves an instance of the given type with the given identifier (name) constructed as defined in one to many configuration files. How the instance is configured, created or retrieved is up to the nature (implementation) of the according factory.

Returns:

The instance being fabricated by this factory.

Throws:

ClassCastException - in case the fabricated type is not type compatible with the required type T.

createInstance

default T createInstance(Map<String,String> aProperties)

This method creates / retrieves an instance of the given type with the given identifier (name) constructed as defined in one to many configuration files. How the instance is configured, created or retrieved is up to the nature (implementation) of the according factory.

Parameters:

aProperties - The dynamic properties which are used to configure the desired bean.

Returns:

The instance being fabricated by this factory.

Throws:

ClassCastException - in case the fabricated type is not type compatible with the required type T.

getType

default Class<T> getType()

This method retrieves the type which the implementing factory produces. In favor to clean instance creation, shortcomings of java's type system are compensated by calling createInstance()'s Object.getClass() (as we cannot get a generic type's class if not explicitly passed to an instance e.g. through it's constructor). Attention: To avoid unnecessary calls to potentially expensive createInstance() methods, please overwrite this method.

Specified by:

getType in interface org.refcodes.mixin.TypeAccessor<T>

Returns:

The type of the instances this factory produces.