Module iu.util.type.impl

Package iu.type

Class TypeTemplate<D,T>

java.lang.Object

iu.type.ElementBase

iu.type.AnnotatedElementBase<Class<T>>

iu.type.DeclaredElementBase<D,Class<T>>

iu.type.TypeTemplate<D,T>

Type Parameters:

D - declaring type

T - raw or generic type

All Implemented Interfaces:

IuAnnotatedElement, IuDeclaredElement<D>, IuNamedElement<D>, IuParameterizedElement, IuType<D,T>, ParameterizedFacade

final class TypeTemplate<D,T>
extends DeclaredElementBase<D,Class<T>>
implements IuType<D,T>, ParameterizedFacade

Represents the internal structure of a TypeFacade.

Each template is a standalone representation of a single generic type, potentially paired with a raw template representing its erasure.

Note that TypeTemplate is not sterotyped as a hash key, but IuType is. This hash key behavior comes from same-instance identity default Object.hashCode() and Object.equals(Object) implementations of instances managed by TypeFactory. Since ClassLoading data is loaded exactly once and remains static once loaded, type introspection instances match that load-once static behavior. It is expected that each raw type (primitive, class, interface, enum, record, etc) has exactly one TypeTemplate instance, and that each TypeTemplate instance backed by a generic type contains a TypeFacade backed by a singleton raw type instances representing its type erasure. This behavior mirrors the hash key behavior of Type, so internal checks for equality (and inequality) may use == (and !=).

Note also that Java does not constrain the number of Type instances, and considers those instances other than Class to be disposable. TypeFactory does not manage TypeTemplate instances for generic type markers once returned to the application.

Initialization Order

Type templates are initialized in two phases, managed by TypeFactory.

1. Declared elements
2. Inherited elements

Declared Elements

Resolved in order upon instantiation:

1. ElementBase(Consumer) preInitHook binds raw Class instances to TypeFactory#RAW_TYPES
2. AnnotatedElementBase(AnnotatedElement, Consumer) binds AnnotatedElementBase.annotatedElement
3. DeclaredElementBase(AnnotatedElement, Consumer, Type, TypeTemplate) binds:
   • DeclaredElementBase.type
   • DeclaredElementBase.declaringType(), potentially null or unsealed
4. Apply actual type arguments from ParameterizedType
5. erase()
6. constructors()

Inherited Elements

Resolved by sealHierarchy(Iterable), order incidental

• fields()
• properties()
• methods()
• typeParameters()

Field Summary

Fields inherited from class iu.type.DeclaredElementBase

declaringType, type

Fields inherited from class iu.type.AnnotatedElementBase

annotatedElement

Constructor Summary

Constructors

Constructor	Description
TypeTemplate(Class<T> rawClass, Consumer<TypeTemplate<?,?>> preInitHook)	Raw class constructor intended for use only by TypeFactory.
TypeTemplate(Consumer<TypeTemplate<?,?>> preInitHook, Type type, TypeTemplate<D,T> erasedType)	Generic type constructor intended for use only by TypeFactory.

Method Summary

Modifier and Type	Method	Description
Iterable<? extends IuConstructor<T>>	constructors()	Gets all constructors defined by this type.
Type	deref()	Gets the generic type.
void	destroy(T instance)	Destroys an instance.
Iterable<TypeFacade<T,?>>	enclosedTypes()	Gets enclosed types.
IuType<D,T>	erase()	Gets the erased facade, which describing the Class representing the erasure of the generic type.
Class<T>	erasedClass()	Get the type erasure class.
<F> FieldFacade<? super T,F>	field(String name)	Gets a field declared by this type.
Iterable<FieldFacade<? super T,?>>	fields()	Gets all fields defined by this type, followed by all fields defined by all types in this type's hierarchy, in IuType.hierarchy() order.
Iterable<TypeFacade<?,? super T>>	hierarchy()	Iterates the type hierarchy, from most specific to least specific.
Iterable<MethodFacade<? super T,?>>	methods()	Gets all methods defined by this type.
String	name()	Gets the name.
void	observe(T instance)	Observes a new instance.
Iterable<PropertyFacade<? super T,?>>	properties()	Gets all properties defined by this type, followed by all properties defined by all types in this type's hierarchy, in IuType.hierarchy() order.
<P> PropertyFacade<? super T,P>	property(String name)	Gets a property declared by this type.
IuTypeReference<T,?>	reference()	Gets the reference used to obtain this type.
IuType<?,? super T>	referTo(Type referentType)	Refers to a type in the the described type's hierarchy.
(package private) final void	seal()	Unsupported, use sealHierarchy(Iterable) to provide hierarchy when sealing.
(package private) void	sealHierarchy(Iterable<? extends IuType<?,? super T>> hierarchy)	Seals hierarchy() and resolves inherited elements.
Runnable	subscribe(InstanceReference<T> instanceReference)	Subscribes a new instance reference.
String	toString()
Map<String,TypeFacade<?,?>>	typeParameters()	Gets type parameters by name.

Methods inherited from class iu.type.DeclaredElementBase

declaringType

Methods inherited from class iu.type.AnnotatedElementBase

annotation, annotations, hasAnnotation, permitted

Methods inherited from class iu.type.ElementBase

checkSealed, postInit

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface edu.iu.type.IuAnnotatedElement

annotation, annotations, hasAnnotation, permitted, permitted

Methods inherited from interface edu.iu.type.IuDeclaredElement

declaringType

Methods inherited from interface edu.iu.type.IuType

annotatedConstructors, annotatedFields, annotatedMethods, annotatedProperties, autoboxClass, autoboxDefault, constructor, constructor, method, method, sub

Methods inherited from interface iu.type.ParameterizedFacade

typeParameter

Constructor Details

TypeTemplate

TypeTemplate(Class<T> rawClass,
 Consumer<TypeTemplate<?,?>> preInitHook)

Raw class constructor intended for use only by TypeFactory.

Parameters:

rawClass - raw class

preInitHook - receives a handle to this after binding the annotated element but before initializing and members

TypeTemplate

TypeTemplate(Consumer<TypeTemplate<?,?>> preInitHook,
 Type type,
 TypeTemplate<D,T> erasedType)

Generic type constructor intended for use only by TypeFactory.

Parameters:

preInitHook - receives a handle to this after binding the annotated element but before initializing and members

type - generic type; must not be a class

erasedType - pre-calculated raw type template; a TypeTemplate cannot be created for a generic type without a fully-formed instance of its type erasure, provided as an argument to this parameter

Method Details

seal

final void seal()
         throws UnsupportedOperationException

Unsupported, use sealHierarchy(Iterable) to provide hierarchy when sealing.

Overrides:

seal in class ElementBase

Throws:

UnsupportedOperationException - when invoked

sealHierarchy

void sealHierarchy(Iterable<? extends IuType<?,? super T>> hierarchy)

Seals hierarchy() and resolves inherited elements.

Parameters:

hierarchy - Resolved type hierarchy

subscribe

public Runnable subscribe(InstanceReference<T> instanceReference)

Description copied from interface: IuType

Subscribes a new instance reference.

Specified by:

subscribe in interface IuType<D,T>

Parameters:

instanceReference - will accept all observed instances until unsubscribed.

Returns:

thunk for unsubscribing the reference

observe

public void observe(T instance)

Description copied from interface: IuType

Observes a new instance.

Observing an instance registers it with the implementation module as an available target for type introspection, for example, for resource binding. Implementors of InstanceReference may use IuType.subscribe(InstanceReference) to be notified when new instances are observed.

Once all InstanceReferences have been notified, all methods annotated by @PostConstruct will be invoked on the instance.

Observing an instance that is already observed has no effect, nor does observing an instance of a type that has no subscribers. All instances provided via IuExecutable.exec(Object...) are observed automatically. This method is a no-op for those instances, however it is up to implementors to ensure @PostConstruct methods do not result in errors or repeat initialization steps when invoked repeatedly.

Specified by:

observe in interface IuType<D,T>

Parameters:

instance - to observe

destroy

public void destroy(T instance)

Description copied from interface: IuType

Destroys an instance.

Invokes all @PreDestroy methods on an instance. If the instance was observed, its state will be reverted and no futures actions will be taken on it.

This method may be invoked to close the lifecycle of instances created via IuExecutable.exec(Object...).

Destroying an instance that is already destroyed should have no effect, but it is up to implementors to ensure @PreDestroy methods do not result in errors or other side-effects when invoked repeatedly.

Specified by:

destroy in interface IuType<D,T>

Parameters:

instance - to destroy

typeParameters

public Map<String,TypeFacade<?,?>> typeParameters()

Description copied from interface: IuParameterizedElement

Gets type parameters by name.

Specified by:

typeParameters in interface IuParameterizedElement

Specified by:

typeParameters in interface ParameterizedFacade

Returns:

map of type parameter facades

name

public String name()

Description copied from interface: IuNamedElement

Gets the name.

Specified by:

name in interface IuNamedElement<D>

Returns:

name

reference

public IuTypeReference<T,?> reference()

Description copied from interface: IuType

Gets the reference used to obtain this type.

Specified by:

reference in interface IuType<D,T>

Returns:

type reference

deref

public Type deref()

Description copied from interface: IuType

Gets the generic type.

Specified by:

deref in interface IuType<D,T>

Returns:

generic type

erase

public IuType<D,T> erase()

Description copied from interface: IuType

Gets the erased facade, which describing the Class representing the erasure of the generic type.

The IuType.deref() of the erased facade must return a Class.

Specified by:

erase in interface IuType<D,T>

Returns:

erased type facade

See Also:

• JLS 21 Section 4.4: Type Erasure

erasedClass

public Class<T> erasedClass()

Description copied from interface: IuType

Get the type erasure class.

Shorthand for IuType.erase().IuType.deref()

Specified by:

erasedClass in interface IuType<D,T>

Returns:

type erasure class

See Also:

• IuType.erase()
• JLS 21 Section 4.4: Type Erasure

referTo

public IuType<?,? super T> referTo(Type referentType)

Description copied from interface: IuType

Refers to a type in the the described type's hierarchy.

When the referent type declares type parameters, the resolved generic types associated with those parameters are described by the returned facade.

Specified by:

referTo in interface IuType<D,T>

Parameters:

referentType - type to refer to

Returns:

referent facade

enclosedTypes

public Iterable<TypeFacade<T,?>> enclosedTypes()

Description copied from interface: IuType

Gets enclosed types.

Specified by:

enclosedTypes in interface IuType<D,T>

Returns:

enclosed types

constructors

public Iterable<? extends IuConstructor<T>> constructors()

Description copied from interface: IuType

Gets all constructors defined by this type.

Specified by:

constructors in interface IuType<D,T>

Returns:

constructors

hierarchy

public Iterable<TypeFacade<?,? super T>> hierarchy()

Description copied from interface: IuType

Iterates the type hierarchy, from most specific to least specific.

1. All Class.getGenericInterfaces()
2. Class.getGenericSuperclass()
3. Iterate IuType.hierarchy() until Object is reached

This type described by this facade is not included. Object is always the last element.

Specified by:

hierarchy in interface IuType<D,T>

Returns:

inherited and extended types

field

public <F> FieldFacade<? super T,F> field(String name)

Description copied from interface: IuType

Gets a field declared by this type.

When a private field has the same name as a different field declared by a super class, the "inherited" field is shadowed by this method. To retrieve all fields, including those shadowed by a superclass, use IuType.fields().

Specified by:

field in interface IuType<D,T>

Type Parameters:

F - field type

Parameters:

name - field name

Returns:

field

fields

public Iterable<FieldFacade<? super T,?>> fields()

Description copied from interface: IuType

Gets all fields defined by this type, followed by all fields defined by all types in this type's hierarchy, in IuType.hierarchy() order.

Specified by:

fields in interface IuType<D,T>

Returns:

fields declared by this type and its hierarchy, in this followed by IuType.hierarchy() order

property

public <P> PropertyFacade<? super T,P> property(String name)

Description copied from interface: IuType

Gets a property declared by this type.

Specified by:

property in interface IuType<D,T>

Type Parameters:

P - property type

Parameters:

name - property name

Returns:

property

properties

public Iterable<PropertyFacade<? super T,?>> properties()

Description copied from interface: IuType

Gets all properties defined by this type, followed by all properties defined by all types in this type's hierarchy, in IuType.hierarchy() order.

Specified by:

properties in interface IuType<D,T>

Returns:

properties declared by this type and its hierarchy, in this followed by IuType.hierarchy() order

methods

public Iterable<MethodFacade<? super T,?>> methods()

Description copied from interface: IuType

Gets all methods defined by this type.

The result iterates all methods declared on all classes in the type erasure's hierarchy with private erasure for duplicately defined methods.

Specified by:

methods in interface IuType<D,T>

Returns:

methods

toString

public String toString()

Overrides:

toString in class Object