ch.jalu.injector.handlers.dependency

Class TypeSafeAnnotationHandler<T extends Annotation>

java.lang.Object

ch.jalu.injector.handlers.dependency.TypeSafeAnnotationHandler<T>

All Implemented Interfaces:

Handler

public abstract class TypeSafeAnnotationHandler<T extends Annotation>
extends Object
implements Handler

Type safe annotation handler base, which will fire the resolve method only if an annotation of the given type is present.

Constructor Summary

Constructors

Constructor and Description
TypeSafeAnnotationHandler()

Method Summary

Modifier and Type	Method and Description
protected abstract Class<T>	getAnnotationType() Returns the class of the annotation the handler can process.
Resolution<?>	resolve(ResolutionContext context) Resolves the context such that the object identified by the context's object identifier can be instantiated or retrieved.
protected abstract Resolution<?>	resolveValueSafely(ResolutionContext context, T annotation) Resolves the value with the matched annotation, guaranteed to never be null.

Methods inherited from class java.lang.Object

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

Methods inherited from interface ch.jalu.injector.handlers.Handler

onAnnotation, onProvider, onProviderClass, postProcess

Constructor Detail

TypeSafeAnnotationHandler

public TypeSafeAnnotationHandler()

Method Detail

resolve

public final Resolution<?> resolve(ResolutionContext context)
                            throws Exception

Description copied from interface: Handler

Resolves the context such that the object identified by the context's object identifier can be instantiated or retrieved. May throw an exception if something is invalid, such as when the requested object is not possible to resolve (e.g. wrong combination of annotations, unmet conditions).

The returned Resolution must correspond to the type represented by the context's object identifier.

Specified by:

resolve in interface Handler

Parameters:

context - the resolution context

Returns:

the instantiation for the class, or null if not possible

Throws:

Exception - for validation errors

getAnnotationType

protected abstract Class<T> getAnnotationType()

Returns the class of the annotation the handler can process.

Returns:

the annotation type

resolveValueSafely

@Nullable
protected abstract Resolution<?> resolveValueSafely(ResolutionContext context,
                                                              T annotation)
                                                       throws Exception

Resolves the value with the matched annotation, guaranteed to never be null.

Parameters:

context - the instantiation context

annotation - the matched annotation

Returns:

the resolved value, or null if none applicable

Throws:

Exception - for invalid usage of annotation