Revised 4.3 signatures for MethodParameter/DependencyDescriptor

Issue: SPR-13440

Author: jhoeller

spring-beans/src/main/java/org/springframework/beans/factory/config/DependencyDescriptor.java

@@ -180,6 +180,7 @@ public Object resolveNotUnique(Class<?> type, Map<String, Object> matchingBeans)
 	 * @param beanName the bean name, as a candidate result for this dependency
 	 * @param beanFactory the associated factory
 	 * @return the bean instance (never {@code null})
+	 * @since 4.3
 	 * @see BeanFactory#getBean(String)
 	 */
 	public Object resolveCandidate(String beanName, BeanFactory beanFactory) {
@@ -278,6 +279,7 @@ public Class<?> getDependencyType() {
 						Type[] args = ((ParameterizedType) type).getActualTypeArguments();
 						type = args[args.length - 1];
 					}
+					// TODO: Object.class if unresolvable
 				}
 				if (type instanceof Class) {
 					return (Class<?>) type;

spring-core/src/main/java/org/springframework/core/MethodParameter.java

@@ -406,6 +406,7 @@ public Class<?> getNestedParameterType() {
 					Integer index = getTypeIndexForLevel(i);
 					type = args[index != null ? index : args.length - 1];
 				}
+				// TODO: Object.class if unresolvable
 			}
 			if (type instanceof Class) {
 				return (Class<?>) type;
@@ -462,6 +463,16 @@ public <A extends Annotation> A getMethodAnnotation(Class<A> annotationType) {
 		return adaptAnnotation(getAnnotatedElement().getAnnotation(annotationType));
 	}
 
+	/**
+	 * Return whether the method/constructor is annotated with the given type.
+	 * @param annotationType the annotation type to look for
+	 * @since 4.3
+	 * @see #getMethodAnnotation(Class)
+	 */
+	public <A extends Annotation> boolean hasMethodAnnotation(Class<A> annotationType) {
+		return getAnnotatedElement().isAnnotationPresent(annotationType);
+	}
+
 	/**
 	 * Return the annotations associated with the specific method/constructor parameter.
 	 */
@@ -479,33 +490,37 @@ public Annotation[] getParameterAnnotations() {
 		return this.parameterAnnotations;
 	}
 
+	/**
+	 * Return {@code true} if the parameter has at least one annotation,
+	 * {@code false} if it has none.
+	 * @see #getParameterAnnotations()
+	 */
+	public boolean hasParameterAnnotations() {
+		return (getParameterAnnotations().length != 0);
+	}
+
 	/**
 	 * Return the parameter annotation of the given type, if available.
 	 * @param annotationType the annotation type to look for
 	 * @return the annotation object, or {@code null} if not found
 	 */
 	@SuppressWarnings("unchecked")
-	public <T extends Annotation> T getParameterAnnotation(Class<T> annotationType) {
+	public <A extends Annotation> A getParameterAnnotation(Class<A> annotationType) {
 		Annotation[] anns = getParameterAnnotations();
 		for (Annotation ann : anns) {
 			if (annotationType.isInstance(ann)) {
-				return (T) ann;
+				return (A) ann;
 			}
 		}
 		return null;
 	}
 
 	/**
-	 * Return true if the parameter has at least one annotation, false if it has none.
-	 */
-	public boolean hasParameterAnnotations() {
-		return (getParameterAnnotations().length != 0);
-	}
-
-	/**
-	 * Return true if the parameter has the given annotation type, and false if it doesn't.
+	 * Return whether the parameter is declared with the given annotation type.
+	 * @param annotationType the annotation type to look for
+	 * @see #getParameterAnnotation(Class)
 	 */
-	public <T extends Annotation> boolean hasParameterAnnotation(Class<T> annotationType) {
+	public <A extends Annotation> boolean hasParameterAnnotation(Class<A> annotationType) {
 		return (getParameterAnnotation(annotationType) != null);
 	}