Workaround ResolvableType.forClassWithGenerics bug

Temporarily work around SPR-16456

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/properties/bind/CollectionBinder.java

@@ -40,7 +40,7 @@ class CollectionBinder extends IndexedElementsBinder<Collection<Object>> {
 			AggregateElementBinder elementBinder) {
 		Class<?> collectionType = (target.getValue() == null ? target.getType().resolve()
 				: List.class);
-		ResolvableType aggregateType = ResolvableType.forClassWithGenerics(List.class,
+		ResolvableType aggregateType = forClassWithGenerics(List.class,
 				target.getType().asCollection().getGenerics());
 		ResolvableType elementType = target.getType().asCollection().getGeneric();
 		IndexedCollectionSupplier result = new IndexedCollectionSupplier(

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/context/properties/bind/IndexedElementsBinder.java

@@ -79,8 +79,8 @@ abstract class IndexedElementsBinder<T> extends AggregateBinder<T> {
 		ConfigurationProperty property = source.getConfigurationProperty(root);
 		if (property != null) {
 			Object aggregate = convert(property.getValue(), aggregateType);
-			ResolvableType collectionType = ResolvableType
+			ResolvableType collectionType = forClassWithGenerics(
-					.forClassWithGenerics(collection.get().getClass(), elementType);
+					collection.get().getClass(), elementType);
 			Collection<Object> elements = convert(aggregate, collectionType);
 			collection.get().addAll(elements);
 		}
@@ -140,6 +140,17 @@ abstract class IndexedElementsBinder<T> extends AggregateBinder<T> {
 		return ResolvableTypeDescriptor.forType(type).convert(conversionService, value);
 	}
 
+	// Work around for SPR-16456
+	protected static ResolvableType forClassWithGenerics(Class<?> type,
+			ResolvableType... generics) {
+		ResolvableType[] resolvedGenerics = new ResolvableType[generics.length];
+		for (int i = 0; i < generics.length; i++) {
+			resolvedGenerics[i] = forClassWithGenerics(generics[i].resolve(),
+					generics[i].getGenerics());
+		}
+		return ResolvableType.forClassWithGenerics(type, resolvedGenerics);
+	}
+
 	/**
 	 * {@link AggregateBinder.AggregateSupplier AggregateSupplier} for an indexed
 	 * collection.