@NotNull
public Instantiator<?> findInstantiator(@NotNull Type type, @NotNull NamedTypeList types) {
// First check if we have an immediate conversion registered. If so, we'll just use that.
if (types.size() == 1) {
TypeConversion conversion = findConversionFromDbValue(types.getType(0), type).orElse(null);
if (conversion != null) return args -> conversion.convert(args.getSingleValue());
}
Class<?> cl = rawType(type);
Instantiator<?> instantiator = findExplicitInstantiatorFor(cl, types).orElse(null);
if (instantiator != null) return instantiator;
if (!isPublic(cl.getModifiers()))
throw new InstantiationFailureException(
type
+ " can't be instantiated reflectively because it is not public or missing a @DalesbredConstructor-annotation");
return candidateConstructorsSortedByDescendingParameterCount(cl)
.map(ctor -> implicitInstantiatorFrom(ctor, types).orElse(null))
.filter(Objects::nonNull)
.findFirst()
.orElseThrow(
() ->
new InstantiationFailureException(
"could not find a way to instantiate " + type + " with parameters " + types));
}
/**
* Returns the list of conversions that need to be performed to convert sourceTypes to
* targetTypes, or empty if conversions can't be done.
*/
@NotNull
private Optional<List<TypeConversion>> resolveConversions(
@NotNull NamedTypeList sourceTypes, @NotNull List<Type> targetTypes) {
if (targetTypes.size() != sourceTypes.size()) return Optional.empty();
ArrayList<TypeConversion> conversions = new ArrayList<>(targetTypes.size());
for (int i = 0, len = targetTypes.size(); i < len; i++) {
TypeConversion conversion =
findConversionFromDbValue(sourceTypes.getType(i), targetTypes.get(i)).orElse(null);
if (conversion != null) conversions.add(conversion);
else return Optional.empty();
}
return Optional.of(conversions);
}
