Move BindingReflectionHintsRegistrar to spring-context

Closes gh-28735

spring-context/src/main/java/org/springframework/context/aot/BindingReflectionHintsRegistrar.java

@@ -0,0 +1,175 @@
+/*
+ * Copyright 2002-2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.context.aot;
+
+import java.beans.BeanInfo;
+import java.beans.IntrospectionException;
+import java.beans.Introspector;
+import java.beans.PropertyDescriptor;
+import java.lang.reflect.Method;
+import java.lang.reflect.RecordComponent;
+import java.lang.reflect.Type;
+import java.util.LinkedHashSet;
+import java.util.Set;
+import java.util.function.Consumer;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+import org.springframework.aot.hint.ExecutableHint;
+import org.springframework.aot.hint.ExecutableMode;
+import org.springframework.aot.hint.MemberCategory;
+import org.springframework.aot.hint.ReflectionHints;
+import org.springframework.core.KotlinDetector;
+import org.springframework.core.MethodParameter;
+import org.springframework.core.ResolvableType;
+import org.springframework.lang.Nullable;
+import org.springframework.util.ClassUtils;
+
+/**
+ * Register the necessary reflection hints so that the specified type can be
+ * bound at runtime. Fields, constructors and property methods are registered,
+ * except for a set of types like those in the {@code java.} package where just
+ * the type is registered. Types are discovered transitively and generic types
+ * are registered as well.
+ *
+ * @author Sebastien Deleuze
+ * @since 6.0
+ */
+public class BindingReflectionHintsRegistrar {
+
+	private static final Log logger = LogFactory.getLog(BindingReflectionHintsRegistrar.class);
+
+	private static final Consumer<ExecutableHint.Builder> INVOKE = builder -> builder
+			.withMode(ExecutableMode.INVOKE);
+
+	private static final String KOTLIN_COMPANION_SUFFIX = "$Companion";
+
+	/**
+	 * Register the necessary reflection hints to bind the specified types.
+	 * @param hints the hints instance to use
+	 * @param types the types to bind
+	 */
+	public void registerReflectionHints(ReflectionHints hints, Type... types) {
+		Set<Type> seen = new LinkedHashSet<>();
+		for (Type type : types) {
+			registerReflectionHints(hints, seen, type);
+		}
+	}
+
+	/**
+	 * Return whether the members of the type should be registered transitively.
+	 * @param type the type to evaluate
+	 * @return {@code true} if the members of the type should be registered transitively
+	 */
+	protected boolean shouldRegisterMembers(Class<?> type) {
+		return !type.getCanonicalName().startsWith("java.") && !type.isArray();
+	}
+
+	private void registerReflectionHints(ReflectionHints hints, Set<Type> seen, Type type) {
+		if (type instanceof Class<?> clazz) {
+			if (clazz.isPrimitive() || clazz == Object.class) {
+				return;
+			}
+			hints.registerType(clazz, builder -> {
+				if (seen.contains(type)) {
+					return;
+				}
+				seen.add(type);
+				if (shouldRegisterMembers(clazz)) {
+					if (clazz.isRecord()) {
+						builder.withMembers(MemberCategory.INVOKE_DECLARED_CONSTRUCTORS);
+						for (RecordComponent recordComponent : clazz.getRecordComponents()) {
+							registerRecordHints(hints, seen, recordComponent.getAccessor());
+						}
+					}
+					else {
+						builder.withMembers(
+								MemberCategory.DECLARED_FIELDS,
+								MemberCategory.INVOKE_DECLARED_CONSTRUCTORS);
+						try {
+							BeanInfo beanInfo = Introspector.getBeanInfo(clazz);
+							PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors();
+							for (PropertyDescriptor propertyDescriptor : propertyDescriptors) {
+								registerPropertyHints(hints, seen, propertyDescriptor.getWriteMethod(), 0);
+								registerPropertyHints(hints, seen, propertyDescriptor.getReadMethod(), -1);
+							}
+						}
+						catch (IntrospectionException ex) {
+							if (logger.isDebugEnabled()) {
+								logger.debug("Ignoring referenced type [" + clazz.getName() + "]: " + ex.getMessage());
+							}
+						}
+					}
+				}
+				if (KotlinDetector.isKotlinType(clazz)) {
+					registerKotlinSerializationHints(hints, clazz);
+				}
+			});
+		}
+		Set<Class<?>> referencedTypes = new LinkedHashSet<>();
+		collectReferencedTypes(seen, referencedTypes, type);
+		referencedTypes.forEach(referencedType -> registerReflectionHints(hints, seen, referencedType));
+	}
+
+	private void registerRecordHints(ReflectionHints hints, Set<Type> seen, Method method) {
+		hints.registerMethod(method, INVOKE);
+		MethodParameter methodParameter = MethodParameter.forExecutable(method, -1);
+		Type methodParameterType = methodParameter.getGenericParameterType();
+		if (!seen.contains(methodParameterType)) {
+			registerReflectionHints(hints, seen, methodParameterType);
+		}
+	}
+
+	private void registerPropertyHints(ReflectionHints hints, Set<Type> seen, @Nullable Method method, int parameterIndex) {
+		if (method != null && method.getDeclaringClass() != Object.class
+				&& method.getDeclaringClass() != Enum.class) {
+			hints.registerMethod(method, INVOKE);
+			MethodParameter methodParameter = MethodParameter.forExecutable(method, parameterIndex);
+			Type methodParameterType = methodParameter.getGenericParameterType();
+			if (!seen.contains(methodParameterType)) {
+				registerReflectionHints(hints, seen, methodParameterType);
+			}
+		}
+	}
+
+	private void registerKotlinSerializationHints(ReflectionHints hints, Class<?> clazz) {
+		String companionClassName = clazz.getCanonicalName() + KOTLIN_COMPANION_SUFFIX;
+		if (ClassUtils.isPresent(companionClassName, null)) {
+			Class<?> companionClass = ClassUtils.resolveClassName(companionClassName, null);
+			Method serializerMethod = ClassUtils.getMethodIfAvailable(companionClass, "serializer");
+			if (serializerMethod != null) {
+				hints.registerMethod(serializerMethod);
+			}
+		}
+	}
+
+	private void collectReferencedTypes(Set<Type> seen, Set<Class<?>> types, Type type) {
+		if (seen.contains(type)) {
+			return;
+		}
+		ResolvableType resolvableType = ResolvableType.forType(type);
+		Class<?> clazz = resolvableType.resolve();
+		if (clazz != null && !types.contains(clazz)) {
+			types.add(clazz);
+			for (ResolvableType genericResolvableType : resolvableType.getGenerics()) {
+				collectReferencedTypes(seen, types, genericResolvableType.getType());
+			}
+		}
+	}
+
+}