Add dynamic ObjectToObjectConverter hints

This commit refines BindingReflectionHintsRegistrar with additional
dynamic hints for application-defined types, main core Java conversion
ones being already covered by ObjectToObjectConverterRuntimeHints.

Closes gh-35847

spring-core/src/main/java/org/springframework/aot/hint/BindingReflectionHintsRegistrar.java

@@ -20,6 +20,7 @@ import java.lang.annotation.Annotation;
 import java.lang.reflect.AnnotatedElement;
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
 import java.lang.reflect.RecordComponent;
 import java.lang.reflect.Type;
 import java.util.HashSet;
@@ -116,6 +117,7 @@ public class BindingReflectionHintsRegistrar {
 					if (JACKSON_ANNOTATION_PRESENT) {
 						registerJacksonHints(hints, clazz);
 					}
+					registerObjectToObjectConverterHints(hints, clazz);
 				}
 				if (KotlinDetector.isKotlinType(clazz)) {
 					KotlinDelegate.registerComponentHints(hints, clazz);
@@ -156,6 +158,25 @@ public class BindingReflectionHintsRegistrar {
 		}
 	}
 
+	// See also the static hints registered by ObjectToObjectConverterRuntimeHints
+	private void registerObjectToObjectConverterHints(ReflectionHints hints, Class<?> clazz) {
+		for (Method method : clazz.getMethods()) {
+			String name = method.getName();
+			boolean isStatic = Modifier.isStatic(method.getModifiers());
+			if (isStatic && (clazz != String.class) && areRelatedTypes(method.getReturnType(), clazz) &&
+					(name.equals("valueOf") || name.equals("of") || name.equals("from"))) {
+					hints.registerMethod(method, ExecutableMode.INVOKE);
+			}
+			if (!isStatic && (method.getReturnType() != String.class) && name.equals("to" + method.getReturnType().getSimpleName())) {
+				hints.registerMethod(method, ExecutableMode.INVOKE);
+			}
+		}
+	}
+
+	private static boolean areRelatedTypes(Class<?> type1, Class<?> type2) {
+		return (ClassUtils.isAssignable(type1, type2) || ClassUtils.isAssignable(type2, type1));
+	}
+
 	private void collectReferencedTypes(Set<Class<?>> types, ResolvableType resolvableType) {
 		Class<?> clazz = resolvableType.resolve();
 		if (clazz != null && !types.contains(clazz)) {

spring-core/src/main/java/org/springframework/aot/hint/support/ObjectToObjectConverterRuntimeHints.java

@@ -23,6 +23,7 @@ import java.util.List;
 
 import org.jspecify.annotations.Nullable;
 
+import org.springframework.aot.hint.BindingReflectionHintsRegistrar;
 import org.springframework.aot.hint.ExecutableMode;
 import org.springframework.aot.hint.MemberCategory;
 import org.springframework.aot.hint.ReflectionHints;
@@ -33,6 +34,7 @@ import org.springframework.aot.hint.TypeReference;
 /**
  * {@link RuntimeHintsRegistrar} to register hints for popular conventions in
  * {@code org.springframework.core.convert.support.ObjectToObjectConverter}.
+ * Some dynamic hints registered by {@link BindingReflectionHintsRegistrar}.
  *
  * @author Sebastien Deleuze
  * @author Sam Brannen

spring-core/src/test/java/org/springframework/aot/hint/BindingReflectionHintsRegistrarTests.java

@@ -31,6 +31,7 @@ import com.fasterxml.jackson.databind.annotation.JsonPOJOBuilder;
 import com.fasterxml.jackson.databind.deser.std.StdDeserializer;
 import org.junit.jupiter.api.Test;
 
+import org.springframework.aot.hint.predicate.ReflectionHintsPredicates;
 import org.springframework.aot.hint.predicate.RuntimeHintsPredicates;
 import org.springframework.core.ResolvableType;
 
@@ -301,6 +302,16 @@ class BindingReflectionHintsRegistrarTests {
 				.accepts(this.hints);
 	}
 
+	@Test
+	void registerTypeForObjectToObjectConverter() {
+		bindingRegistrar.registerReflectionHints(this.hints.reflection(), Source.class);
+		ReflectionHintsPredicates reflection = RuntimeHintsPredicates.reflection();
+		assertThat(reflection.onMethodInvocation(Source.class, "valueOf")).accepts(this.hints);
+		assertThat(reflection.onMethodInvocation(Source.class, "of")).accepts(this.hints);
+		assertThat(reflection.onMethodInvocation(Source.class, "from")).accepts(this.hints);
+		assertThat(reflection.onMethodInvocation(Source.class, "toData")).accepts(this.hints);
+	}
+
 
 	static class SampleEmptyClass {
 	}
@@ -460,4 +471,31 @@ class BindingReflectionHintsRegistrarTests {
 		}
 	}
 
+	static class Source {
+
+		private final String value;
+
+		private Source(String value) {
+			this.value = value;
+		}
+
+		public static Source valueOf(String value) {
+			return new Source(value);
+		}
+
+		public static Source of(String value) {
+			return new Source(value);
+		}
+
+		public static Source from(String value) {
+			return new Source(value);
+		}
+
+		public Data toData() {
+			return new Data(this.value);
+		}
+	}
+
+	record Data(String value) { }
+
 }