Add ReactiveCrudRepositoryInvoker for reactive repository population.

src/main/java/org/springframework/data/repository/support/DefaultRepositoryInvokerFactory.java

@@ -24,6 +24,7 @@
 import org.springframework.core.convert.ConversionService;
 import org.springframework.data.repository.CrudRepository;
 import org.springframework.data.repository.PagingAndSortingRepository;
+import org.springframework.data.repository.reactive.ReactiveCrudRepository;
 import org.springframework.data.repository.core.RepositoryInformation;
 import org.springframework.format.support.DefaultFormattingConversionService;
 import org.springframework.util.Assert;
@@ -95,7 +96,10 @@ private RepositoryInvoker prepareInvokers(Class<?> domainType) {
 	@SuppressWarnings("unchecked")
 	protected RepositoryInvoker createInvoker(RepositoryInformation information, Object repository) {
 
-		if (repository instanceof PagingAndSortingRepository && repository instanceof CrudRepository) {
+		if (repository instanceof ReactiveCrudRepository) {
+			return new ReactiveCrudRepositoryInvoker((ReactiveCrudRepository<Object, Object>) repository, information,
+					conversionService);
+		} else if (repository instanceof PagingAndSortingRepository && repository instanceof CrudRepository) {
 			return new PagingAndSortingRepositoryInvoker((PagingAndSortingRepository<Object, Object>) repository, information,
 					conversionService);
 		} else if (repository instanceof CrudRepository) {

src/main/java/org/springframework/data/repository/support/ReactiveCrudRepositoryInvoker.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright 2026-present 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.data.repository.support;
+
+import java.lang.reflect.Method;
+import java.util.Optional;
+
+import org.springframework.core.convert.ConversionService;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.domain.Sort;
+import org.springframework.data.repository.core.CrudMethods;
+import org.springframework.data.repository.core.RepositoryMetadata;
+import org.springframework.data.repository.reactive.ReactiveCrudRepository;
+
+/**
+ * {@link RepositoryInvoker} to shortcut execution of CRUD methods into direct calls on a
+ * {@link ReactiveCrudRepository}. This invoker blocks on reactive types to provide synchronous
+ * execution semantics required by the repository populator infrastructure.
+ *
+ * @author Gichan Im
+ * @since 4.1
+ * @see ReactiveCrudRepository
+ */
+class ReactiveCrudRepositoryInvoker extends ReflectionRepositoryInvoker {
+
+	private final ReactiveCrudRepository<Object, Object> repository;
+
+	private final boolean customSaveMethod;
+	private final boolean customFindOneMethod;
+	private final boolean customFindAllMethod;
+	private final boolean customDeleteMethod;
+
+	/**
+	 * Creates a new {@link ReactiveCrudRepositoryInvoker} for the given {@link ReactiveCrudRepository},
+	 * {@link RepositoryMetadata} and {@link ConversionService}.
+	 *
+	 * @param repository must not be {@literal null}.
+	 * @param metadata must not be {@literal null}.
+	 * @param conversionService must not be {@literal null}.
+	 */
+	public ReactiveCrudRepositoryInvoker(ReactiveCrudRepository<Object, Object> repository, RepositoryMetadata metadata,
+			ConversionService conversionService) {
+
+		super(repository, metadata, conversionService);
+
+		CrudMethods crudMethods = metadata.getCrudMethods();
+
+		this.customSaveMethod = isRedeclaredMethod(crudMethods.getSaveMethod());
+		this.customFindOneMethod = isRedeclaredMethod(crudMethods.getFindOneMethod());
+		this.customDeleteMethod = isRedeclaredMethod(crudMethods.getDeleteMethod());
+		this.customFindAllMethod = isRedeclaredMethod(crudMethods.getFindAllMethod());
+		this.repository = repository;
+	}
+
+	@Override
+	public Iterable<Object> invokeFindAll(Sort sort) {
+		return customFindAllMethod ? super.invokeFindAll(sort) : repository.findAll().collectList().block();
+	}
+
+	@Override
+	public Iterable<Object> invokeFindAll(Pageable pageable) {
+		return customFindAllMethod ? super.invokeFindAll(pageable) : repository.findAll().collectList().block();
+	}
+
+	@Override
+	@SuppressWarnings("unchecked")
+	public <T> Optional<T> invokeFindById(Object id) {
+		return customFindOneMethod ? super.invokeFindById(id)
+				: (Optional<T>) repository.findById(convertId(id)).blockOptional();
+	}
+
+	@Override
+	@SuppressWarnings("unchecked")
+	public <T> T invokeSave(T entity) {
+		return customSaveMethod ? super.invokeSave(entity) : (T) repository.save(entity).block();
+	}
+
+	@Override
+	public void invokeDeleteById(Object id) {
+
+		if (customDeleteMethod) {
+			super.invokeDeleteById(id);
+		} else {
+			repository.deleteById(convertId(id)).block();
+		}
+	}
+
+	private static boolean isRedeclaredMethod(Optional<Method> method) {
+		return method.map(it -> !it.getDeclaringClass().equals(ReactiveCrudRepository.class)).orElse(false);
+	}
+}

src/test/java/org/springframework/data/repository/support/ReactiveCrudRepositoryInvokerUnitTests.java

@@ -0,0 +1,138 @@
+/*
+ * Copyright 2026-present 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.data.repository.support;
+
+import static org.mockito.ArgumentMatchers.*;
+import static org.mockito.Mockito.*;
+import static org.springframework.data.repository.support.RepositoryInvocationTestUtils.*;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.mockito.Mock;
+import org.mockito.junit.jupiter.MockitoExtension;
+
+import org.springframework.core.convert.support.GenericConversionService;
+import org.springframework.data.domain.Pageable;
+import org.springframework.data.domain.Sort;
+import org.springframework.data.repository.core.RepositoryMetadata;
+import org.springframework.data.repository.core.support.DefaultRepositoryMetadata;
+import org.springframework.data.repository.reactive.ReactiveCrudRepository;
+import org.springframework.format.support.DefaultFormattingConversionService;
+
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+/**
+ * Unit tests for {@link ReactiveCrudRepositoryInvoker}.
+ *
+ * @author Gichan Im
+ */
+@ExtendWith(MockitoExtension.class)
+class ReactiveCrudRepositoryInvokerUnitTests {
+
+	@Mock ReactivePersonRepository repository;
+	@Mock ReactiveOrderRepository orderRepository;
+
+	@Test // GH-2090
+	void invokesRedeclaredSave() {
+
+		when(orderRepository.save(any())).thenReturn(Mono.just(new Order()));
+
+		getInvokerFor(orderRepository, expectInvocationOnType(ReactiveOrderRepository.class)).invokeSave(new Order());
+	}
+
+	@Test // GH-2090
+	void invokesRedeclaredFindById() {
+
+		when(orderRepository.findById(any(Long.class))).thenReturn(Mono.empty());
+
+		getInvokerFor(orderRepository, expectInvocationOnType(ReactiveOrderRepository.class)).invokeFindById(1L);
+	}
+
+	@Test // GH-2090
+	void invokesRedeclaredDelete() {
+
+		when(orderRepository.deleteById(any(Long.class))).thenReturn(Mono.empty());
+
+		getInvokerFor(orderRepository, expectInvocationOnType(ReactiveOrderRepository.class)).invokeDeleteById(1L);
+	}
+
+	@Test // GH-2090
+	void invokesSaveOnReactiveCrudRepository() throws Exception {
+
+		when(repository.save(any())).thenReturn(Mono.just(new Person()));
+
+		var method = ReactiveCrudRepository.class.getMethod("save", Object.class);
+		getInvokerFor(repository, expectInvocationOf(method)).invokeSave(new Person());
+	}
+
+	@Test // GH-2090
+	void invokesFindByIdOnReactiveCrudRepository() throws Exception {
+
+		when(repository.findById(any(Long.class))).thenReturn(Mono.empty());
+
+		var method = ReactiveCrudRepository.class.getMethod("findById", Object.class);
+		getInvokerFor(repository, expectInvocationOf(method)).invokeFindById(1L);
+	}
+
+	@Test // GH-2090
+	void invokesDeleteByIdOnReactiveCrudRepository() throws Exception {
+
+		when(repository.deleteById(any(Long.class))).thenReturn(Mono.empty());
+
+		var method = ReactiveCrudRepository.class.getMethod("deleteById", Object.class);
+		getInvokerFor(repository, expectInvocationOf(method)).invokeDeleteById(1L);
+	}
+
+	@Test // GH-2090
+	void invokesFindAllOnReactiveCrudRepository() throws Exception {
+
+		when(repository.findAll()).thenReturn(Flux.empty());
+
+		var method = ReactiveCrudRepository.class.getMethod("findAll");
+		getInvokerFor(repository, expectInvocationOf(method)).invokeFindAll(Pageable.unpaged());
+		getInvokerFor(repository, expectInvocationOf(method)).invokeFindAll(Sort.unsorted());
+	}
+
+	@SuppressWarnings({ "rawtypes", "unchecked" })
+	private static RepositoryInvoker getInvokerFor(Object repository, VerifyingMethodInterceptor interceptor) {
+
+		var proxy = getVerifyingRepositoryProxy(repository, interceptor);
+
+		RepositoryMetadata metadata = new DefaultRepositoryMetadata(repository.getClass().getInterfaces()[0]);
+		GenericConversionService conversionService = new DefaultFormattingConversionService();
+
+		return new ReactiveCrudRepositoryInvoker((ReactiveCrudRepository) proxy, metadata, conversionService);
+	}
+
+	static class Person {}
+
+	static class Order {}
+
+	interface ReactivePersonRepository extends ReactiveCrudRepository<Person, Long> {}
+
+	interface ReactiveOrderRepository extends ReactiveCrudRepository<Order, Long> {
+
+		@Override
+		<S extends Order> Mono<S> save(S entity);
+
+		@Override
+		Mono<Order> findById(Long id);
+
+		@Override
+		Mono<Void> deleteById(Long id);
+	}
+}