Render method parameter annotations in AOT repositories.

We now include annotations of repository query method parameters to allow introspection through Parameters for reflective checks.

See spring-projects/spring-data-relational#2245

src/main/java/org/springframework/data/repository/aot/generate/MethodMetadata.java

@@ -15,6 +15,7 @@
  */
 package org.springframework.data.repository.aot.generate;
 
+import java.lang.annotation.Annotation;
 import java.lang.reflect.Method;
 import java.lang.reflect.Parameter;
 import java.util.ArrayList;
@@ -29,9 +30,12 @@ import org.jspecify.annotations.Nullable;
 
 import org.springframework.core.MethodParameter;
 import org.springframework.core.ResolvableType;
+import org.springframework.core.annotation.MergedAnnotation;
+import org.springframework.core.annotation.MergedAnnotations;
 import org.springframework.data.core.TypeInformation;
 import org.springframework.data.javapoet.TypeNames;
 import org.springframework.data.repository.core.RepositoryInformation;
+import org.springframework.javapoet.AnnotationSpec;
 import org.springframework.javapoet.ParameterSpec;
 import org.springframework.javapoet.TypeName;
 import org.springframework.util.Assert;
@@ -87,7 +91,7 @@ class MethodMetadata {
 			TypeName parameterType = parameterTypeName(methodParameter, repositoryInterfaceType);
 
 			Assert.notNull(methodParameter.getParameterName(), "MethodParameter.getParameterName() must not be null");
-			ParameterSpec parameterSpec = ParameterSpec.builder(parameterType, methodParameter.getParameterName()).build();
+			ParameterSpec parameterSpec = buildParameter(parameterType, methodParameter);
 
 			if (methodArguments.containsKey(parameterSpec.name())) {
 				throw new IllegalStateException("Parameter with name '" + parameterSpec.name() + "' already exists.");
@@ -98,7 +102,19 @@ class MethodMetadata {
 		}
 	}
 
-    @SuppressWarnings("NullAway")
+	private static ParameterSpec buildParameter(TypeName parameterType, MethodParameter methodParameter) {
+
+		ParameterSpec.Builder builder = ParameterSpec.builder(parameterType, methodParameter.getParameterName());
+		MergedAnnotations annotations = MergedAnnotations.from(methodParameter.getParameterAnnotations());
+
+		for (MergedAnnotation<Annotation> annotation : annotations) {
+			builder.addAnnotation(AnnotationSpec.get(annotation.synthesize()));
+		}
+
+		return builder.build();
+	}
+
+	@SuppressWarnings("NullAway")
 	static TypeName parameterTypeName(MethodParameter methodParameter, Class<?> repositoryInterface) {
 
 		ResolvableType resolvableParameterType = ResolvableType.forMethodParameter(methodParameter);

src/test/java/example/UserRepository.java

@@ -20,13 +20,14 @@ import example.UserRepository.User;
 import java.util.List;
 
 import org.springframework.data.repository.CrudRepository;
+import org.springframework.data.repository.query.Param;
 
 /**
  * @author Christoph Strobl
  */
 public interface UserRepository extends CrudRepository<User, Long>, UserRepositoryExtension {
 
-	User findByFirstname(String firstname);
+	User findByFirstname(@Param("hello") String firstname);
 
 	List<User> findByFirstnameIn(List<String> firstnames);
 

src/test/java/org/springframework/data/repository/aot/generate/AotRepositoryMethodBuilderUnitTests.java

@@ -55,7 +55,7 @@ class AotRepositoryMethodBuilderUnitTests {
 		when(methodGenerationContext.getExpressionMarker()).thenReturn(new ExpressionMarker());
 	}
 
-	@Test // GH-3279
+	@Test // GH-3279, GH-3458
 	void generatesMethodSkeletonBasedOnGenerationMetadata() throws NoSuchMethodException {
 
 		Method method = UserRepository.class.getMethod("findByFirstname", String.class);
@@ -66,8 +66,8 @@ class AotRepositoryMethodBuilderUnitTests {
 		when(methodGenerationContext.getTargetMethodMetadata()).thenReturn(methodMetadata);
 
 		AotRepositoryMethodBuilder builder = new AotRepositoryMethodBuilder(methodGenerationContext);
-		assertThat(builder.buildMethod().toString()) //
-				.containsPattern("public .*User findByFirstname\\(.*String firstname\\)");
+		assertThat(builder.buildMethod().toString().replaceAll(System.lineSeparator(), " ")) //
+				.containsPattern("findByFirstname\\(.*@.*Param\\(\"hello\"\\).*String firstname\\)");
 	}
 
 	@Test // GH-3279

src/test/java/org/springframework/data/repository/aot/generate/MethodMetadataUnitTests.java

@@ -26,6 +26,8 @@ import org.mockito.Mockito;
 import org.springframework.data.core.TypeInformation;
 import org.springframework.data.domain.Pageable;
 import org.springframework.data.repository.core.RepositoryInformation;
+import org.springframework.data.repository.query.Param;
+import org.springframework.javapoet.ParameterSpec;
 
 /**
  * Unit tests for {@link MethodMetadata}.
@@ -44,6 +46,15 @@ class MethodMetadataUnitTests {
 		assertThat(metadata.getParameterName(2)).isEqualTo("arg2");
 	}
 
+	@Test // GH-3458
+	void addsAnnotations() throws NoSuchMethodException {
+
+		MethodMetadata metadata = methodMetadataFor("threeArgsMethod");
+
+		ParameterSpec spec = metadata.getMethodArguments().get("arg2");
+		assertThat(spec.annotations()).hasSize(1);
+	}
+
 	@Test // GH-3270
 	void getParameterNameByNonExistingIndex() throws NoSuchMethodException {
 
@@ -82,6 +93,6 @@ class MethodMetadataUnitTests {
 
 		String noArgsMethod();
 
-		String threeArgsMethod(Object arg0, Pageable arg1, Object arg2);
+		String threeArgsMethod(Object arg0, Pageable arg1, @Param("foo") Object arg2);
 	}
 }