Merge pull request #34503 from vy

* gh-34503:
  Polish "Allow ProblemDetailsExceptionHandlers to be proxied"
  Allow ProblemDetailsExceptionHandlers to be proxied

Closes gh-34503

Author: wilkinsona

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/reactive/ProblemDetailsExceptionHandler.java

@@ -26,6 +26,6 @@
  * @author Brian Clozel
  */
 @ControllerAdvice
-final class ProblemDetailsExceptionHandler extends ResponseEntityExceptionHandler {
+class ProblemDetailsExceptionHandler extends ResponseEntityExceptionHandler {
 
 }

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/servlet/ProblemDetailsExceptionHandler.java

@@ -26,6 +26,6 @@
  * @author Brian Clozel
  */
 @ControllerAdvice
-final class ProblemDetailsExceptionHandler extends ResponseEntityExceptionHandler {
+class ProblemDetailsExceptionHandler extends ResponseEntityExceptionHandler {
 
 }

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/reactive/WebFluxAutoConfigurationTests.java

@@ -32,12 +32,17 @@
 import java.util.function.Consumer;
 
 import jakarta.validation.ValidatorFactory;
+import org.aspectj.lang.JoinPoint;
+import org.aspectj.lang.annotation.AfterReturning;
+import org.aspectj.lang.annotation.Aspect;
 import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
 
+import org.springframework.aop.support.AopUtils;
 import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.autoconfigure.aop.AopAutoConfiguration;
 import org.springframework.boot.autoconfigure.validation.ValidationAutoConfiguration;
 import org.springframework.boot.autoconfigure.validation.ValidatorAdapter;
 import org.springframework.boot.autoconfigure.web.ServerProperties;
@@ -645,6 +650,17 @@ void problemDetailsEnabledAddsExceptionHandler() {
 			.run((context) -> assertThat(context).hasSingleBean(ProblemDetailsExceptionHandler.class));
 	}
 
+	@Test
+	void problemDetailsExceptionHandlerDoesNotPreventProxying() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(AopAutoConfiguration.class))
+			.withBean(ExceptionHandlerInterceptor.class)
+			.withPropertyValues("spring.webflux.problemdetails.enabled:true")
+			.run((context) -> {
+				assertThat(context).hasSingleBean(ProblemDetailsExceptionHandler.class);
+				assertThat(AopUtils.isCglibProxy(context.getBean(ProblemDetailsExceptionHandler.class)));
+			});
+	}
+
 	@Test
 	void problemDetailsBacksOffWhenExceptionHandler() {
 		this.contextRunner.withPropertyValues("spring.webflux.problemdetails.enabled:true")
@@ -957,4 +973,14 @@ static class CustomExceptionHandler extends ResponseEntityExceptionHandler {
 
 	}
 
+	@Aspect
+	static class ExceptionHandlerInterceptor {
+
+		@AfterReturning(pointcut = "@annotation(org.springframework.web.bind.annotation.ExceptionHandler)",
+				returning = "returnValue")
+		void exceptionHandlerIntercept(JoinPoint joinPoint, Object returnValue) {
+		}
+
+	}
+
 }

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfigurationTests.java

@@ -36,9 +36,14 @@
 import jakarta.servlet.http.HttpServletRequest;
 import jakarta.servlet.http.HttpServletResponse;
 import jakarta.validation.ValidatorFactory;
+import org.aspectj.lang.JoinPoint;
+import org.aspectj.lang.annotation.AfterReturning;
+import org.aspectj.lang.annotation.Aspect;
 import org.junit.jupiter.api.Test;
 
+import org.springframework.aop.support.AopUtils;
 import org.springframework.boot.autoconfigure.AutoConfigurations;
+import org.springframework.boot.autoconfigure.aop.AopAutoConfiguration;
 import org.springframework.boot.autoconfigure.context.PropertyPlaceholderAutoConfiguration;
 import org.springframework.boot.autoconfigure.http.HttpMessageConverters;
 import org.springframework.boot.autoconfigure.http.HttpMessageConvertersAutoConfiguration;
@@ -988,6 +993,17 @@ void problemDetailsEnabledAddsExceptionHandler() {
 			.run((context) -> assertThat(context).hasSingleBean(ProblemDetailsExceptionHandler.class));
 	}
 
+	@Test
+	void problemDetailsExceptionHandlerDoesNotPreventProxying() {
+		this.contextRunner.withConfiguration(AutoConfigurations.of(AopAutoConfiguration.class))
+			.withBean(ExceptionHandlerInterceptor.class)
+			.withPropertyValues("spring.mvc.problemdetails.enabled:true")
+			.run((context) -> {
+				assertThat(context).hasSingleBean(ProblemDetailsExceptionHandler.class);
+				assertThat(AopUtils.isCglibProxy(context.getBean(ProblemDetailsExceptionHandler.class)));
+			});
+	}
+
 	@Test
 	void problemDetailsBacksOffWhenExceptionHandler() {
 		this.contextRunner.withPropertyValues("spring.mvc.problemdetails.enabled:true")
@@ -1539,4 +1555,14 @@ static class CustomExceptionHandler extends ResponseEntityExceptionHandler {
 
 	}
 
+	@Aspect
+	static class ExceptionHandlerInterceptor {
+
+		@AfterReturning(pointcut = "@annotation(org.springframework.web.bind.annotation.ExceptionHandler)",
+				returning = "returnValue")
+		void exceptionHandlerIntercept(JoinPoint joinPoint, Object returnValue) {
+		}
+
+	}
+
 }