ResponseEntityExceptionHandler handles AsyncRequestNotUsableException

Closes gh-33225

Author: rstoyanchev

spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ResponseEntityExceptionHandler.java

@@ -48,6 +48,7 @@
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.context.request.ServletWebRequest;
 import org.springframework.web.context.request.WebRequest;
+import org.springframework.web.context.request.async.AsyncRequestNotUsableException;
 import org.springframework.web.context.request.async.AsyncRequestTimeoutException;
 import org.springframework.web.method.annotation.HandlerMethodValidationException;
 import org.springframework.web.multipart.MaxUploadSizeExceededException;
@@ -135,7 +136,8 @@ protected MessageSource getMessageSource() {
 			HttpMessageNotReadableException.class,
 			HttpMessageNotWritableException.class,
 			MethodValidationException.class,
-			BindException.class
+			BindException.class,
+			AsyncRequestNotUsableException.class
 		})
 	@Nullable
 	public final ResponseEntity<Object> handleException(Exception ex, WebRequest request) throws Exception {
@@ -197,8 +199,11 @@ else if (ex instanceof HttpMessageNotReadableException theEx) {
 		else if (ex instanceof HttpMessageNotWritableException theEx) {
 			return handleHttpMessageNotWritable(theEx, headers, HttpStatus.INTERNAL_SERVER_ERROR, request);
 		}
-		else if (ex instanceof MethodValidationException subEx) {
-			return handleMethodValidationException(subEx, headers, HttpStatus.INTERNAL_SERVER_ERROR, request);
+		else if (ex instanceof MethodValidationException theEx) {
+			return handleMethodValidationException(theEx, headers, HttpStatus.INTERNAL_SERVER_ERROR, request);
+		}
+		else if (ex instanceof AsyncRequestNotUsableException theEx) {
+			return handleAsyncRequestNotUsableException(theEx, request);
 		}
 		else {
 			// Unknown exception, typically a wrapper with a common MVC exception as cause
@@ -568,6 +573,22 @@ protected ResponseEntity<Object> handleMethodValidationException(
 		return handleExceptionInternal(ex, body, headers, status, request);
 	}
 
+	/**
+	 * Customize the handling of {@link AsyncRequestNotUsableException}.
+	 * <p>By default, return {@code null} since the response is not usable.
+	 * @param ex the exception to handle
+	 * @param request the current request
+	 * @return a {@code ResponseEntity} for the response to use, possibly
+	 * {@code null} when the response is already committed
+	 * @since 6.2
+	 */
+	@Nullable
+	protected ResponseEntity<Object> handleAsyncRequestNotUsableException(
+			AsyncRequestNotUsableException ex, WebRequest request) {
+
+		return null;
+	}
+
 	/**
 	 * Convenience method to create a {@link ProblemDetail} for any exception
 	 * that doesn't implement {@link ErrorResponse}, also performing a

spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/method/annotation/ResponseEntityExceptionHandlerTests.java

@@ -57,6 +57,7 @@
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.context.request.ServletWebRequest;
 import org.springframework.web.context.request.WebRequest;
+import org.springframework.web.context.request.async.AsyncRequestNotUsableException;
 import org.springframework.web.context.request.async.AsyncRequestTimeoutException;
 import org.springframework.web.context.support.StaticWebApplicationContext;
 import org.springframework.web.method.annotation.HandlerMethodValidationException;
@@ -107,10 +108,6 @@ void supportsAllDefaultHandlerExceptionResolverExceptionTypes() throws Exception
 				.filter(method -> method.getName().startsWith("handle") && (method.getParameterCount() == 4))
 				.filter(method -> !method.getName().equals("handleErrorResponse"))
 				.map(method -> method.getParameterTypes()[0])
-				.filter(exceptionType -> {
-					String name = exceptionType.getSimpleName();
-					return !name.equals("AsyncRequestNotUsableException");
-				})
 				.forEach(exceptionType -> assertThat(annotation.value())
 						.as("@ExceptionHandler is missing declaration for " + exceptionType.getName())
 						.contains((Class<Exception>) exceptionType));
@@ -316,6 +313,13 @@ void asyncRequestTimeoutException() {
 		testException(new AsyncRequestTimeoutException());
 	}
 
+	@Test
+	void asyncRequestNotUsableException() throws Exception {
+		AsyncRequestNotUsableException ex = new AsyncRequestNotUsableException("simulated failure");
+		ResponseEntity<Object> entity = this.exceptionHandler.handleException(ex, this.request);
+		assertThat(entity).isNull();
+	}
+
 	@Test
 	void maxUploadSizeExceededException() {
 		testException(new MaxUploadSizeExceededException(1000));