fix(web): handle HttpMessageNotWritableException in DisconnectedClien…

spring-web/src/main/java/org/springframework/web/util/DisconnectedClientHelper.java

@@ -42,7 +42,8 @@
 public class DisconnectedClientHelper {
 
 	private static final Set<String> EXCEPTION_PHRASES =
-			Set.of("broken pipe", "connection reset by peer");
+			Set.of("broken pipe", "connection reset by peer",
+					"response may not be written");
 
 	private static final Set<String> EXCEPTION_TYPE_NAMES =
 			Set.of("AbortedException", "ClientAbortException",

spring-web/src/test/java/org/springframework/web/util/DisconnectedClientHelperTests.java

@@ -34,6 +34,7 @@
 import org.springframework.web.client.ResourceAccessException;
 import org.springframework.web.context.request.async.AsyncRequestNotUsableException;
 import org.springframework.web.testfixture.http.MockHttpInputMessage;
+import org.springframework.http.converter.HttpMessageNotWritableException;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
@@ -99,4 +100,11 @@ void nullException() {
 		assertThat(DisconnectedClientHelper.isClientDisconnectedException(null)).isFalse();
 	}
 
+	@Test // gh-36421
+	void httpMessageNotWritableFromClosedConnection() {
+		IOException cause = new IOException("The response may not be written to once it has been closed");
+		Exception ex = new HttpMessageNotWritableException("Could not write JSON", cause);
+		assertThat(DisconnectedClientHelper.isClientDisconnectedException(ex)).isTrue();
+	}
+
 }