diff --git a/spring-messaging/src/test/java/org/springframework/messaging/protobuf/OuterSample.java b/spring-messaging/src/test/java/org/springframework/messaging/protobuf/OuterSample.java
index cfb70c16feb..463efe67acf 100644
--- a/spring-messaging/src/test/java/org/springframework/messaging/protobuf/OuterSample.java
+++ b/spring-messaging/src/test/java/org/springframework/messaging/protobuf/OuterSample.java
@@ -1,3 +1,19 @@
+/*
+ * Copyright 2002-2023 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.
+ */
+
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: sample.proto
 
@@ -28,16 +44,10 @@ public class OuterSample {
       descriptor;
   static {
     java.lang.String[] descriptorData = {
-			"""
-
-\014sample.proto",
-\003Msg\022\013
-\003foo\030\001 \001(\t\022\030
-\004blah\030\002 \001(\0132
-.SecondMsg"\031
-\tSecondMsg\022\014
-\004blah\030\001 \001(\005B-
-\034org.springframework.protobufB\013OuterSampleP\001"""
+      "\n\014sample.proto\",\n\003Msg\022\013\n\003foo\030\001 \001(\t\022\030\n\004bl" +
+      "ah\030\002 \001(\0132\n.SecondMsg\"\031\n\tSecondMsg\022\014\n\004bla" +
+      "h\030\001 \001(\005B-\n\034org.springframework.protobufB" +
+      "\013OuterSampleP\001"
     };
     com.google.protobuf.Descriptors.FileDescriptor.InternalDescriptorAssigner assigner =
       new com.google.protobuf.Descriptors.FileDescriptor.InternalDescriptorAssigner() {
diff --git a/spring-web/src/test/java/org/springframework/http/codec/ServerSentEventHttpMessageReaderTests.java b/spring-web/src/test/java/org/springframework/http/codec/ServerSentEventHttpMessageReaderTests.java
index af5cdea4c08..01b203e3d42 100644
--- a/spring-web/src/test/java/org/springframework/http/codec/ServerSentEventHttpMessageReaderTests.java
+++ b/spring-web/src/test/java/org/springframework/http/codec/ServerSentEventHttpMessageReaderTests.java
@@ -66,25 +66,8 @@ class ServerSentEventHttpMessageReaderTests extends AbstractLeakCheckingTests {
 	void readServerSentEvents() {
 		MockServerHttpRequest request = MockServerHttpRequest.post("/")
 				.body(Mono.just(stringBuffer(
-						"""
-								id:c42
-								event:foo
-								retry:123
-								:bla
-								:bla bla
-								:bla bla bla
-								data:bar
-
-								id:c43
-								event:bar
-								retry:456
-								data:baz
-
-								data:
-
-								data:\s
-
-								""")));
+						"id:c42\nevent:foo\nretry:123\n:bla\n:bla bla\n:bla bla bla\ndata:bar\n\n" +
+						"id:c43\nevent:bar\nretry:456\ndata:baz\n\ndata:\n\ndata: \n\n")));
 
 		Flux<ServerSentEvent> events = this.reader
 				.read(ResolvableType.forClassWithGenerics(ServerSentEvent.class, String.class),
diff --git a/spring-web/src/test/java/org/springframework/protobuf/OuterSample.java b/spring-web/src/test/java/org/springframework/protobuf/OuterSample.java
index 4f423a9b074..dbfb1b47323 100644
--- a/spring-web/src/test/java/org/springframework/protobuf/OuterSample.java
+++ b/spring-web/src/test/java/org/springframework/protobuf/OuterSample.java
@@ -1,3 +1,19 @@
+/*
+ * Copyright 2002-2023 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.
+ */
+
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: sample.proto
 
@@ -33,16 +49,10 @@ public final class OuterSample {
       descriptor;
   static {
     String[] descriptorData = {
-			"""
-
-\014sample.proto",
-\003Msg\022\013
-\003foo\030\001 \001(\t\022\030
-\004blah\030\002 \001(\0132
-.SecondMsg"\031
-\tSecondMsg\022\014
-\004blah\030\001 \001(\005B-
-\034org.springframework.protobufB\013OuterSampleP\001"""
+      "\n\014sample.proto\",\n\003Msg\022\013\n\003foo\030\001 \001(\t\022\030\n\004bl" +
+      "ah\030\002 \001(\0132\n.SecondMsg\"\031\n\tSecondMsg\022\014\n\004bla" +
+      "h\030\001 \001(\005B-\n\034org.springframework.protobufB" +
+      "\013OuterSampleP\001"
     };
     descriptor = com.google.protobuf.Descriptors.FileDescriptor
       .internalBuildGeneratedFileFrom(descriptorData,
diff --git a/spring-webflux/src/test/java/org/springframework/web/reactive/function/BodyInsertersTests.java b/spring-webflux/src/test/java/org/springframework/web/reactive/function/BodyInsertersTests.java
index ab3e44076ff..3ef308247a9 100644
--- a/spring-webflux/src/test/java/org/springframework/web/reactive/function/BodyInsertersTests.java
+++ b/spring-webflux/src/test/java/org/springframework/web/reactive/function/BodyInsertersTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2023 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.
diff --git a/spring-webflux/src/test/java/org/springframework/web/reactive/protobuf/OuterSample.java b/spring-webflux/src/test/java/org/springframework/web/reactive/protobuf/OuterSample.java
index da713509f77..3f1b1ecf9f2 100644
--- a/spring-webflux/src/test/java/org/springframework/web/reactive/protobuf/OuterSample.java
+++ b/spring-webflux/src/test/java/org/springframework/web/reactive/protobuf/OuterSample.java
@@ -1,3 +1,19 @@
+/*
+ * Copyright 2002-2023 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.
+ */
+
 // Generated by the protocol buffer compiler.  DO NOT EDIT!
 // source: sample.proto
 
@@ -28,16 +44,10 @@ public class OuterSample {
       descriptor;
   static {
     String[] descriptorData = {
-			"""
-
-\014sample.proto",
-\003Msg\022\013
-\003foo\030\001 \001(\t\022\030
-\004blah\030\002 \001(\0132
-.SecondMsg"\031
-\tSecondMsg\022\014
-\004blah\030\001 \001(\005B-
-\034org.springframework.protobufB\013OuterSampleP\001"""
+      "\n\014sample.proto\",\n\003Msg\022\013\n\003foo\030\001 \001(\t\022\030\n\004bl" +
+      "ah\030\002 \001(\0132\n.SecondMsg\"\031\n\tSecondMsg\022\014\n\004bla" +
+      "h\030\001 \001(\005B-\n\034org.springframework.protobufB" +
+      "\013OuterSampleP\001"
     };
     com.google.protobuf.Descriptors.FileDescriptor.InternalDescriptorAssigner assigner =
       new com.google.protobuf.Descriptors.FileDescriptor.InternalDescriptorAssigner() {