diff --git a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaMessageConverterTests.java b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaMessageConverterTests.java
index 150525c23..019e26aba 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaMessageConverterTests.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaMessageConverterTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2019 the original author or authors.
+ * Copyright 2016-2023 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.
@@ -44,7 +44,7 @@ import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
 /**
  * @author Marius Bogoevici
  */
-public class AvroSchemaMessageConverterTests {
+class AvroSchemaMessageConverterTests {
 
 	static StubSchemaRegistryClient stubSchemaRegistryClient = new StubSchemaRegistryClient();
 
diff --git a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaServiceManagerTests.java b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaServiceManagerTests.java
index a7a2b0584..586abf1fd 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaServiceManagerTests.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaServiceManagerTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2019 the original author or authors.
+ * Copyright 2017-2023 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.
@@ -51,7 +51,7 @@ import static org.assertj.core.api.Assertions.fail;
 /**
  * @author Ish Mahajan
  */
-public class AvroSchemaServiceManagerTests {
+class AvroSchemaServiceManagerTests {
 
 	private final Log logger = LogFactory.getLog(AvroSchemaServiceManagerTests.class);
 
diff --git a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaWithMultipleRecordsTest.java b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaWithMultipleRecordsTest.java
index 0e1057e2b..085efe5ef 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaWithMultipleRecordsTest.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/AvroSchemaWithMultipleRecordsTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2020-2022 the original author or authors.
+ * Copyright 2020-2023 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.
@@ -49,7 +49,7 @@ import static org.assertj.core.api.Assertions.assertThat;
 /**
  * @author Christian Tzolov
  */
-public class AvroSchemaWithMultipleRecordsTest {
+class AvroSchemaWithMultipleRecordsTest {
 
 	@Test
 	public void schemaLocationWithMultipleRecords() throws Exception {
diff --git a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/SubjectNamingStrategyTest.java b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/SubjectNamingStrategyTest.java
index 244cdeff1..8c9f9e409 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/SubjectNamingStrategyTest.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/SubjectNamingStrategyTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2019 the original author or authors.
+ * Copyright 2016-2023 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.
@@ -45,7 +45,7 @@ import static org.assertj.core.api.Assertions.assertThat;
  * @author José A. Íñigo
  * @author Christian Tzolov
  */
-public class SubjectNamingStrategyTest {
+class SubjectNamingStrategyTest {
 
 	private static StubSchemaRegistryClient stubSchemaRegistryClient = new StubSchemaRegistryClient();
 
diff --git a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/client/ConfluentSchemaRegistryClientTests.java b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/client/ConfluentSchemaRegistryClientTests.java
index fb3c0a1c9..2dcbaac98 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/client/ConfluentSchemaRegistryClientTests.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/avro/client/ConfluentSchemaRegistryClientTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2019 the original author or authors.
+ * Copyright 2017-2023 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.
@@ -43,7 +43,7 @@ import static org.springframework.test.web.client.response.MockRestResponseCreat
  * @author Vinicius Carvalho
  * @author TengZhou Dong
  */
-public class ConfluentSchemaRegistryClientTests {
+class ConfluentSchemaRegistryClientTests {
 
 	private RestTemplate restTemplate;
 
diff --git a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/serialization/AvroMessageConverterSerializationTests.java b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/serialization/AvroMessageConverterSerializationTests.java
index 91e33b484..a8650aa29 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/serialization/AvroMessageConverterSerializationTests.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/serialization/AvroMessageConverterSerializationTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2017-2019 the original author or authors.
+ * Copyright 2017-2023 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.
@@ -65,7 +65,7 @@ import static org.assertj.core.api.Assertions.assertThat;
  * @author Vinicius Carvalho
  * @author Sercan Karaoglu
  */
-public class AvroMessageConverterSerializationTests {
+class AvroMessageConverterSerializationTests {
 
 	Pattern versionedSchema = Pattern.compile(
 			"application/" + "vnd" + "\\.([\\p{Alnum}\\$\\.]+)\\.v(\\p{Digit}+)\\+avro");
diff --git a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/serialization/AvroSchemaRegistryClientMessageConverterTests.java b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/serialization/AvroSchemaRegistryClientMessageConverterTests.java
index 097bb9902..72b8a2fcc 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/serialization/AvroSchemaRegistryClientMessageConverterTests.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-client/src/test/java/org/springframework/cloud/stream/schema/serialization/AvroSchemaRegistryClientMessageConverterTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2020 the original author or authors.
+ * Copyright 2016-2023 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.
@@ -71,7 +71,7 @@ import static org.springframework.cloud.stream.schema.serialization.AvroMessageC
  * @author James Gee
  * @author Christian Tzolov
  */
-public class AvroSchemaRegistryClientMessageConverterTests {
+class AvroSchemaRegistryClientMessageConverterTests {
 
 
 	private ConfigurableApplicationContext schemaRegistryServerContext;
diff --git a/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/AbstractServerControllerTest.java b/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/AbstractServerControllerTest.java
index fb63d6982..4aafff1b1 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/AbstractServerControllerTest.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/AbstractServerControllerTest.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019-2019 the original author or authors.
+ * Copyright 2019-2023 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.
@@ -35,7 +35,7 @@ import static org.springframework.test.web.servlet.request.MockMvcRequestBuilder
 /**
  * @author Christian Tzolov
  */
-public abstract class AbstractServerControllerTest {
+abstract class AbstractServerControllerTest {
 
 	protected MockMvc mockMvc;
 
diff --git a/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/EntityScanningTests.java b/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/EntityScanningTests.java
index 0bbb70fe7..6d13b27a7 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/EntityScanningTests.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/EntityScanningTests.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2019 the original author or authors.
+ * Copyright 2016-2023 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.
@@ -27,7 +27,7 @@ import org.springframework.context.ConfigurableApplicationContext;
 /**
  * @author Marius Bogoevici
  */
-public class EntityScanningTests {
+class EntityScanningTests {
 
 	@Test
 	public void testApplicationWithEmbeddedSchemaRegistryServerOutsideOfRootPackage()
diff --git a/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/EntityScanningTestsWithEntityScan.java b/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/EntityScanningTestsWithEntityScan.java
index 4f9cdae20..63c89d01a 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/EntityScanningTestsWithEntityScan.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/EntityScanningTestsWithEntityScan.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2019 the original author or authors.
+ * Copyright 2016-2023 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.
@@ -28,7 +28,7 @@ import org.springframework.context.ConfigurableApplicationContext;
 /**
  * @author Marius Bogoevici
  */
-public class EntityScanningTestsWithEntityScan {
+class EntityScanningTestsWithEntityScan {
 
 	@Test
 	public void testApplicationWithEmbeddedSchemaRegistryServerOutsideOfRootPackage() {
diff --git a/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/ServerControllerTest.java b/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/ServerControllerTest.java
index 46da2cf71..a80dc2017 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/ServerControllerTest.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-core/src/test/java/org/springframework/cloud/stream/schema/registry/entityScanning/ServerControllerTest.java
@@ -44,7 +44,7 @@ import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.
 		"spring.cloud.stream.schema.server.path=/testpath",
 		"spring.cloud.stream.schema.server.allowSchemaDeletion=false"
 })
-public class ServerControllerTest extends AbstractServerControllerTest {
+class ServerControllerTest extends AbstractServerControllerTest {
 
 	@Test
 	public void propertiesTest() {
diff --git a/schema-registry/spring-cloud-stream-schema-registry-server/src/test/java/org/springframework/cloud/stream/schema/registry/server/SchemaRegistryServerAvroTests.java b/schema-registry/spring-cloud-stream-schema-registry-server/src/test/java/org/springframework/cloud/stream/schema/registry/server/SchemaRegistryServerAvroTests.java
index 56bf6d276..8bb26e368 100644
--- a/schema-registry/spring-cloud-stream-schema-registry-server/src/test/java/org/springframework/cloud/stream/schema/registry/server/SchemaRegistryServerAvroTests.java
+++ b/schema-registry/spring-cloud-stream-schema-registry-server/src/test/java/org/springframework/cloud/stream/schema/registry/server/SchemaRegistryServerAvroTests.java
@@ -70,7 +70,7 @@ import static org.springframework.test.annotation.DirtiesContext.ClassMode.AFTER
  */
 @SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.DEFINED_PORT, properties = "spring.main.allow-bean-definition-overriding=true")
 @DirtiesContext(classMode = AFTER_EACH_TEST_METHOD)
-public class SchemaRegistryServerAvroTests {
+class SchemaRegistryServerAvroTests {
 
 	private static final String AVRO_FORMAT_NAME = "avro";