diff --git a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/AbstractWebClientReactiveOAuth2AccessTokenResponseClient.java b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/AbstractWebClientReactiveOAuth2AccessTokenResponseClient.java
index 8fb5616533d..62dda04a6e6 100644
--- a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/AbstractWebClientReactiveOAuth2AccessTokenResponseClient.java
+++ b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/AbstractWebClientReactiveOAuth2AccessTokenResponseClient.java
@@ -126,7 +126,7 @@ BodyInserters.FormInserter<String> populateTokenRequestBody(T grantRequest, Body
 		if (ClientAuthenticationMethod.POST.equals(clientRegistration.getClientAuthenticationMethod())) {
 			body.with(OAuth2ParameterNames.CLIENT_SECRET, clientRegistration.getClientSecret());
 		}
-		if(ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())){
+		if (ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())){
 			body.with(ClientAssertionParameterNames.CLIENT_ASSERTION_TYPE, ClientAssertionParameterValues.CLIENT_ASSERTION_TYPE_JWT_BEARER);
 			body.with(ClientAssertionParameterNames.CLIENT_ASSERTION, OAuth2AuthorizationGrantRequestEntityUtils.getClientSecretAssertion(clientRegistration).serialize());
 
diff --git a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationCodeGrantRequestEntityConverter.java b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationCodeGrantRequestEntityConverter.java
index 2974901bae2..c9ee3016456 100644
--- a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationCodeGrantRequestEntityConverter.java
+++ b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationCodeGrantRequestEntityConverter.java
@@ -88,7 +88,7 @@ private MultiValueMap<String, String> buildFormParameters(OAuth2AuthorizationCod
 		if (ClientAuthenticationMethod.POST.equals(clientRegistration.getClientAuthenticationMethod())) {
 			formParameters.add(OAuth2ParameterNames.CLIENT_SECRET, clientRegistration.getClientSecret());
 		}
-		if(ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())){
+		if (ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())){
 			formParameters.add(ClientAssertionParameterNames.CLIENT_ASSERTION_TYPE, ClientAssertionParameterValues.CLIENT_ASSERTION_TYPE_JWT_BEARER);
 			formParameters.add(ClientAssertionParameterNames.CLIENT_ASSERTION, OAuth2AuthorizationGrantRequestEntityUtils.getClientSecretAssertion(clientRegistration).serialize());
 		}
diff --git a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationGrantRequestEntityUtils.java b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationGrantRequestEntityUtils.java
index f2255a487cb..ee846382cf3 100644
--- a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationGrantRequestEntityUtils.java
+++ b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationGrantRequestEntityUtils.java
@@ -77,7 +77,7 @@ static JWT getClientSecretAssertion(ClientRegistration clientRegistration){
 
 		JWT clientAssertion = null;
 
-		if(ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())) {
+		if (ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())) {
 
 			try {
 				ClientID clientID = new ClientID(clientRegistration.getClientId());
@@ -92,13 +92,13 @@ static JWT getClientSecretAssertion(ClientRegistration clientRegistration){
 						, secret).getClientAssertion();
 			} catch (JOSEException e) {
 				OAuth2Error oauth2Error = new OAuth2Error("Client_secret_jwt",
-						"Encountered an error generating a client secret JWT",null);
-				throw new OAuth2AuthenticationException(oauth2Error,e.getMessage());
+						"Encountered an error generating a client secret JWT", null);
+				throw new OAuth2AuthenticationException(oauth2Error, e.getMessage());
 
 			} catch(URISyntaxException e){
 				OAuth2Error oauth2Error = new OAuth2Error("token_endpoint",
-						"The token endpoint provided or configured doesn't conform to a standard URI Pattern",null);
-				throw new OAuth2AuthenticationException(oauth2Error,e.getMessage());
+						"The token endpoint provided or configured doesn't conform to a standard URI Pattern", null);
+				throw new OAuth2AuthenticationException(oauth2Error, e.getMessage());
 			}
 		}
 
diff --git a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2ClientCredentialsGrantRequestEntityConverter.java b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2ClientCredentialsGrantRequestEntityConverter.java
index 762184a5354..6c8de06c8bd 100644
--- a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2ClientCredentialsGrantRequestEntityConverter.java
+++ b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2ClientCredentialsGrantRequestEntityConverter.java
@@ -83,7 +83,7 @@ private MultiValueMap<String, String> buildFormParameters(OAuth2ClientCredential
 			formParameters.add(OAuth2ParameterNames.CLIENT_ID, clientRegistration.getClientId());
 			formParameters.add(OAuth2ParameterNames.CLIENT_SECRET, clientRegistration.getClientSecret());
 		}
-		if(ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())){
+		if (ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())){
 			formParameters.add(ClientAssertionParameterNames.CLIENT_ASSERTION_TYPE, ClientAssertionParameterValues.CLIENT_ASSERTION_TYPE_JWT_BEARER);
 			formParameters.add(ClientAssertionParameterNames.CLIENT_ASSERTION, OAuth2AuthorizationGrantRequestEntityUtils.getClientSecretAssertion(clientRegistration).serialize());
 		}
diff --git a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2PasswordGrantRequestEntityConverter.java b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2PasswordGrantRequestEntityConverter.java
index 91b174e6bd4..3c1bdc2b23f 100644
--- a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2PasswordGrantRequestEntityConverter.java
+++ b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2PasswordGrantRequestEntityConverter.java
@@ -85,7 +85,7 @@ private MultiValueMap<String, String> buildFormParameters(OAuth2PasswordGrantReq
 			formParameters.add(OAuth2ParameterNames.CLIENT_ID, clientRegistration.getClientId());
 			formParameters.add(OAuth2ParameterNames.CLIENT_SECRET, clientRegistration.getClientSecret());
 		}
-		if(ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())){
+		if (ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())){
 			formParameters.add(ClientAssertionParameterNames.CLIENT_ASSERTION_TYPE, ClientAssertionParameterValues.CLIENT_ASSERTION_TYPE_JWT_BEARER);
 			formParameters.add(ClientAssertionParameterNames.CLIENT_ASSERTION, OAuth2AuthorizationGrantRequestEntityUtils.getClientSecretAssertion(clientRegistration).serialize());
 		}
diff --git a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2RefreshTokenGrantRequestEntityConverter.java b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2RefreshTokenGrantRequestEntityConverter.java
index 4f460313cf1..7357e2e6b73 100644
--- a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2RefreshTokenGrantRequestEntityConverter.java
+++ b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/endpoint/OAuth2RefreshTokenGrantRequestEntityConverter.java
@@ -85,7 +85,7 @@ private MultiValueMap<String, String> buildFormParameters(OAuth2RefreshTokenGran
 			formParameters.add(OAuth2ParameterNames.CLIENT_ID, clientRegistration.getClientId());
 			formParameters.add(OAuth2ParameterNames.CLIENT_SECRET, clientRegistration.getClientSecret());
 		}
-		if(ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())){
+		if (ClientAuthenticationMethod.SECRET_JWT.equals(clientRegistration.getClientAuthenticationMethod())){
 			formParameters.add(ClientAssertionParameterNames.CLIENT_ASSERTION_TYPE, ClientAssertionParameterValues.CLIENT_ASSERTION_TYPE_JWT_BEARER);
 			formParameters.add(ClientAssertionParameterNames.CLIENT_ASSERTION, OAuth2AuthorizationGrantRequestEntityUtils.getClientSecretAssertion(clientRegistration).serialize());
 		}
diff --git a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/jackson2/StdConverters.java b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/jackson2/StdConverters.java
index 37b9f7ba916..36ca915a132 100644
--- a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/jackson2/StdConverters.java
+++ b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/jackson2/StdConverters.java
@@ -50,8 +50,8 @@ public ClientAuthenticationMethod convert(JsonNode jsonNode) {
 			if (ClientAuthenticationMethod.BASIC.getValue().equalsIgnoreCase(value)) {
 				return ClientAuthenticationMethod.BASIC;
 			} else if (ClientAuthenticationMethod.POST.getValue().equalsIgnoreCase(value)) {
-				return ClientAuthenticationMethod.POST;}
-			else if (ClientAuthenticationMethod.SECRET_JWT.getValue().equalsIgnoreCase(value)) {
+				return ClientAuthenticationMethod.POST;
+			} else if (ClientAuthenticationMethod.SECRET_JWT.getValue().equalsIgnoreCase(value)) {
 				return ClientAuthenticationMethod.SECRET_JWT;
 			} else if (ClientAuthenticationMethod.NONE.getValue().equalsIgnoreCase(value)) {
 				return ClientAuthenticationMethod.NONE;
diff --git a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/registration/ClientRegistration.java b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/registration/ClientRegistration.java
index 6e0d6126a27..4a171e64937 100644
--- a/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/registration/ClientRegistration.java
+++ b/oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/registration/ClientRegistration.java
@@ -15,7 +15,6 @@
  */
 package org.springframework.security.oauth2.client.registration;
 
-import com.nimbusds.jose.JWSAlgorithm;
 import java.io.Serializable;
 import java.util.Arrays;
 import java.util.Collection;
diff --git a/oauth2/oauth2-client/src/test/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationCodeGrantRequestEntityConverterTests.java b/oauth2/oauth2-client/src/test/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationCodeGrantRequestEntityConverterTests.java
index dd415003440..b42dcd1c0e4 100644
--- a/oauth2/oauth2-client/src/test/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationCodeGrantRequestEntityConverterTests.java
+++ b/oauth2/oauth2-client/src/test/java/org/springframework/security/oauth2/client/endpoint/OAuth2AuthorizationCodeGrantRequestEntityConverterTests.java
@@ -34,7 +34,6 @@
 import org.springframework.security.oauth2.core.endpoint.OAuth2AuthorizationResponse;
 import org.springframework.security.oauth2.core.endpoint.OAuth2ParameterNames;
 import org.springframework.security.oauth2.core.endpoint.PkceParameterNames;
-import org.springframework.security.oauth2.jose.jws.JwsAlgorithms;
 import org.springframework.util.MultiValueMap;
 
 import java.util.Arrays;
@@ -44,7 +43,6 @@
 import java.util.Date;
 
 import static org.assertj.core.api.Assertions.assertThat;
-import static org.junit.Assert.assertTrue;
 import static org.springframework.http.MediaType.APPLICATION_FORM_URLENCODED_VALUE;
 
 /**
@@ -199,7 +197,7 @@ public void convertWhenGrantRequestValidThenConverts() {
 				.isEqualTo(ClientAssertionParameterValues.CLIENT_ASSERTION_TYPE_JWT_BEARER);
 		assertThat(formParameters.getFirst(ClientAssertionParameterNames.CLIENT_ASSERTION))
 				.isNotEmpty();
-		assertTrue(validateJWTSecret(formParameters.getFirst(ClientAssertionParameterNames.CLIENT_ASSERTION),clientRegistration));
+		assertThat(validateJWTSecret(formParameters.getFirst(ClientAssertionParameterNames.CLIENT_ASSERTION), clientRegistration)).isTrue();
 
 	}
 
@@ -240,7 +238,7 @@ public void convertWhenGrantRequestInValidSecretLengthThenConvertFails() {
 		RequestEntity<?> requestEntity = this.converter.convert(authorizationCodeGrantRequest);
 	}
 
-	private boolean validateJWTSecret(String jwt,ClientRegistration registration ){
+	private boolean validateJWTSecret(String jwt, ClientRegistration registration ){
 
 		boolean success;
 
diff --git a/oauth2/oauth2-core/src/main/java/org/springframework/security/oauth2/core/endpoint/ClientAssertionParameterNames.java b/oauth2/oauth2-core/src/main/java/org/springframework/security/oauth2/core/endpoint/ClientAssertionParameterNames.java
index 7a6f85e771c..9d1dca8cb6c 100644
--- a/oauth2/oauth2-core/src/main/java/org/springframework/security/oauth2/core/endpoint/ClientAssertionParameterNames.java
+++ b/oauth2/oauth2-core/src/main/java/org/springframework/security/oauth2/core/endpoint/ClientAssertionParameterNames.java
@@ -1,20 +1,17 @@
 /*
+ * Copyright 2002-2019 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
  *
- *  * Copyright 2020 Paychex, Inc.
- *  *
- *  * 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.
+ *      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.
  */
 
 package org.springframework.security.oauth2.core.endpoint;
diff --git a/oauth2/oauth2-core/src/main/java/org/springframework/security/oauth2/core/endpoint/ClientAssertionParameterValues.java b/oauth2/oauth2-core/src/main/java/org/springframework/security/oauth2/core/endpoint/ClientAssertionParameterValues.java
index 7ad7fad13a2..4197c08bc1f 100644
--- a/oauth2/oauth2-core/src/main/java/org/springframework/security/oauth2/core/endpoint/ClientAssertionParameterValues.java
+++ b/oauth2/oauth2-core/src/main/java/org/springframework/security/oauth2/core/endpoint/ClientAssertionParameterValues.java
@@ -1,20 +1,17 @@
 /*
+ * Copyright 2002-2019 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
  *
- *  * Copyright 2020 Paychex, Inc.
- *  *
- *  * 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.
+ *      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.
  */
 
 package org.springframework.security.oauth2.core.endpoint;