Extract Converter from AuthorizationResponseMatcher

Fixes gh-4653

oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/web/AuthorizationCodeAuthenticationFilter.java

@@ -105,7 +105,7 @@ public class AuthorizationCodeAuthenticationFilter extends AbstractAuthenticatio
 		}
 		this.authorizationRequestRepository.removeAuthorizationRequest(request);
 
-		AuthorizationResponse authorizationResponse = this.authorizationResponseMatcher.convert(request);
+		AuthorizationResponse authorizationResponse = this.convert(request);
 
 		String registrationId = (String)authorizationRequest.getAdditionalParameters().get(OAuth2Parameter.REGISTRATION_ID);
 		ClientRegistration clientRegistration = this.clientRegistrationRepository.findByRegistrationId(registrationId);
@@ -151,6 +151,33 @@ public class AuthorizationCodeAuthenticationFilter extends AbstractAuthenticatio
 		this.authorizationRequestRepository = authorizationRequestRepository;
 	}
 
+	private AuthorizationResponse convert(HttpServletRequest request) {
+		if (!this.getAuthorizationResponseMatcher().matches(request)) {
+			return null;
+		}
+
+		String code = request.getParameter(OAuth2Parameter.CODE);
+		String errorCode = request.getParameter(OAuth2Parameter.ERROR);
+		String state = request.getParameter(OAuth2Parameter.STATE);
+		String redirectUri = request.getRequestURL().toString();
+
+		if (StringUtils.hasText(code)) {
+			return AuthorizationResponse.success(code)
+				.redirectUri(redirectUri)
+				.state(state)
+				.build();
+		} else {
+			String errorDescription = request.getParameter(OAuth2Parameter.ERROR_DESCRIPTION);
+			String errorUri = request.getParameter(OAuth2Parameter.ERROR_URI);
+			return AuthorizationResponse.error(errorCode)
+				.redirectUri(redirectUri)
+				.errorDescription(errorDescription)
+				.errorUri(errorUri)
+				.state(state)
+				.build();
+		}
+	}
+
 	private static class AuthorizationResponseMatcher implements RequestMatcher {
 		private final String baseUri;
 
@@ -174,32 +201,5 @@ public class AuthorizationCodeAuthenticationFilter extends AbstractAuthenticatio
 			return StringUtils.hasText(request.getParameter(OAuth2Parameter.ERROR)) &&
 				StringUtils.hasText(request.getParameter(OAuth2Parameter.STATE));
 		}
-
-		private AuthorizationResponse convert(HttpServletRequest request) {
-			if (!this.matches(request)) {
-				return null;
-			}
-
-			String code = request.getParameter(OAuth2Parameter.CODE);
-			String errorCode = request.getParameter(OAuth2Parameter.ERROR);
-			String state = request.getParameter(OAuth2Parameter.STATE);
-			String redirectUri = request.getRequestURL().toString();
-
-			if (StringUtils.hasText(code)) {
-				return AuthorizationResponse.success(code)
-					.redirectUri(redirectUri)
-					.state(state)
-					.build();
-			} else {
-				String errorDescription = request.getParameter(OAuth2Parameter.ERROR_DESCRIPTION);
-				String errorUri = request.getParameter(OAuth2Parameter.ERROR_URI);
-				return AuthorizationResponse.error(errorCode)
-					.redirectUri(redirectUri)
-					.errorDescription(errorDescription)
-					.errorUri(errorUri)
-					.state(state)
-					.build();
-			}
-		}
 	}
 }