diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/CosysAdapter.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/CosysAdapter.java
index aeb070e1..95e8d4b3 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/CosysAdapter.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/CosysAdapter.java
@@ -18,6 +18,7 @@ public class CosysAdapter implements GenerateDocumentOutPort {
 
     public static final String DATA_FILE_NAME = "data";
     public static final String MERGE_FILE_NAME = "merge";
+    public static final String DOC_GEN_EXCEPTION_MESSAGE = "Document could not be created.";
 
     private final CosysConfiguration configuration;
     private final GenerationApi generationApi;
@@ -47,15 +48,15 @@ public Mono<byte[]> generateCosysDocument(final GenerateDocument generateDocumen
                     null)
                     .onStatus(HttpStatusCode::is5xxServerError,
                             response -> response.bodyToMono(byte[].class)
-                                    .flatMap(body -> Mono.error(new CosysException("Document could not be created."))))
+                                    .flatMap(body -> Mono.error(new CosysException(DOC_GEN_EXCEPTION_MESSAGE))))
                     .onStatus(HttpStatusCode::is4xxClientError,
                             response -> response.bodyToMono(byte[].class)
-                                    .flatMap(body -> Mono.error(new CosysException("Document could not be created."))))
+                                    .flatMap(body -> Mono.error(new CosysException(DOC_GEN_EXCEPTION_MESSAGE))))
                     .bodyToMono(byte[].class);
 
         } catch (final IOException ex) {
-            log.error("Document could not be created.", ex);
-            throw new CosysException("Document could not be created.");
+            log.error(DOC_GEN_EXCEPTION_MESSAGE, ex);
+            throw new CosysException(DOC_GEN_EXCEPTION_MESSAGE, ex);
         }
     }
 
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/FileUtils.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/FileUtils.java
index adac24da..566a4f76 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/FileUtils.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/FileUtils.java
@@ -5,7 +5,9 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 
-public class FileUtils {
+public final class FileUtils {
+    private FileUtils() {
+    }
 
     public static File createFile(final String name, final byte[] content) throws IOException {
         final Path tempFile = Files.createTempFile(name, ".json");
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/s3/S3Adapter.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/s3/S3Adapter.java
index c67d82e0..3a1ffdb6 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/s3/S3Adapter.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/adapter/out/s3/S3Adapter.java
@@ -34,9 +34,10 @@ public void saveDocumentInStorage(
     }
 
     private void validateFileSize(final byte[] data) {
-        if (!fileValidationService.isValidFileSize(data))
+        if (!fileValidationService.isValidFileSize(data)) {
             throw new FileSizeValidationException(
                     String.format("Invalid file size %d MB. Allowed are %d MB.", DataSize.ofBytes(data.length).toMegabytes(),
                             fileValidationService.getMaxFileSize().toMegabytes()));
+        }
     }
 }
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/in/CreateDocumentInPort.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/in/CreateDocumentInPort.java
index 5e2a48fa..faaadbeb 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/in/CreateDocumentInPort.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/in/CreateDocumentInPort.java
@@ -9,6 +9,6 @@
 public interface CreateDocumentInPort {
 
     void createDocument(
-            @Valid final GenerateDocument generateDocument,
-            @NotBlank final String filePath) throws CosysException, DocumentStorageException;
+            @Valid GenerateDocument generateDocument,
+            @NotBlank String filePath) throws CosysException, DocumentStorageException;
 }
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/out/GenerateDocumentOutPort.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/out/GenerateDocumentOutPort.java
index 7aa6feb0..5fab2d13 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/out/GenerateDocumentOutPort.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/out/GenerateDocumentOutPort.java
@@ -6,6 +6,6 @@
 
 public interface GenerateDocumentOutPort {
 
-    Mono<byte[]> generateCosysDocument(final GenerateDocument generateDocument) throws CosysException;
+    Mono<byte[]> generateCosysDocument(GenerateDocument generateDocument) throws CosysException;
 
 }
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/out/SaveFileToStorageOutPort.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/out/SaveFileToStorageOutPort.java
index 3f38eb9d..d17cc71d 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/out/SaveFileToStorageOutPort.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/application/port/out/SaveFileToStorageOutPort.java
@@ -4,6 +4,6 @@
 
 public interface SaveFileToStorageOutPort {
     void saveDocumentInStorage(
-            final String filePath,
-            final byte[] data) throws DocumentStorageException;
+            String filePath,
+            byte[] data) throws DocumentStorageException;
 }
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/domain/exception/CosysException.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/domain/exception/CosysException.java
index 59a93cb8..4e083e40 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/domain/exception/CosysException.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/main/java/de/muenchen/refarch/integration/cosys/domain/exception/CosysException.java
@@ -1,7 +1,12 @@
 package de.muenchen.refarch.integration.cosys.domain.exception;
 
+@SuppressWarnings("PMD.MissingSerialVersionUID")
 public class CosysException extends Exception {
     public CosysException(final String message) {
         super(message);
     }
+
+    public CosysException(final String message, final Throwable cause) {
+        super(message, cause);
+    }
 }
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/CosysAdapterTest.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/CosysAdapterTest.java
index 5c9d8d7d..54ff9e46 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/CosysAdapterTest.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/adapter/out/cosys/CosysAdapterTest.java
@@ -12,7 +12,6 @@
 import de.muenchen.refarch.integration.cosys.domain.model.GenerateDocument;
 import java.io.File;
 import java.io.IOException;
-import lombok.val;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.ArgumentCaptor;
@@ -40,11 +39,11 @@ void setUp() {
     }
 
     @Test
-    void testGenerateCosysDocument_Success() throws IOException, CosysException {
+    void testGenerateCosysDocumentSuccess() throws IOException, CosysException {
         // given
-        val generateDocument = generateDocument();
-        val response = "Response".getBytes();
-        val responseSpecMock = Mockito.mock(WebClient.ResponseSpec.class);
+        final GenerateDocument generateDocument = generateDocument();
+        final byte[] response = "Response".getBytes();
+        final WebClient.ResponseSpec responseSpecMock = Mockito.mock(WebClient.ResponseSpec.class);
         when(responseSpecMock.onStatus(any(), any())).thenReturn(responseSpecMock);
         when(responseSpecMock.bodyToMono(byte[].class)).thenReturn(Mono.just(response));
         final ArgumentCaptor<File> dataFileCaptor = ArgumentCaptor.forClass(File.class);
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/adapter/out/s3/S3AdapterTest.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/adapter/out/s3/S3AdapterTest.java
index a5c52fe7..af079c6d 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/adapter/out/s3/S3AdapterTest.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/adapter/out/s3/S3AdapterTest.java
@@ -52,18 +52,18 @@ void saveDocumentInStorageWithThrowsDocumentStorageException()
             throws DocumentStorageException, DocumentStorageClientErrorException, DocumentStorageServerErrorException {
         doThrow(new DocumentStorageException("DocumentStorageClientErrorException", new Exception())).when(documentStorageFileRepository)
                 .saveFile(anyString(), any(), eq(1));
-        DocumentStorageException documentStorageException = assertThrows(DocumentStorageException.class,
+        final DocumentStorageException documentStorageException = assertThrows(DocumentStorageException.class,
                 () -> s3Adapter.saveDocumentInStorage("filePath.txt", DATA_AS_BYTE_ARRAY));
 
-        String expectedMessage = "Document could not be saved.";
-        String actualMessage = documentStorageException.getMessage();
+        final String expectedMessage = "Document could not be saved.";
+        final String actualMessage = documentStorageException.getMessage();
 
         assertEquals(expectedMessage, actualMessage);
     }
 
     @Test
     void testSaveDocumentInStorageThrowsBpmnErrorForInvalidFileSize() {
-        String expectedMessage = String.format("Invalid file size %d MB. Allowed are %d MB.", DataSize.ofBytes(TOO_LARGE_FILE.length).toMegabytes(),
+        final String expectedMessage = String.format("Invalid file size %d MB. Allowed are %d MB.", DataSize.ofBytes(TOO_LARGE_FILE.length).toMegabytes(),
                 ALLOWED_FILE_SIZE.toMegabytes());
 
         assertThatThrownBy(() -> s3Adapter.saveDocumentInStorage("filePath.txt", TOO_LARGE_FILE))
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/application/usecase/CreateDocumentUseCaseTest.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/application/usecase/CreateDocumentUseCaseTest.java
index 9e57fdfd..73d2db05 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/application/usecase/CreateDocumentUseCaseTest.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-core/src/test/java/de/muenchen/refarch/integration/cosys/application/usecase/CreateDocumentUseCaseTest.java
@@ -24,7 +24,7 @@ class CreateDocumentUseCaseTest {
 
     private final GenerateDocument generateDocument = new GenerateDocument("Client", "Role", "guid", new ObjectMapper().readTree("{\"key1\":\"value\"}"));
 
-    CreateDocumentUseCaseTest() throws JsonProcessingException {
+    protected CreateDocumentUseCaseTest() throws JsonProcessingException {
     }
 
     @Test
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/CosysExampleApplication.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/CosysExampleApplication.java
index 040470d6..19fa1351 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/CosysExampleApplication.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/CosysExampleApplication.java
@@ -4,6 +4,7 @@
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 
 @SpringBootApplication()
+@SuppressWarnings("PMD.UseUtilityClass")
 public class CosysExampleApplication {
 
     public static void main(final String[] args) {
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/NoSecurityConfiguration.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/NoSecurityConfiguration.java
index 25792181..1c7712b1 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/NoSecurityConfiguration.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/NoSecurityConfiguration.java
@@ -13,7 +13,7 @@
 public class NoSecurityConfiguration {
 
     @Bean
-    public SecurityFilterChain mainSecurityFilterChain(HttpSecurity http) throws Exception {
+    public SecurityFilterChain mainSecurityFilterChain(final HttpSecurity http) throws Exception {
         // @formatter:off
         http
                 .headers(httpSecurityHeadersConfigurer -> httpSecurityHeadersConfigurer.frameOptions(HeadersConfigurer.FrameOptionsConfig::disable))
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/api/controller/ExampleController.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/api/controller/ExampleController.java
index 4aad7899..92d82b46 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/api/controller/ExampleController.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-example/src/main/java/de/muenchen/refarch/integration/cosys/example/api/controller/ExampleController.java
@@ -18,7 +18,7 @@ public class ExampleController {
 
     private final GenerateDocumentOutPort generateDocumentOutPort;
 
-    @PostMapping(value = "/test/document")
+    @PostMapping("/test/document")
     public ResponseEntity<byte[]> testCreateCosysDocument() throws CosysException {
         final byte[] file = this.generateDocumentOutPort.generateCosysDocument(this.generateDocument()).block();
         return ResponseEntity.ok(file);
diff --git a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-starter/src/main/java/de/muenchen/refarch/integration/cosys/configuration/CosysAutoConfiguration.java b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-starter/src/main/java/de/muenchen/refarch/integration/cosys/configuration/CosysAutoConfiguration.java
index 7508d612..8feee2e1 100644
--- a/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-starter/src/main/java/de/muenchen/refarch/integration/cosys/configuration/CosysAutoConfiguration.java
+++ b/refarch-integrations/refarch-cosys-integration/refarch-cosys-integration-starter/src/main/java/de/muenchen/refarch/integration/cosys/configuration/CosysAutoConfiguration.java
@@ -71,7 +71,7 @@ public ApiClient cosysApiClient(final ClientRegistrationRepository clientRegistr
     private WebClient webClient(
             final ClientRegistrationRepository clientRegistrationRepository,
             final OAuth2AuthorizedClientService authorizedClientService) {
-        final var oauth = new ServletOAuth2AuthorizedClientExchangeFilterFunction(
+        final ServletOAuth2AuthorizedClientExchangeFilterFunction oauth = new ServletOAuth2AuthorizedClientExchangeFilterFunction(
                 new AuthorizedClientServiceOAuth2AuthorizedClientManager(
                         clientRegistrationRepository, authorizedClientService));
         oauth.setDefaultClientRegistrationId("cosys");