Refactor Spring Data examples

spring-data-rest/src/main/java/com/baeldung/config/ValidatorEventRegister.java

@@ -22,9 +22,15 @@ public class ValidatorEventRegister implements InitializingBean {
     @Override
     public void afterPropertiesSet() throws Exception {
         List<String> events = Arrays.asList("beforeCreate", "afterCreate", "beforeSave", "afterSave", "beforeLinkSave", "afterLinkSave", "beforeDelete", "afterDelete");
-        
+
         for (Map.Entry<String, Validator> entry : validators.entrySet()) {
-            events.stream().filter(p -> entry.getKey().startsWith(p)).findFirst().ifPresent(p -> validatingRepositoryEventListener.addValidator(p, entry.getValue()));
+            events
+              .stream()
+              .filter(p -> entry
+                .getKey()
+                .startsWith(p))
+              .findFirst()
+              .ifPresent(p -> validatingRepositoryEventListener.addValidator(p, entry.getValue()));
         }
     }
 }

spring-data-rest/src/main/java/com/baeldung/exception/handlers/RestResponseEntityExceptionHandler.java

@@ -1,16 +1,17 @@
 package com.baeldung.exception.handlers;
 
-import java.util.stream.Collectors;
-
 import org.springframework.data.rest.core.RepositoryConstraintViolationException;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
+import org.springframework.validation.ObjectError;
 import org.springframework.web.bind.annotation.ControllerAdvice;
 import org.springframework.web.bind.annotation.ExceptionHandler;
 import org.springframework.web.context.request.WebRequest;
 import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;
 
+import java.util.stream.Collectors;
+
 @ControllerAdvice
 public class RestResponseEntityExceptionHandler extends ResponseEntityExceptionHandler {
 
@@ -18,8 +19,13 @@ public class RestResponseEntityExceptionHandler extends ResponseEntityExceptionH
     public ResponseEntity<Object> handleAccessDeniedException(Exception ex, WebRequest request) {
         RepositoryConstraintViolationException nevEx = (RepositoryConstraintViolationException) ex;
 
-        String errors = nevEx.getErrors().getAllErrors().stream().map(p -> p.toString()).collect(Collectors.joining("\n"));
-        return new ResponseEntity<Object>(errors, new HttpHeaders(), HttpStatus.NOT_ACCEPTABLE);
+        String errors = nevEx
+          .getErrors()
+          .getAllErrors()
+          .stream()
+          .map(ObjectError::toString)
+          .collect(Collectors.joining("\n"));
+        return new ResponseEntity<>(errors, new HttpHeaders(), HttpStatus.NOT_ACCEPTABLE);
     }
 
 }