diff --git a/spring-data-mongodb/src/main/java/org/baeldung/config/MongoConfig.java b/spring-data-mongodb/src/main/java/org/baeldung/config/MongoConfig.java
index 4b776af5b6..8fbe966074 100644
--- a/spring-data-mongodb/src/main/java/org/baeldung/config/MongoConfig.java
+++ b/spring-data-mongodb/src/main/java/org/baeldung/config/MongoConfig.java
@@ -7,9 +7,9 @@ import org.baeldung.converter.UserWriterConverter;
 import org.baeldung.event.CascadeSaveMongoEventListener;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
+import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.mongodb.config.AbstractMongoConfiguration;
 import org.springframework.data.mongodb.core.convert.CustomConversions;
-import org.springframework.core.convert.converter.Converter;
 import org.springframework.data.mongodb.repository.config.EnableMongoRepositories;
 
 import com.mongodb.Mongo;
@@ -19,7 +19,7 @@ import com.mongodb.MongoClient;
 @EnableMongoRepositories(basePackages = "org.baeldung.repository")
 public class MongoConfig extends AbstractMongoConfiguration {
 
-    private List<Converter<?, ?>> converters = new ArrayList<Converter<?, ?>>();
+    private final List<Converter<?, ?>> converters = new ArrayList<Converter<?, ?>>();
 
     @Override
     protected String getDatabaseName() {
diff --git a/spring-data-mongodb/src/main/java/org/baeldung/converter/UserWriterConverter.java b/spring-data-mongodb/src/main/java/org/baeldung/converter/UserWriterConverter.java
index 18f2314c6b..54fa78e2d0 100644
--- a/spring-data-mongodb/src/main/java/org/baeldung/converter/UserWriterConverter.java
+++ b/spring-data-mongodb/src/main/java/org/baeldung/converter/UserWriterConverter.java
@@ -1,8 +1,8 @@
 package org.baeldung.converter;
 
-import org.springframework.stereotype.Component;
 import org.baeldung.model.User;
 import org.springframework.core.convert.converter.Converter;
+import org.springframework.stereotype.Component;
 
 import com.mongodb.BasicDBObject;
 import com.mongodb.DBObject;
@@ -10,12 +10,12 @@ import com.mongodb.DBObject;
 @Component
 public class UserWriterConverter implements Converter<User, DBObject> {
     @Override
-    public DBObject convert(User user) {
-        DBObject dbObject = new BasicDBObject();
+    public DBObject convert(final User user) {
+        final DBObject dbObject = new BasicDBObject();
         dbObject.put("name", user.getName());
         dbObject.put("age", user.getAge());
         if (user.getEmailAddress() != null) {
-            DBObject emailDbObject = new BasicDBObject();
+            final DBObject emailDbObject = new BasicDBObject();
             emailDbObject.put("value", user.getEmailAddress().getValue());
             dbObject.put("email", emailDbObject);
         }
diff --git a/spring-data-mongodb/src/main/java/org/baeldung/event/CascadeCallback.java b/spring-data-mongodb/src/main/java/org/baeldung/event/CascadeCallback.java
index e56caad4cb..e01a1bc8c0 100644
--- a/spring-data-mongodb/src/main/java/org/baeldung/event/CascadeCallback.java
+++ b/spring-data-mongodb/src/main/java/org/baeldung/event/CascadeCallback.java
@@ -18,14 +18,14 @@ public class CascadeCallback implements ReflectionUtils.FieldCallback {
     }
 
     @Override
-    public void doWith(Field field) throws IllegalArgumentException, IllegalAccessException {
+    public void doWith(final Field field) throws IllegalArgumentException, IllegalAccessException {
         ReflectionUtils.makeAccessible(field);
 
         if (field.isAnnotationPresent(DBRef.class) && field.isAnnotationPresent(CascadeSave.class)) {
             final Object fieldValue = field.get(getSource());
 
             if (fieldValue != null) {
-                FieldCallback callback = new FieldCallback();
+                final FieldCallback callback = new FieldCallback();
 
                 ReflectionUtils.doWithFields(fieldValue.getClass(), callback);
 
@@ -39,7 +39,7 @@ public class CascadeCallback implements ReflectionUtils.FieldCallback {
         return source;
     }
 
-    public void setSource(Object source) {
+    public void setSource(final Object source) {
         this.source = source;
     }
 
@@ -47,7 +47,7 @@ public class CascadeCallback implements ReflectionUtils.FieldCallback {
         return mongoOperations;
     }
 
-    public void setMongoOperations(MongoOperations mongoOperations) {
+    public void setMongoOperations(final MongoOperations mongoOperations) {
         this.mongoOperations = mongoOperations;
     }
 }
diff --git a/spring-data-mongodb/src/main/java/org/baeldung/event/FieldCallback.java b/spring-data-mongodb/src/main/java/org/baeldung/event/FieldCallback.java
index 868bbc31f0..c6bd90d4f3 100644
--- a/spring-data-mongodb/src/main/java/org/baeldung/event/FieldCallback.java
+++ b/spring-data-mongodb/src/main/java/org/baeldung/event/FieldCallback.java
@@ -8,7 +8,8 @@ import org.springframework.util.ReflectionUtils;
 public class FieldCallback implements ReflectionUtils.FieldCallback {
     private boolean idFound;
 
-    public void doWith(Field field) throws IllegalArgumentException, IllegalAccessException {
+    @Override
+    public void doWith(final Field field) throws IllegalArgumentException, IllegalAccessException {
         ReflectionUtils.makeAccessible(field);
 
         if (field.isAnnotationPresent(Id.class)) {
diff --git a/spring-data-mongodb/src/main/java/org/baeldung/model/User.java b/spring-data-mongodb/src/main/java/org/baeldung/model/User.java
index 64fe404f5e..b67d632780 100644
--- a/spring-data-mongodb/src/main/java/org/baeldung/model/User.java
+++ b/spring-data-mongodb/src/main/java/org/baeldung/model/User.java
@@ -73,7 +73,7 @@ public class User {
         return emailAddress;
     }
 
-    public void setEmailAddress(EmailAddress emailAddress) {
+    public void setEmailAddress(final EmailAddress emailAddress) {
         this.emailAddress = emailAddress;
     }
 
@@ -81,7 +81,7 @@ public class User {
         return yearOfBirth;
     }
 
-    public void setYearOfBirth(Integer yearOfBirth) {
+    public void setYearOfBirth(final Integer yearOfBirth) {
         this.yearOfBirth = yearOfBirth;
     }
 
diff --git a/spring-data-mongodb/src/main/java/org/baeldung/repository/UserRepository.java b/spring-data-mongodb/src/main/java/org/baeldung/repository/UserRepository.java
index 72d9a4dba0..28b21ffb43 100644
--- a/spring-data-mongodb/src/main/java/org/baeldung/repository/UserRepository.java
+++ b/spring-data-mongodb/src/main/java/org/baeldung/repository/UserRepository.java
@@ -3,7 +3,6 @@ package org.baeldung.repository;
 import java.util.List;
 
 import org.baeldung.model.User;
-
 import org.springframework.data.mongodb.repository.MongoRepository;
 import org.springframework.data.mongodb.repository.Query;
 import org.springframework.data.querydsl.QueryDslPredicateExecutor;