diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000000000000000000000000000000000000..4b7873897c7401b1ae3ab45c2bdff3ea54642c2f
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,4 @@
+*iml
+.idea/
+target/
+master_key.txt
diff --git a/LICENSE b/LICENSE
new file mode 100644
index 0000000000000000000000000000000000000000..261eeb9e9f8b2b4b0d119366dda99c6fd7d35c64
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1,201 @@
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diff --git a/README.md b/README.md
new file mode 100644
index 0000000000000000000000000000000000000000..3f8b305f153d141f2c3e59bdc8940551c29d8c25
--- /dev/null
+++ b/README.md
@@ -0,0 +1,110 @@
+# Java Quick Start Project
+
+This repository contains code samples for the Quick Start blog post series.
+
+You can read more about the Quick Start series on the [MongoDB Developer Hub](https://www.mongodb.com/developer/).
+
+- [MongoDB & Java - CRUD Operations Tutorial](https://www.mongodb.com/developer/languages/java/java-setup-crud-operations/)
+- [Java - Mapping POJOs](https://www.mongodb.com/developer/languages/java/java-mapping-pojos/)
+- [Java - Aggregation Pipeline](https://www.mongodb.com/developer/languages/java/java-aggregation-pipeline/)
+- [Java - Change Streams](https://www.mongodb.com/developer/languages/java/java-change-streams/)
+- [Java - Client Side Field Level Encryption](https://www.mongodb.com/developer/languages/java/java-client-side-field-level-encryption/)
+- [Java - Multi-Doc ACID Transactions](https://www.mongodb.com/developer/languages/java/java-multi-doc-acid-transactions/)
+
+# MongoDB Cluster
+
+To get started with MongoDB Atlas and get a free cluster read [this blog post](https://developer.mongodb.com/quickstart/free-atlas-cluster).
+
+# Requirements
+
+- Java 21
+- Maven 3.8.7.
+
+# Command lines
+
+- Compile: 
+
+```sh
+mvn clean compile
+```
+
+- Run the `HelloMongoDB` class: 
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.HelloMongoDB"
+```
+- Run the `Connection` class: 
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.Connection" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+- Run the `Create` class:
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.Create" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+- Run the `Read` class:
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.Read" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+- Run the `Update` class:
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.Update" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+- Run the `Delete` class:
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.Delete" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+- Run the `MappingPOJO` class:
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.MappingPOJO" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+- Run the `AggregationFramework` class:
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.AggregationFramework" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+- Run the `ChangeStreams` class:
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.ChangeStreams" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+- Run the `ClientSideFieldLevelEncryption` class:
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.csfle.ClientSideFieldLevelEncryption" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+### Transactions
+
+Always start the `ChangeStreams` class in the `transactions` package first because it creates the `product` collection with the required JSON Schema. See the related blog post.
+
+- Run the `ChangeStreams` class:
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.transactions.ChangeStreams" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+- Run the `Transactions` class:
+
+```sh
+mvn compile exec:java -Dexec.mainClass="com.mongodb.quickstart.transactions.Transactions" -Dmongodb.uri="mongodb+srv://USERNAME:PASSWORD@cluster0-abcde.mongodb.net/test?w=majority"
+```
+
+# Author
+
+Maxime Beugnet
+- maxime@mongodb.com
+- MaBeuLux88 on [GitHub](https://github.com/mabeulux88)
+- MaBeuLux88 in the [MongoDB Developer Community forum](https://www.mongodb.com/community/forums/u/MaBeuLux88/summary).
diff --git a/pom.xml b/pom.xml
new file mode 100644
index 0000000000000000000000000000000000000000..bc21273ff72de40d1ce64736168bcb01f1be203a
--- /dev/null
+++ b/pom.xml
@@ -0,0 +1,66 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>com.mongodb</groupId>
+    <artifactId>java-quick-start</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <properties>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <maven-compiler-plugin.source>21</maven-compiler-plugin.source>
+        <maven-compiler-plugin.target>21</maven-compiler-plugin.target>
+        <maven-compiler-plugin.version>3.12.1</maven-compiler-plugin.version>
+        <mongodb-driver-sync.version>5.0.0</mongodb-driver-sync.version>
+        <mongodb-crypt.version>1.8.0</mongodb-crypt.version>
+        <!-- Keeping 1.2.13 until mongodb-crypt makes slf4j-api an optional dependency -->
+        <!-- https://jira.mongodb.org/browse/MONGOCRYPT-602 -->
+        <logback-classic.version>1.2.13</logback-classic.version>
+        <exec-maven-plugin.version>3.1.1</exec-maven-plugin.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.mongodb</groupId>
+            <artifactId>mongodb-driver-sync</artifactId>
+            <version>${mongodb-driver-sync.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.mongodb</groupId>
+            <artifactId>mongodb-crypt</artifactId>
+            <version>${mongodb-crypt.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>ch.qos.logback</groupId>
+            <artifactId>logback-classic</artifactId>
+            <version>${logback-classic.version}</version>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>${maven-compiler-plugin.version}</version>
+                <configuration>
+                    <source>${maven-compiler-plugin.source}</source>
+                    <target>${maven-compiler-plugin.target}</target>
+                </configuration>
+            </plugin>
+            <plugin>
+                <!-- Adding this plugin, so we don't need to add -Dexec.cleanupDaemonThreads=false in the mvn cmd line -->
+                <!-- to avoid the IllegalThreadStateException when running with Maven -->
+                <groupId>org.codehaus.mojo</groupId>
+                <artifactId>exec-maven-plugin</artifactId>
+                <version>${exec-maven-plugin.version}</version>
+                <configuration>
+                    <cleanupDaemonThreads>false</cleanupDaemonThreads>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+</project>
diff --git a/src/main/java/com/mongodb/quickstart/AggregationFramework.java b/src/main/java/com/mongodb/quickstart/AggregationFramework.java
new file mode 100644
index 0000000000000000000000000000000000000000..e3c9818f74a3f951734ad003d47627db3e853e7c
--- /dev/null
+++ b/src/main/java/com/mongodb/quickstart/AggregationFramework.java
@@ -0,0 +1,72 @@
+package com.mongodb.quickstart;
+
+import com.mongodb.client.MongoClient;
+import com.mongodb.client.MongoClients;
+import com.mongodb.client.MongoCollection;
+import com.mongodb.client.MongoDatabase;
+import org.bson.Document;
+import org.bson.conversions.Bson;
+import org.bson.json.JsonWriterSettings;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Consumer;
+
+import static com.mongodb.client.model.Accumulators.push;
+import static com.mongodb.client.model.Accumulators.sum;
+import static com.mongodb.client.model.Aggregates.*;
+import static com.mongodb.client.model.Filters.eq;
+import static com.mongodb.client.model.Projections.*;
+import static com.mongodb.client.model.Sorts.descending;
+
+public class AggregationFramework {
+
+    public static void main(String[] args) {
+        String connectionString = System.getProperty("mongodb.uri");
+        try (MongoClient mongoClient = MongoClients.create(connectionString)) {
+            MongoDatabase db = mongoClient.getDatabase("sample_training");
+            MongoCollection<Document> zips = db.getCollection("zips");
+            MongoCollection<Document> posts = db.getCollection("posts");
+            threeMostPopulatedCitiesInTexas(zips);
+            threeMostPopularTags(posts);
+        }
+    }
+
+    /**
+     * find the 3 most densely populated cities in Texas.
+     *
+     * @param zips sample_training.zips collection from the MongoDB Sample Dataset in MongoDB Atlas.
+     */
+    private static void threeMostPopulatedCitiesInTexas(MongoCollection<Document> zips) {
+        Bson match = match(eq("state", "TX"));
+        Bson group = group("$city", sum("totalPop", "$pop"));
+        Bson project = project(fields(excludeId(), include("totalPop"), computed("city", "$_id")));
+        Bson sort = sort(descending("totalPop"));
+        Bson limit = limit(3);
+
+        List<Document> results = zips.aggregate(List.of(match, group, project, sort, limit)).into(new ArrayList<>());
+        System.out.println("==> 3 most densely populated cities in Texas");
+        results.forEach(printDocuments());
+    }
+
+    /**
+     * find the 3 most popular tags and their post titles
+     *
+     * @param posts sample_training.posts collection from the MongoDB Sample Dataset in MongoDB Atlas.
+     */
+    private static void threeMostPopularTags(MongoCollection<Document> posts) {
+        Bson unwind = unwind("$tags");
+        Bson group = group("$tags", sum("count", 1L), push("titles", "$title"));
+        Bson sort = sort(descending("count"));
+        Bson limit = limit(3);
+        Bson project = project(fields(excludeId(), computed("tag", "$_id"), include("count", "titles")));
+
+        List<Document> results = posts.aggregate(List.of(unwind, group, sort, limit, project)).into(new ArrayList<>());
+        System.out.println("==> 3 most popular tags and their posts titles");
+        results.forEach(printDocuments());
+    }
+
+    private static Consumer<Document> printDocuments() {
+        return doc -> System.out.println(doc.toJson(JsonWriterSettings.builder().indent(true).build()));
+    }
+}
diff --git a/src/main/java/com/mongodb/quickstart/Connection.java b/src/main/java/com/mongodb/quickstart/Connection.java
new file mode 100644
index 0000000000000000000000000000000000000000..4544bd31e28fac40a308c8a387957efdeb300703
--- /dev/null
+++ b/src/main/java/com/mongodb/quickstart/Connection.java
@@ -0,0 +1,30 @@
+package com.mongodb.quickstart;
+
+import com.mongodb.client.MongoClient;
+import com.mongodb.client.MongoClients;
+import org.bson.Document;
+import org.bson.json.JsonWriterSettings;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class Connection {
+
+    public static void main(String[] args) {
+        String connectionString = System.getProperty("mongodb.uri");
+        try (MongoClient mongoClient = MongoClients.create(connectionString)) {
+            System.out.println("=> Connection successful: " + preFlightChecks(mongoClient));
+            System.out.println("=> Print list of databases:");
+            List<Document> databases = mongoClient.listDatabases().into(new ArrayList<>());
+            databases.forEach(db -> System.out.println(db.toJson()));
+        }
+    }
+
+    static boolean preFlightChecks(MongoClient mongoClient) {
+        Document pingCommand = new Document("ping", 1);
+        Document response = mongoClient.getDatabase("admin").runCommand(pingCommand);
+        System.out.println("=> Print result of the '{ping: 1}' command.");
+        System.out.println(response.toJson(JsonWriterSettings.builder().indent(true).build()));
+        return response.get("ok", Number.class).intValue() == 1;
+    }
+}
diff --git a/src/main/java/com/mongodb/quickstart/Create.java b/src/main/java/com/mongodb/quickstart/Create.java
new file mode 100644
index 0000000000000000000000000000000000000000..604ffe40ee2a66fa775db71a6f12da4852957053
--- /dev/null
+++ b/src/main/java/com/mongodb/quickstart/Create.java
@@ -0,0 +1,54 @@
+package com.mongodb.quickstart;
+
+import com.mongodb.client.MongoClient;
+import com.mongodb.client.MongoClients;
+import com.mongodb.client.MongoCollection;
+import com.mongodb.client.MongoDatabase;
+import com.mongodb.client.model.InsertManyOptions;
+import org.bson.Document;
+import org.bson.types.ObjectId;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Random;
+
+public class Create {
+
+    private static final Random rand = new Random();
+
+    public static void main(String[] args) {
+        try (MongoClient mongoClient = MongoClients.create(System.getProperty("mongodb.uri"))) {
+
+            MongoDatabase sampleTrainingDB = mongoClient.getDatabase("sample_training");
+            MongoCollection<Document> gradesCollection = sampleTrainingDB.getCollection("grades");
+
+            insertOneDocument(gradesCollection);
+            insertManyDocuments(gradesCollection);
+        }
+    }
+
+    private static void insertOneDocument(MongoCollection<Document> gradesCollection) {
+        gradesCollection.insertOne(generateNewGrade(10000d, 1d));
+        System.out.println("One grade inserted for studentId 10000.");
+    }
+
+    private static void insertManyDocuments(MongoCollection<Document> gradesCollection) {
+        List<Document> grades = new ArrayList<>();
+        for (double classId = 1d; classId <= 10d; classId++) {
+            grades.add(generateNewGrade(10001d, classId));
+        }
+
+        gradesCollection.insertMany(grades, new InsertManyOptions().ordered(false));
+        System.out.println("Ten grades inserted for studentId 10001.");
+    }
+
+    private static Document generateNewGrade(double studentId, double classId) {
+        List<Document> scores = List.of(new Document("type", "exam").append("score", rand.nextDouble() * 100),
+                                        new Document("type", "quiz").append("score", rand.nextDouble() * 100),
+                                        new Document("type", "homework").append("score", rand.nextDouble() * 100),
+                                        new Document("type", "homework").append("score", rand.nextDouble() * 100));
+        return new Document("_id", new ObjectId()).append("student_id", studentId)
+                                                  .append("class_id", classId)
+                                                  .append("scores", scores);
+    }
+}
diff --git a/src/main/java/com/mongodb/quickstart/Delete.java b/src/main/java/com/mongodb/quickstart/Delete.java
new file mode 100644
index 0000000000000000000000000000000000000000..a2a3916aa2533df24d8434d397dd153ede25b993
--- /dev/null
+++ b/src/main/java/com/mongodb/quickstart/Delete.java
@@ -0,0 +1,41 @@
+package com.mongodb.quickstart;
+
+import com.mongodb.client.MongoClient;
+import com.mongodb.client.MongoClients;
+import com.mongodb.client.MongoCollection;
+import com.mongodb.client.MongoDatabase;
+import com.mongodb.client.result.DeleteResult;
+import org.bson.Document;
+import org.bson.conversions.Bson;
+import org.bson.json.JsonWriterSettings;
+
+import static com.mongodb.client.model.Filters.eq;
+import static com.mongodb.client.model.Filters.gte;
+
+public class Delete {
+
+    public static void main(String[] args) {
+        try (MongoClient mongoClient = MongoClients.create(System.getProperty("mongodb.uri"))) {
+            MongoDatabase sampleTrainingDB = mongoClient.getDatabase("sample_training");
+            MongoCollection<Document> gradesCollection = sampleTrainingDB.getCollection("grades");
+
+            // delete one document
+            Bson filter = eq("student_id", 10000);
+            DeleteResult result = gradesCollection.deleteOne(filter);
+            System.out.println(result);
+
+            // findOneAndDelete operation
+            filter = eq("student_id", 10002);
+            Document doc = gradesCollection.findOneAndDelete(filter);
+            System.out.println(doc.toJson(JsonWriterSettings.builder().indent(true).build()));
+
+            // delete many documents
+            filter = gte("student_id", 10000);
+            result = gradesCollection.deleteMany(filter);
+            System.out.println(result);
+
+            // delete the entire collection and its metadata (indexes, chunk metadata, etc).
+            gradesCollection.drop();
+        }
+    }
+}
diff --git a/src/main/java/com/mongodb/quickstart/MappingPOJO.java b/src/main/java/com/mongodb/quickstart/MappingPOJO.java
new file mode 100644
index 0000000000000000000000000000000000000000..37b8773d9b2a6cbf4646018f88dbd69be03b3b91
--- /dev/null
+++ b/src/main/java/com/mongodb/quickstart/MappingPOJO.java
@@ -0,0 +1,62 @@
+package com.mongodb.quickstart;
+
+import com.mongodb.ConnectionString;
+import com.mongodb.MongoClientSettings;
+import com.mongodb.client.MongoClient;
+import com.mongodb.client.MongoClients;
+import com.mongodb.client.MongoCollection;
+import com.mongodb.client.MongoDatabase;
+import com.mongodb.client.model.FindOneAndReplaceOptions;
+import com.mongodb.client.model.ReturnDocument;
+import com.mongodb.quickstart.models.Grade;
+import com.mongodb.quickstart.models.Score;
+import org.bson.codecs.configuration.CodecRegistry;
+import org.bson.codecs.pojo.PojoCodecProvider;
+import org.bson.conversions.Bson;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import static com.mongodb.client.model.Filters.eq;
+import static org.bson.codecs.configuration.CodecRegistries.fromProviders;
+import static org.bson.codecs.configuration.CodecRegistries.fromRegistries;
+
+public class MappingPOJO {
+
+    public static void main(String[] args) {
+        ConnectionString connectionString = new ConnectionString(System.getProperty("mongodb.uri"));
+        CodecRegistry pojoCodecRegistry = fromProviders(PojoCodecProvider.builder().automatic(true).build());
+        CodecRegistry codecRegistry = fromRegistries(MongoClientSettings.getDefaultCodecRegistry(), pojoCodecRegistry);
+        MongoClientSettings clientSettings = MongoClientSettings.builder()
+                                                                .applyConnectionString(connectionString)
+                                                                .codecRegistry(codecRegistry)
+                                                                .build();
+        try (MongoClient mongoClient = MongoClients.create(clientSettings)) {
+            MongoDatabase db = mongoClient.getDatabase("sample_training");
+            MongoCollection<Grade> grades = db.getCollection("grades", Grade.class);
+
+            // create a new grade.
+            Grade newGrade = new Grade().setStudentId(10003d)
+                                        .setClassId(10d)
+                                        .setScores(List.of(new Score().setType("homework").setScore(50d)));
+            grades.insertOne(newGrade);
+            System.out.println("Grade inserted.");
+
+            // find this grade.
+            Grade grade = grades.find(eq("student_id", 10003d)).first();
+            System.out.println("Grade found:\t" + grade);
+
+            // update this grade: adding an exam grade
+            List<Score> newScores = new ArrayList<>(grade.getScores());
+            newScores.add(new Score().setType("exam").setScore(42d));
+            grade.setScores(newScores);
+            Bson filterByGradeId = eq("_id", grade.getId());
+            FindOneAndReplaceOptions returnDocAfterReplace = new FindOneAndReplaceOptions().returnDocument(ReturnDocument.AFTER);
+            Grade updatedGrade = grades.findOneAndReplace(filterByGradeId, grade, returnDocAfterReplace);
+            System.out.println("Grade replaced:\t" + updatedGrade);
+
+            // delete this grade
+            System.out.println("Grade deleted:\t" + grades.deleteOne(filterByGradeId));
+        }
+    }
+}
diff --git a/src/main/java/com/mongodb/quickstart/Read.java b/src/main/java/com/mongodb/quickstart/Read.java
new file mode 100644
index 0000000000000000000000000000000000000000..6a1200b958aedd341c479b7a43536772df05429e
--- /dev/null
+++ b/src/main/java/com/mongodb/quickstart/Read.java
@@ -0,0 +1,63 @@
+package com.mongodb.quickstart;
+
+import com.mongodb.client.*;
+import org.bson.Document;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Consumer;
+
+import static com.mongodb.client.model.Filters.*;
+import static com.mongodb.client.model.Projections.*;
+import static com.mongodb.client.model.Sorts.descending;
+
+public class Read {
+
+    public static void main(String[] args) {
+        try (MongoClient mongoClient = MongoClients.create(System.getProperty("mongodb.uri"))) {
+            MongoDatabase sampleTrainingDB = mongoClient.getDatabase("sample_training");
+            MongoCollection<Document> gradesCollection = sampleTrainingDB.getCollection("grades");
+
+            // find one document with new Document
+            Document student1 = gradesCollection.find(new Document("student_id", 10000)).first();
+            System.out.println("Student 1: " + student1.toJson());
+
+            // find one document with Filters.eq()
+            Document student2 = gradesCollection.find(eq("student_id", 10000)).first();
+            System.out.println("Student 2: " + student2.toJson());
+
+            // find a list of documents and iterate throw it using an iterator.
+            FindIterable<Document> iterable = gradesCollection.find(gte("student_id", 10000));
+            MongoCursor<Document> cursor = iterable.iterator();
+            System.out.println("Student list with a cursor: ");
+            while (cursor.hasNext()) {
+                System.out.println(cursor.next().toJson());
+            }
+
+            // find a list of documents and use a List object instead of an iterator
+            List<Document> studentList = gradesCollection.find(gte("student_id", 10000)).into(new ArrayList<>());
+            System.out.println("Student list with an ArrayList:");
+            for (Document student : studentList) {
+                System.out.println(student.toJson());
+            }
+
+            // find a list of documents and print using a consumer
+            System.out.println("Student list using a Consumer:");
+            Consumer<Document> printConsumer = document -> System.out.println(document.toJson());
+            gradesCollection.find(gte("student_id", 10000)).forEach(printConsumer);
+
+            // find a list of documents with sort, skip, limit and projection
+            List<Document> docs = gradesCollection.find(and(eq("student_id", 10001), lte("class_id", 5)))
+                                                  .projection(fields(excludeId(), include("class_id", "student_id")))
+                                                  .sort(descending("class_id"))
+                                                  .skip(2)
+                                                  .limit(2)
+                                                  .into(new ArrayList<>());
+
+            System.out.println("Student sorted, skipped, limited and projected:");
+            for (Document student : docs) {
+                System.out.println(student.toJson());
+            }
+        }
+    }
+}
diff --git a/src/main/java/com/mongodb/quickstart/Update.java b/src/main/java/com/mongodb/quickstart/Update.java
new file mode 100644
index 0000000000000000000000000000000000000000..0aa4963c1c5881ac5c210c2f2a98ab1c2f3f818d
--- /dev/null
+++ b/src/main/java/com/mongodb/quickstart/Update.java
@@ -0,0 +1,72 @@
+package com.mongodb.quickstart;
+
+import com.mongodb.client.MongoClient;
+import com.mongodb.client.MongoClients;
+import com.mongodb.client.MongoCollection;
+import com.mongodb.client.MongoDatabase;
+import com.mongodb.client.model.FindOneAndUpdateOptions;
+import com.mongodb.client.model.ReturnDocument;
+import com.mongodb.client.model.UpdateOptions;
+import com.mongodb.client.result.UpdateResult;
+import org.bson.Document;
+import org.bson.conversions.Bson;
+import org.bson.json.JsonWriterSettings;
+
+import static com.mongodb.client.model.Filters.and;
+import static com.mongodb.client.model.Filters.eq;
+import static com.mongodb.client.model.Updates.*;
+
+public class Update {
+
+    public static void main(String[] args) {
+        JsonWriterSettings prettyPrint = JsonWriterSettings.builder().indent(true).build();
+
+        try (MongoClient mongoClient = MongoClients.create(System.getProperty("mongodb.uri"))) {
+            MongoDatabase sampleTrainingDB = mongoClient.getDatabase("sample_training");
+            MongoCollection<Document> gradesCollection = sampleTrainingDB.getCollection("grades");
+
+            // update one document
+            Bson filter = eq("student_id", 10000);
+            Bson updateOperation = set("comment", "You should learn MongoDB!");
+            UpdateResult updateResult = gradesCollection.updateOne(filter, updateOperation);
+            System.out.println("=> Updating the doc with {\"student_id\":10000}. Adding comment.");
+            System.out.println(gradesCollection.find(filter).first().toJson(prettyPrint));
+            System.out.println(updateResult);
+
+            // upsert
+            filter = and(eq("student_id", 10002d), eq("class_id", 10d));
+            updateOperation = push("comments", "You will learn a lot if you read the MongoDB blog!");
+            UpdateOptions options = new UpdateOptions().upsert(true);
+            updateResult = gradesCollection.updateOne(filter, updateOperation, options);
+            System.out.println("\n=> Upsert document with {\"student_id\":10002.0, \"class_id\": 10.0} because it doesn't exist yet.");
+            System.out.println(updateResult);
+            System.out.println(gradesCollection.find(filter).first().toJson(prettyPrint));
+
+            // update many documents
+            filter = eq("student_id", 10001);
+            updateResult = gradesCollection.updateMany(filter, updateOperation);
+            System.out.println("\n=> Updating all the documents with {\"student_id\":10001}.");
+            System.out.println(updateResult);
+
+            // findOneAndUpdate
+            filter = eq("student_id", 10000);
+            Bson update1 = inc("x", 10); // increment x by 10. As x doesn't exist yet, x=10.
+            Bson update2 = rename("class_id", "new_class_id"); // rename variable "class_id" in "new_class_id".
+            Bson update3 = mul("scores.0.score", 2); // multiply the first score in the array by 2.
+            Bson update4 = addToSet("comments", "This comment is uniq"); // creating an array with a comment.
+            Bson update5 = addToSet("comments", "This comment is uniq"); // using addToSet so no effect.
+            Bson updates = combine(update1, update2, update3, update4, update5);
+            // returns the old version of the document before the update.
+            Document oldVersion = gradesCollection.findOneAndUpdate(filter, updates);
+            System.out.println("\n=> FindOneAndUpdate operation. Printing the old version by default:");
+            System.out.println(oldVersion.toJson(prettyPrint));
+
+            // but I can also request the new version
+            filter = eq("student_id", 10001);
+            FindOneAndUpdateOptions optionAfter = new FindOneAndUpdateOptions().returnDocument(ReturnDocument.AFTER);
+            Document newVersion = gradesCollection.findOneAndUpdate(filter, updates, optionAfter);
+            System.out.println("\n=> FindOneAndUpdate operation. But we can also ask for the new version of the doc:");
+            System.out.println(newVersion.toJson(prettyPrint));
+        }
+    }
+}
diff --git a/src/main/java/com/mongodb/quickstart/models/Grade.java b/src/main/java/com/mongodb/quickstart/models/Grade.java
new file mode 100644
index 0000000000000000000000000000000000000000..2a2a9945a1c18125238d59aba7e344b201383614
--- /dev/null
+++ b/src/main/java/com/mongodb/quickstart/models/Grade.java
@@ -0,0 +1,81 @@
+package com.mongodb.quickstart.models;
+
+import org.bson.codecs.pojo.annotations.BsonProperty;
+import org.bson.types.ObjectId;
+
+import java.util.List;
+import java.util.Objects;
+
+public class Grade {
+
+    private ObjectId id;
+    @BsonProperty(value = "student_id")
+    private Double studentId;
+    @BsonProperty(value = "class_id")
+    private Double classId;
+    private List<Score> scores;
+
+    public ObjectId getId() {
+        return id;
+    }
+
+    public Grade setId(ObjectId id) {
+        this.id = id;
+        return this;
+    }
+
+    public Double getStudentId() {
+        return studentId;
+    }
+
+    public Grade setStudentId(Double studentId) {
+        this.studentId = studentId;
+        return this;
+    }
+
+    public Double getClassId() {
+        return classId;
+    }
+
+    public Grade setClassId(Double classId) {
+        this.classId = classId;
+        return this;
+    }
+
+    public List<Score> getScores() {
+        return scores;
+    }
+
+    public Grade setScores(List<Score> scores) {
+        this.scores = scores;
+        return this;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuffer sb = new StringBuffer("Grade{");
+        sb.append("id=").append(id);
+        sb.append(", student_id=").append(studentId);
+        sb.append(", class_id=").append(classId);
+        sb.append(", scores=").append(scores);
+        sb.append('}');
+        return sb.toString();
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o)
+            return true;
+        if (o == null || getClass() != o.getClass())
+            return false;
+        Grade grade = (Grade) o;
+        return Objects.equals(id, grade.id) && Objects.equals(studentId, grade.studentId) && Objects.equals(classId,
+                                                                                                            grade.classId) && Objects
+                .equals(scores, grade.scores);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(id, studentId, classId, scores);
+    }
+}
diff --git a/src/main/java/com/mongodb/quickstart/models/Score.java b/src/main/java/com/mongodb/quickstart/models/Score.java
new file mode 100644
index 0000000000000000000000000000000000000000..d1ef735fd8f949c505a933fcef49e8afc7346b0a
--- /dev/null
+++ b/src/main/java/com/mongodb/quickstart/models/Score.java
@@ -0,0 +1,51 @@
+package com.mongodb.quickstart.models;
+
+import java.util.Objects;
+
+public class Score {
+
+    private String type;
+    private Double score;
+
+    public String getType() {
+        return type;
+    }
+
+    public Score setType(String type) {
+        this.type = type;
+        return this;
+    }
+
+    public Double getScore() {
+        return score;
+    }
+
+    public Score setScore(Double score) {
+        this.score = score;
+        return this;
+    }
+
+    @Override
+    public String toString() {
+        final StringBuffer sb = new StringBuffer("Score{");
+        sb.append("type='").append(type).append('\'');
+        sb.append(", score=").append(score);
+        sb.append('}');
+        return sb.toString();
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o)
+            return true;
+        if (o == null || getClass() != o.getClass())
+            return false;
+        Score score1 = (Score) o;
+        return Objects.equals(type, score1.type) && Objects.equals(score, score1.score);
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(type, score);
+    }
+}
diff --git a/src/main/resources/logback.xml b/src/main/resources/logback.xml
new file mode 100644
index 0000000000000000000000000000000000000000..0aea751659497152176c6f8634035b4d653818b2
--- /dev/null
+++ b/src/main/resources/logback.xml
@@ -0,0 +1,10 @@
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
+        </encoder>
+    </appender>
+    <root level="warn">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>