This example shows how to perform some basic CRUD functions with MongoDB and the Java Driver

SimpleCRUDWithMonogDB

package mongoCrud;

import static com.mongodb.client.model.Filters.eq;

import org.bson.Document;

import com.mongodb.MongoClient;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;

public class MongoCrud {
	static MongoCollection<Document> collection;
	public static void main(String[] args) {

		MongoClient mongoClient = new MongoClient( "localhost" , 27017 );
		MongoDatabase database = mongoClient.getDatabase("mydb");
		collection = database.getCollection("people");
		collection.drop();

		//Insert three famous person documents
		//Top 3 from http://www.biographyonline.net/people/famous-100.html
		Document person1 = new Document("First Name", "Marilyn")
		.append("Last Name", "Monroe");

		Document person2 = new Document("First Name", "Abraham")
		.append("Last Name", "Lincoln");

		Document person3 = new Document("First Name", "Mother")
		.append("Last Name", "Teresa");

		collection.insertOne(person1);
		collection.insertOne(person2);
		collection.insertOne(person3);
		System.out.println("Result After Insert\n");
		printAllPeople();


		//Update a person document by Id
		Document updatedPerson = new Document("First Name", "Marilyn")
		.append("Last Name", "Monroe")
		.append("Description", "Actor");

		collection.findOneAndReplace(eq("First Name", "Marilyn"), updatedPerson);
		System.out.println("Result After Update\n");
		printAllPeople();	

		//Remove document from collection
		collection.deleteOne(eq("First Name", "Marilyn"));
		System.out.println("Result After Delete\n");
		printAllPeople();

		mongoClient.close();

	}

	private static void printAllPeople(){
		MongoCursor<Document> people = collection.find().iterator();
		while(people.hasNext())
			System.out.println(people.next());	
		System.out.println("\n");
		people.close();
	}

}