How to insert multiple document into a MongoDB collection using Java?

You can insert multiple documents into an existing collection in MongoDB using the insertMany() method.
db.coll.insert(docArray)
Where,
db is the database.
db is the database.
coll is the collection (name) in which you want to insert the document
coll is the collection (name) in which you want to insert the document
docArray is the array of documents you want to insert.
docArray is the array of documents you want to insert.
> use myDatabase()
switched to db myDatabase()
> db.createCollection(sample)
{ "ok" : 1 }
> db.test.insert([{name:"Ram", age:26, city:"Mumbai"}, {name:"Roja", age:28,
city:"Hyderabad"}, {name:"Ramani", age:35, city:"Delhi"}])
BulkWriteResult({
   "writeErrors" : [ ],
   "writeConcernErrors" : [ ],
   "nInserted" : 3,
   "nUpserted" : 0,
   "nMatched" : 0,
   "nModified" : 0,
   "nRemoved" : 0,
   "upserted" : [ ]
})
In Java, you can create insert a document into a collection using the insertMany() method of the com.mongodb.client.MongoCollection interface. This method accepts a list (object) congaing the documents you want to insert as a parameter.
Therefore to create a collection in MongoDB using Java program −
Make sure you have installed MongoDB in your system
Make sure you have installed MongoDB in your system
Add the following dependency to its pom.xml file of your Java project.
Add the following dependency to its pom.xml file of your Java project.
<dependency>
   <groupId>org.mongodb</groupId>
   <artifactId>mongo-java-driver</artifactId>
   <version>3.12.2</version>
</dependency>
Create a MongoDB client by instantiating the MongoClient class.
Create a MongoDB client by instantiating the MongoClient class.
Connect to a database using the getDatabase() method.
Connect to a database using the getDatabase() method.
Prepare the documents to be inserted.
Prepare the documents to be inserted.
Get the object of the collection into which you want to insert the documents, using the getCollection() method.
Get the object of the collection into which you want to insert the documents, using the getCollection() method.
Create a List object adding all the created documents t it.
Create a List object adding all the created documents t it.
Invoke the insertMany() method by passing the list object as a parameter.
Invoke the insertMany() method by passing the list object as a parameter.
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import java.util.ArrayList;
import java.util.List;
import org.bson.Document;
import com.mongodb.MongoClient;
public class InsertingMultipleDocuments {
   public static void main( String args[] ) {
      //Creating a MongoDB client
      MongoClient mongo = new MongoClient( "localhost" , 27017 );
      //Connecting to the database
      MongoDatabase database = mongo.getDatabase("myDatabase");
      //Creating a collection object
      MongoCollection<Document> collection =
      database.getCollection("sampleCollection");
      Document document1 = new Document("name", "Ram").append("age", 26).append("city", "Hyderabad");
      Document document2 = new Document("name", "Robert").append("age", 27).append("city", "Vishakhapatnam");
      Document document3 = new Document("name", "Rhim").append("age", 30).append("city", "Delhi");
      //Inserting the created documents
      List<Document> list = new ArrayList<Document>();
      list.add(document1);
      list.add(document2);
      list.add(document3);
      collection.insertMany(list);
      System.out.println("Documents Inserted");
   }
}
Documents Inserted