How to insert multiple documents at once in MongoDB through Java

DBCollection.insert accepts a parameter of type DBObject, List<DBObject> or an array of DBObjects for inserting multiple documents at once. You are passing in a string array.

You must manually populate documents(DBObjects), insert them to a List<DBObject> or an array of DBObjects and eventually insert them.

DBObject document1 = new BasicDBObject();document1.put("name", "Kiran");document1.put("age", 20);DBObject document2 = new BasicDBObject();document2.put("name", "John");List<DBObject> documents = new ArrayList<>();documents.add(document1);documents.add(document2);collection.insert(documents);

The above snippet is essentially the same as the command you would issue in the MongoDB shell:

db.people.insert( [ {name: "Kiran", age: 20}, {name: "John"} ]);

Before 3.0, you can use below code in Java

DB db = mongoClient.getDB("yourDB");            DBCollection coll = db.getCollection("yourCollection");            BulkWriteOperation builder = coll.initializeUnorderedBulkOperation();            for(DBObject doc :yourList)            {                builder.insert(doc);            }            BulkWriteResult result = builder.execute();            return result.isAcknowledged();

If you are using mongodb version 3.0 , you can use

MongoDatabase database = mongoClient.getDatabase("yourDB");            MongoCollection<Document> collection = database.getCollection("yourCollection");            collection.insertMany(yourDocumentList);

As of MongoDB 2.6 and 2.12 version of the driver you can also now do a bulk insert operation. In Java you could use the BulkWriteOperation. An example use of this could be:

DBCollection coll = db.getCollection("user");BulkWriteOperation bulk = coll.initializeUnorderedBulkOperation();bulk.find(new BasicDBObject("z", 1)).upsert().update(new BasicDBObject("$inc", new BasicDBObject("y", -1)));bulk.find(new BasicDBObject("z", 1)).upsert().update(new BasicDBObject("$inc", new BasicDBObject("y", -1)));bulk.execute();