Confusion about mongodb java driver [duplicate]

Question

I am a beginner to MongoDB and I'm playing around with it using the JAVA driver.

I have the following code

MongoClient client = new MongoClient();
DB d = client.getDB("world");
DBCollection c = d.getCollection("zips");
DBCursor cursor = c.find();

Now my question is that I want to use a simple cursor to go through the documents. The getDB() method is deprecated but it works fine. In the documentation it's mentioned that getDB can be replaced with MongoClient.getDatabase(); but getDatabase() returns a MongoDatabase not a DB.

Can someone point out the correct way to make a DBCursor without using any deprecated method. Thanks.

PS: I know there are frameworks like morphia, jongo etc but please keep them out of this discussion. I want to currently resort only to the JAVA driver. EDIT: The difference is about getting a cursor in the JAVA driver not between DB and MongoClient

Answer 1

Yes. Thats true. you can replace getDB with getDatabase. this is how you can use it.

        /**** Get database ****/
        // if database doesn't exists, MongoDB will create it for you
        MongoDatabase mydatabase = mongoClient.getDatabase("mydatabase");

        /**** Get collection / table from 'testdb' ****/
        // if collection doesn't exists, MongoDB will create it for you

        FindIterable<Document> mydatabaserecords = mydatabase.getCollection("collectionName").find();
        MongoCursor<Document> iterator = mydatabaserecords.iterator();
        while (iterator.hasNext()) {
            Document doc = iterator.next();
            // do something with document
        }

Example:

So lets say that your document is something like below:

{
  "name": "Newton",
  "age": 25
}

Then fields can be fetched as below

while (iterator.hasNext()) {
    Document doc = iterator.next();
    String name = doc.getString("name");
    int age = doc.getInteger("age");
    System.out.println("Name: " + name);
    System.out.println("Age: " + age);
}

I hope this clears your doubt.