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Java equivalent of scala query in mongodb

What is the equivalent cde in Java:

var result = collectionName.findOne()
println(result.get("name").toString)

To elaborate, This is my sample db:

{ "_id" : ObjectId("4ca039f7a5b75ab98a44b149"), "name" : "kaustubh", "country" : "india" }
{ "_id" : ObjectId("4ca03a85a12344a5e47bcc5c"), "name" : "rahul", "country" : "pakistan" }
{ "_id" : ObjectId("4ca03a9ea12344a5e47bcc5d"), "name" : "swapnil", "country" : "lank开发者_如何学JAVAa" }
{ "_id" : ObjectId("4ca03b19a12344a5e47bcc5e"), "name" : "sagar", "country" : "nepal" }

i am running the following query on it:

query.put("country", "india");
  DBCursor cursor = collection.find(query);
  while (cursor.hasNext()) {
    System.out.println(cursor.next());
}

that prints:

{ "_id" : { "$oid" : "4ca04b6b37a85ab92557218a"} , "name" : "kaustubh" , "country" : "india"}

as many times as the pair exists in the collection.

how do I formulate a query to get all the names, once and get the count for them.I read the docs, and didnt stumble upon any way to do it.


Try this

query.put("name", "kaustubh");
DBObject myDoc = collection.findOne(query);
System.out.println(myDoc);
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