search on specific field in mongodb/Mongodb-java

mongoDB : Java : Find documents where field is equal to value

Below snippet gets all documents where “firstName” is “Gopi”.

BasicDBObject query = new BasicDBObject();
query.put("firstName", "Gopi");
             
DBCursor cursor = collection.find(query);

import java.net.UnknownHostException;

import com.mongodb.BasicDBObject;
import com.mongodb.DBCursor;
import com.mongodb.MongoClient;
import com.mongodb.DB;
import com.mongodb.DBCollection;

public class FindDocument {

/* Step 1 : get mongoClient */
public static MongoClient getMongoClient(){
MongoClient mongoClient = null;
try {
mongoClient = new MongoClient( "localhost" , 27017 );
} catch (UnknownHostException e) {
e.printStackTrace();
}
return mongoClient;
}

public static void main(String args[]){
MongoClient mongoClient = getMongoClient();

/* Step 2: Connect to DB */
DB db = mongoClient.getDB("sample");

/*Step 3 : Get collection */
DBCollection collection = db.getCollection("employee");

/* Step 4 : Create Query object */
BasicDBObject query = new BasicDBObject();
query.put("firstName", "Gopi");

/* Step 5 : Get all documents */
DBCursor cursor = collection.find(query);

/* Step 6 : Print all documents */
while(cursor.hasNext()){
System.out.println(cursor.next());
}
}

}


Output

{ "_id" : 3.0 , "firstName" : "Gopi" , "lastName" : "Battu"}