public static Bson geo2dsphere(final List<String> fieldNames) {
        notNull("fieldNames", fieldNames);
        return compoundIndex(fieldNames, new BsonString("2dsphere"));
    }
public static Bson geo2dsphere(final List<String> fieldNames) {
        notNull("fieldNames", fieldNames);
        return compoundIndex(fieldNames, new BsonString("2dsphere"));
    }
public static Bson geo2dsphere ( final List < String > fieldNames ) { notNull ( "fieldNames" , fieldNames ) ; return compoundIndex ( fieldNames , new BsonString ( "2dsphere" ) ) ; }
Create an index key for an ascending index on the given fields.

@param fieldNames the field names, which must contain at least one
@return the index specification
@mongodb.driver.manual core/indexes indexes
Create an index key for an ascending index on the given fields .