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Is it possible to convert a MongoDb query result into a stream and collect it?

For example, to get a list of _id values, something like this:

getMongoDatabaseInstance()
                .getCollection("some_collection_name")
                .find()
                .projection(new Document("_id", 1 ))
                .map(d -> d.getString("_id") )
                .collect(Collectors.toList());
This results in a compilation error:
The method collect(Collectors.toList()) is undefined for the type MongoIterable<String>
because a MongoIterable is not a stream and cannot be collected.
Of course, I could declare a cursor and iterate over the result set, but that requires adding declarations and loops etc. I need to collect small number of documents at many places in my program, and it would be much more clean and easy to convert them to a stream and collect.
Is that possible?
Try use StreamSupport#stream
By using this utility you can convert iterable interface to stream or parallel stream. 
StreamSupport.stream(getMongoDatabaseInstance()
             .getCollection("some_collection_name")
             .find()
             .projection(new Document("_id", 1 )).spliterator(),false)
             .map(d->d.getString("_id"))
             .collect(Collectors.toList());
                I would suggest splitting the spliterator as a local variable. Also, though this should work, the client library until some version for mongo didn't support the implementation.
– Naman
                May 17, 2020 at 11:50
        
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