I want to retrieve 200 000 data from db from mongodb using morphia.

Earlier I was using

query.asList()

which gave me out of memory exception I tried changing it to

query.batchSize(50).asList()

but with no luck.

I update my code to

Iterable<DataStreams> iterable= query.fetch();
            Iterator<DataStreams> iterator=iterable.iterator();
            while (iterator.hasNext()) {
               dataStreamsList.add(iterator.next());                
            }           
           System.out.println("iteration done");