Mongo Java Array

Question

Quick and hopefully easy question.

DBObject res = collection.findOne(new BasicDBObject("_id",id));
// some_array is just an array of strings
Arr = res.get("some_array");

What type does Arr need to be? String[]? ArrayList?

nach0 · Accepted Answer · 2016-01-11 21:05:10Z

1

res.get() returns an Object, so that you need to do an explicit casting (you need to know the type of some_array field.

i.e:

List<Integer> values = (List<Integer>)res.get("some_array");

This is one of the reasons because I'm not supporter of bringing Java & MongoDB together.

edited Jan 11, 2016 at 21:05

answered Jan 11, 2016 at 20:56

nach0

3891 gold badge4 silver badges17 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

shelman · Accepted Answer · 2012-10-03 17:08:13Z

0

The Java driver will return arrays within the document as a List - for your example, you would want Arr to be a List<String>.

answered Oct 3, 2012 at 17:08

shelman

2,66916 silver badges17 bronze badges

1 Comment

nach0 Over a year ago

No at all. The Java driver returns Objects, not Arrays/Lists. Furthermore, by casting some_array to List<String> could trigger a ClassCastException if types mismatch.

Collectives™ on Stack Overflow

Mongo Java Array

2 Answers 2

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related