Indexes

The Indexes class provides static factory methods for all the MongoDB Index key types.
Each method returns an instance of the Bson type, which can in turn be used with the createIndex methods.

For brevity, you may choose to import the methods of the Indexes class statically:

import com.mongodb.client.model.Indexes.*;

All the examples below assume this static import.

Ascending

To specify an ascending index key, use one of the ascending methods.

This example specifies an ascending index key for the quantity field:

ascending("quantity")

This example specifies a compound index key composed of the quantity field sorted in ascending order and the totalAmount field sorted in ascending order:

ascending("quantity", "totalAmount") 

Descending

To specify a descending index key, use one of the descending methods.

This example specifies a descending index key on the quantity field:

descending("quantity")

This example specifies a compound index key composed of the quantity field sorted in descending order and the totalAmount field sorted in descending order:

descending("quantity", "totalAmount") 

Compound indexes

To specify a compound index, use the compoundIndex method.

This example specifies a compound index key composed of the quantity field sorted in ascending order, followed by the totalAmount field sorted in ascending order, followed by the orderDate field sorted in descending order:

compoundIndex(ascending("quantity", "totalAmount"), descending("orderDate"))

Text Index

To specify a text index key, use the text method.

This example specifies a text index key for the description field:

text("description")

Hashed Index

To specify a hashed index key, use the hashed method.

This example specifies a hashed index key for the timestamp field:

hashed("timestamp")

Geospatial Indexes

There are also helpers for creating the index keys for the various geospatial indexes supported by mongodb.

2dsphere

To specify a 2dsphere index key, use one of the geo2dsphere methods.

This example specifies a 2dsphere index on the location field:

geo2dsphere("location")

2d

To specify a 2d index key, use the geo2d method.

important

A 2d index is for data stored as points on a two-dimensional plane and is intended for legacy coordinate pairs used in MongoDB 2.2 and earlier.

This example specifies a 2d index on the points field:

geo2d("points")

geoHaystack

To specify a geoHaystack index key, use the geoHaystack method.

important

For queries that use spherical geometry, a 2dsphere index is a better option than a haystack index. 2dsphere indexes allow field reordering; geoHaystack indexes require the first field to be the location field. Also, geoHaystack indexes are only usable via commands and so always return all results at once.

This example specifies a geoHaystack index on the position field and an ascending index on the type field:

geoHaystack("position", ascending("type"))