org.locationtech.geowave.core.index

Interface CustomIndexStrategy<E,C extends Persistable>

Type Parameters:

E - The entry type (such as SimpleFeature, GridCoverage, or whatever type the adapter uses)

C - The custom constraints type, can be any arbitrary type, although should be persistable so that it can work outside of just client code (such as server-side filtering, map-reduce, or spark)

All Superinterfaces:

Persistable

All Known Implementing Classes:

CustomAttributeIndex, CustomIndex, CustomIndexExample.UUIDIndexStrategy, EnumIndexStrategy, TextIndexStrategy

public interface CustomIndexStrategy<E,C extends Persistable>
extends Persistable

This interface is the most straightforward mechanism to add custom indexing of any arbitrary logic to a GeoWave data store. This can simply be two functions that tell GeoWave how to index an entry on ingest and how to query the index based on a custom constraints type.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	CustomIndexStrategy.PersistableBiPredicate<E,C extends Persistable>

Method Summary

Modifier and Type	Method and Description
Class<C>	getConstraintsClass()
default CustomIndexStrategy.PersistableBiPredicate<E,C>	getFilter(C constraints) Optionally a custom index strategy can enable additional filtering beyond just the query ranges (termed "fine-grained" filtering in documentation).
InsertionIds	getInsertionIds(E entry) This is the function that is called on ingest to tell GeoWave how to index the entry within this custom index - the insertion IDs are a set of partition and sort keys, either of which could be empty or null as needed (with the understanding that each partition key represents a unique partition in the backend datastore)
QueryRanges	getQueryRanges(C constraints) This is the function that is called on query, when given a query with the constraints type.

Methods inherited from interface org.locationtech.geowave.core.index.persist.Persistable

fromBinary, toBinary

Method Detail

getInsertionIds

InsertionIds getInsertionIds(E entry)

This is the function that is called on ingest to tell GeoWave how to index the entry within this custom index - the insertion IDs are a set of partition and sort keys, either of which could be empty or null as needed (with the understanding that each partition key represents a unique partition in the backend datastore)

Parameters:

entry - the entry to be indexed on ingest

Returns:

the insertion IDs representing how to index the entry

getQueryRanges

QueryRanges getQueryRanges(C constraints)

This is the function that is called on query, when given a query with the constraints type. The constraints type can be any arbitrary type although should be persistable so that it can work outside of just client code (such as server-side filtering, map-reduce, or spark). The query ranges are a set of partition keys and ranges of sort keys that fully include all rows that may match the constraints.

Parameters:

constraints - the query constraints

Returns:

query ranges that represent valid partition and ranges of sort keys that fully include all rows that may match the constraints

getConstraintsClass

Class<C> getConstraintsClass()

getFilter

default CustomIndexStrategy.PersistableBiPredicate<E,C> getFilter(C constraints)

Optionally a custom index strategy can enable additional filtering beyond just the query ranges (termed "fine-grained" filtering in documentation). This requires reading rows from disk and evaluating a predicate so it is inherently slower than using query ranges but it is flexible enough to handle any additional evaluation criteria required.

Returns:

A predicate that should be used for "fine-grained" filter evaluation