Package uk.gov.gchq.gaffer.store.util

Class AggregatorUtil

java.lang.Object

uk.gov.gchq.gaffer.store.util.AggregatorUtil

public final class AggregatorUtil
extends Object

Utility methods to help with doing aggregation of elements. Aggregation differs depending on if it ingest or query time aggregation. Ingest aggregation uses the groupBy properties in a Schema, whereas query time aggregation first checks the View to see if the groupBy properties have been overridden.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	AggregatorUtil.IngestElementBinaryOperator
static class	AggregatorUtil.IngestPropertiesBinaryOperator
static class	AggregatorUtil.IsElementAggregated
static class	AggregatorUtil.QueryElementBinaryOperator
static class	AggregatorUtil.QueryPropertiesBinaryOperator
static class	AggregatorUtil.ToElementKey
static class	AggregatorUtil.ToIngestElementKey	A Function that takes and element as input and outputs an element key that consists of the Group-by values in the Schema, the Identifiers and the Group.
static class	AggregatorUtil.ToQueryElementKey	A Function that takes and element as input and outputs an element key that consists of the Group-by values in the View, the Identifiers and the Group.

Method Summary

Modifier and Type	Method	Description
static Set<String>	getIngestGroupBy(String group, Schema schema)
static Map<String,Set<String>>	getIngestGroupBys(Schema schema)
static Set<String>	getQueryGroupBy(String group, Schema schema, View view)
static Map<String,Set<String>>	getQueryGroupBys(Schema schema, View view)
static Iterable<Element>	ingestAggregate(Iterable<? extends Element> elements, Schema schema)	Applies ingest aggregation to the provided iterable of Elements.
static Iterable<Element>	queryAggregate(Iterable<? extends Element> elements, Schema schema, View view)	Applies query time aggregation to the provided iterable of Elements.
static Iterable<Element>	queryAggregate(Iterable<? extends Element> elements, Schema schema, View view, boolean includeMatchedVertex)	Applies query time aggregation to the provided iterable of Elements.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

ingestAggregate

public static Iterable<Element> ingestAggregate(Iterable<? extends Element> elements,
                                                Schema schema)

Applies ingest aggregation to the provided iterable of Elements. This uses the groupBy properties in the provided Schema to group the elements prior to aggregating them.

NOTE - this is done in memory so the size of the iterable should be limited.

Parameters:

elements - the elements to be aggregated

schema - the schema containing the aggregators and groupBy properties to use

Returns:

the aggregated elements.

queryAggregate

public static Iterable<Element> queryAggregate(Iterable<? extends Element> elements,
                                               Schema schema,
                                               View view)

Applies query time aggregation to the provided iterable of Elements. This uses the groupBy properties in the provided View or Schema to group the elements prior to aggregating them. The Matched Vertex field is ignored during aggregation.

NOTE - this is done in memory so the size of the iterable should be limited.

Parameters:

elements - the elements to be aggregated

schema - the schema containing the aggregators and groupBy properties to use

view - the view containing the aggregators and groupBy properties to use

Returns:

the aggregated elements.

queryAggregate

public static Iterable<Element> queryAggregate(Iterable<? extends Element> elements,
                                               Schema schema,
                                               View view,
                                               boolean includeMatchedVertex)

Applies query time aggregation to the provided iterable of Elements. This uses the groupBy properties in the provided View or Schema to group the elements prior to aggregating them. Aggregation of Edges can optionally be configured to include the Matched Vertex field.

NOTE - this is done in memory so the size of the iterable should be limited.

Parameters:

elements - the elements to be aggregated

schema - the schema containing the aggregators and groupBy properties to use

view - the view containing the aggregators and groupBy properties to use

includeMatchedVertex - whether aggregation groups should include the Edge Matched Vertex

Returns:

the aggregated elements.

getIngestGroupBys

public static Map<String,Set<String>> getIngestGroupBys(Schema schema)

getQueryGroupBys

public static Map<String,Set<String>> getQueryGroupBys(Schema schema,
                                                             View view)

getIngestGroupBy

public static Set<String> getIngestGroupBy(String group,
                                           Schema schema)

getQueryGroupBy

public static Set<String> getQueryGroupBy(String group,
                                          Schema schema,
                                          View view)