Module org.apache.jena.arq

Package org.apache.jena.sparql.expr.aggregate

Class AggregateRegistry

java.lang.Object

org.apache.jena.sparql.expr.aggregate.AggregateRegistry

public class AggregateRegistry
extends Object

Registry of custom aggregates There is only a single global registry of aggregates - it affects parsing and parsing happens before Context or Execution makes sense.

Constructor Summary

Constructors

Constructor	Description
AggregateRegistry()

Method Summary

Modifier and Type	Method	Description
static AccumulatorFactory	getAccumulatorFactory(String uri)	Return the AccumulatorFactory for a registered custom aggregate.
static org.apache.jena.graph.Node	getNoGroupValue(String uri)	Return the registered "no groups" value
static void	init()
static boolean	isRegistered(String uri)	Is the URI registered as an aggregate function?
static void	register(String uri, AccumulatorFactory accFactory)	Register a custom aggregate, with its associated factory for accumulators.
static void	register(String uri, AccumulatorFactory accFactory, org.apache.jena.graph.Node noGroupValue)
static void	unregister(String uri)	Remove a registration.

Methods inherited from class java.lang.Object

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

Constructor Details

AggregateRegistry

public AggregateRegistry()

Method Details

init

public static void init()

register

public static void register(String uri,
 AccumulatorFactory accFactory)

Register a custom aggregate, with its associated factory for accumulators.

register

public static void register(String uri,
 AccumulatorFactory accFactory,
 org.apache.jena.graph.Node noGroupValue)

unregister

public static void unregister(String uri)

Remove a registration.

getAccumulatorFactory

public static AccumulatorFactory getAccumulatorFactory(String uri)

Return the AccumulatorFactory for a registered custom aggregate.

getNoGroupValue

public static org.apache.jena.graph.Node getNoGroupValue(String uri)

Return the registered "no groups" value

isRegistered

public static boolean isRegistered(String uri)

Is the URI registered as an aggregate function?