com.hp.hpl.jena.sparql.engine.main
Class StageBuilder

java.lang.Object
  extended by com.hp.hpl.jena.sparql.engine.main.StageBuilder

public class StageBuilder
extends Object

The stage builder (there is only one) is a library that encapsulates evaluation of a basic graph pattern (BGP). Matching BGPs is an extension point of SPARQL; different entailment regimes plug in at this point. They are also an extension point in ARQ to connect to any datasource, the most common case being connectinbg to a Jena graph. The StageBuilder finds the registered StageGenerator, and calls it to evaluate a basic graph pattern that has any bound variables replaced by their value (in effect, an index join). Extension happens by registering a different StageGenerator in the context object for the execution. Setting the StageGenerator in the global context (ARQ) makes it available to all query execution created after the point of setting. Helper static methods for setting the stage generator are provided.


Constructor Summary
StageBuilder()
           
 
Method Summary
static QueryIterator execute(BasicPattern pattern, QueryIterator input, ExecutionContext execCxt)
           
static StageGenerator getGenerator()
           
static StageGenerator getGenerator(Context context)
           
static void init()
           
static void setGenerator(Context context, StageGenerator builder)
           
static StageGenerator standardGenerator()
           
 
Methods inherited from class java.lang.Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

StageBuilder

public StageBuilder()
Method Detail

execute

public static QueryIterator execute(BasicPattern pattern,
                                    QueryIterator input,
                                    ExecutionContext execCxt)

init

public static void init()

setGenerator

public static void setGenerator(Context context,
                                StageGenerator builder)

getGenerator

public static StageGenerator getGenerator(Context context)

getGenerator

public static StageGenerator getGenerator()

standardGenerator

public static StageGenerator standardGenerator()


Licenced under the Apache License, Version 2.0