org.openanzo.glitter.query
Class SerialQueryExecutor

java.lang.Object
  org.openanzo.glitter.query.SerialQueryExecutor

All Implemented Interfaces:

QueryExecutor

public class SerialQueryExecutor
extends java.lang.Object
implements QueryExecutor

The SerialQueryExecutor is the standard QueryExecutor. It uses the supplied execution plan to generate bindings serially; it repeatedly asks a solution generator to generate bindings for as large a part of the query as it can, and the executor composes these results into the final SolutionSet.

Author:

lee

Constructor Summary

SerialQueryExecutor()
Constructor.

Method Summary

boolean	composedSolutions() Clients of an executor need to know whether the executor had a handle in putting together results, to know if reordering might be necessary.
SolutionSet	executeQuery() Executes the query, returning a result set.
void	initialize(EngineConfig config, QueryController controller, SolutionGenerator sg, QueryExecutionPlan plan) Initialize the executor with information on the query.

Methods inherited from class java.lang.Object

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

Constructor Detail

SerialQueryExecutor

public SerialQueryExecutor()

Constructor.

Method Detail

initialize

public void initialize(EngineConfig config,
                       QueryController controller,
                       SolutionGenerator sg,
                       QueryExecutionPlan plan)

Description copied from interface: QueryExecutor

Initialize the executor with information on the query.

Specified by:

initialize in interface QueryExecutor

Parameters:

config - The engine configuration in effect.

controller - The query controller with information on the parsed and prepared query.

sg - The backend solution generator.

plan - The query execution plan.

executeQuery

public SolutionSet executeQuery()
                         throws GlitterException

Description copied from interface: QueryExecutor

Executes the query, returning a result set.

Specified by:

executeQuery in interface QueryExecutor

Returns:

A SolutionSet with the bindings from executing the query against an RDFDataset.

Throws:

GlitterException

composedSolutions

public boolean composedSolutions()

Description copied from interface: QueryExecutor

Clients of an executor need to know whether the executor had a handle in putting together results, to know if reordering might be necessary. Executors are considered trustworthy, while backends may not be.

Specified by:

composedSolutions in interface QueryExecutor

Returns:

true if results were composed from pieces provided by a backend; false if all results were generated by the backend.