org.openrdf.sesame.sail.query
Interface Query

All Known Implementing Classes:

GraphPatternQuery, SetOperator

public interface Query

The interface for queries.

Author:

Arjan Kleine, Jeen Broekstra, Arjohn Kampman

Method Summary

void	evaluate(RdfSource rdfSource, QueryAnswerListener listener) Evaluates the query on the data contained in the supplied RdfSource and reports the results to the supplied QueryAnswerListener.
String[]	getColumnHeaders() Gets the headers for the results table that is produced by this query.
void	getVariables(Collection variables) Gets all variables that are used in this query.

Method Detail

getColumnHeaders

public String[] getColumnHeaders()

Gets the headers for the results table that is produced by this query.

Returns:

An array containing as much strings as there are values in each query result.

getVariables

public void getVariables(Collection variables)

Gets all variables that are used in this query.

Parameters:

variables - A Collection to add the Var objects to.

evaluate

public void evaluate(RdfSource rdfSource,
                     QueryAnswerListener listener)
              throws SailQueryException

Evaluates the query on the data contained in the supplied RdfSource and reports the results to the supplied QueryAnswerListener.

Parameters:

rdfSource - An RdfSource containing the data to evaluate the query on.

listener - A QueryAnswerListener that will receive any query results.

Throws:

SailQueryException - An exception indicating that the query evaluation was stopped abnormally.