Package org.aksw.qa.commons.sparql

Class SPARQLPrefixResolver

java.lang.Object

org.aksw.qa.commons.sparql.SPARQLPrefixResolver

public class SPARQLPrefixResolver
extends Object

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static class	SPARQLPrefixResolver.TwoStagePrefixMapping	Consists of two, a local and a global request mapping.

Field Summary

Fields

Modifier and Type	Field	Description
private static Properties	globalPrefixes	Refers to resource "prefixes.properties".
private static org.apache.jena.shared.PrefixMapping	globalPrefixMapping	This mapping will be used to refer to, if the local mapping (e.g.PREFIX declarations in the query itself) cannot resolve a prefix.
private static org.slf4j.Logger	LOGGER

Constructor Summary

Constructors

Constructor	Description
SPARQLPrefixResolver()

Method Summary

Modifier and Type	Method	Description
static String	addMissingPrefixes(String sparqlQuery)	Adds the declaration of a prefix, if its used in the sparql query, but not declared.
static org.apache.jena.shared.PrefixMapping	getGlobalPrefixMapping()	If you want to add/remove a prefix, this is your best bet.

Methods inherited from class java.lang.Object

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

Field Details

LOGGER

private static org.slf4j.Logger LOGGER

globalPrefixes

private static Properties globalPrefixes

Refers to resource "prefixes.properties". Left had side is a prefix, right hand side is a corresponding URI.

Prefixes will be loaded during loading of enclosing class, via static constructor.

globalPrefixMapping

private static org.apache.jena.shared.PrefixMapping globalPrefixMapping

This mapping will be used to refer to, if the local mapping (e.g.PREFIX declarations in the query itself) cannot resolve a prefix. Will be initialized with all prefixes in globalPrefixes

Constructor Details

SPARQLPrefixResolver

public SPARQLPrefixResolver()

Method Details

getGlobalPrefixMapping

public static org.apache.jena.shared.PrefixMapping getGlobalPrefixMapping()

If you want to add/remove a prefix, this is your best bet.

Returns:

The global prefix mapping, possibly containing all from resource "prefixes.properties"

addMissingPrefixes

public static String addMissingPrefixes(String sparqlQuery)

Adds the declaration of a prefix, if its used in the sparql query, but not declared. As global prefix source globalPrefixMapping is used, which is initialized with data from resource "prefixes.properties"

In query defined prefixes override.

If uris are given in the query body which can be represented with a prefix, the uris are replaced with a prefix and a prefix declaration will be added. E.g. "http://www.w3.org/1999/02/22-rdf-syntax-ns#type" is present, it will be replaced with "rdf:type", and prefix declaration for "rdf" will be added.

This will not remove unused prefix declarations.

if you wonder why keyword "a" is replaced, this is correct behavior. This is, because mapping for rdf: is set in a PrefixMap(its default in global).

Parameters:

sparqlQuery - a sparql query

Returns:

the same sparql query, but with missing PREFIX declarations added.