/**
* Convenience method that checks if the value that is used to sort
* data of this type is numeric. This only works if the value is set.
*
* @return boolean
*/
public function isNumeric() {
if ( isset( $this->m_dataitem ) ) {
return is_numeric( $this->m_dataitem->getSortKey() );
} else {
return false;
}
}
/**
* Create an SWMExpElement that encodes auxiliary data for representing
* values of the specified dataitem object in a simplified fashion.
* This is done for types of dataitems that are not supported very well
* in current systems, or that do not match a standard datatype in RDF.
* For example, time points (DITime) are encoded as numbers. The number
* can replace the actual time for all query and ordering purposes (the
* order in either case is linear and maps to the real number line).
* Only data retrieval should better use the real values to avoid that
* rounding errors lead to unfaithful recovery of data. Note that the
* helper values do not maintain any association with their original
* values -- they are a fully redundant alternative representation, not
* an additional piece of information for the main values. Even if
* decoding is difficult, they must be in one-to-one correspondence to
* the original value.
*
* For dataitems that do not have such a simplification, the method
* returns null.
*
* @note If a helper element is used, then it must be the same as
* getDataItemHelperExpElement( $dataItem->getSortKeyDataItem() ).
* Query conditions like ">" use sortkeys for values, and helper
* elements are always preferred in query answering.
*
* @param $dataItem SMWDataItem
* @return SMWExpElement or null
*/
public static function getDataItemHelperExpElement(SMWDataItem $dataItem)
{
if ($dataItem->getDIType() == SMWDataItem::TYPE_TIME) {
$lit = new SMWExpLiteral($dataItem->getSortKey(), 'http://www.w3.org/2001/XMLSchema#double', $dataItem);
return $lit;
} else {
return null;
}
}
/**
* Create an SWMExpElement that encodes auxiliary data for representing
* values of the specified dataitem object in a simplified fashion.
* This is done for types of dataitems that are not supported very well
* in current systems, or that do not match a standard datatype in RDF.
* For example, time points (DITime) are encoded as numbers. The number
* can replace the actual time for all query and ordering purposes (the
* order in either case is linear and maps to the real number line).
* Only data retrieval should better use the real values to avoid that
* rounding errors lead to unfaithful recovery of data. Note that the
* helper values do not maintain any association with their original
* values -- they are a fully redundant alternative representation, not
* an additional piece of information for the main values. Even if
* decoding is difficult, they must be in one-to-one correspondence to
* the original value.
*
* For dataitems that do not have such a simplification, the method
* returns null.
*
* @note If a helper element is used, then it must be the same as
* getDataItemHelperExpElement( $dataItem->getSortKeyDataItem() ).
* Query conditions like ">" use sortkeys for values, and helper
* elements are always preferred in query answering.
*
* @param $dataItem SMWDataItem
* @return SMWExpElement or null
*/
public static function getDataItemHelperExpElement(SMWDataItem $dataItem)
{
if ($dataItem->getDIType() == SMWDataItem::TYPE_TIME) {
return new SMWExpLiteral((string) $dataItem->getSortKey(), 'http://www.w3.org/2001/XMLSchema#double', '', $dataItem);
}
if ($dataItem->getDIType() == SMWDataItem::TYPE_GEO) {
return new SMWExpLiteral((string) $dataItem->getSortKey(), 'http://www.w3.org/2001/XMLSchema#string', '', $dataItem);
}
return null;
}
public function equals(SMWDataItem $di)
{
if ($di->getDIType() !== SMWDataItem::TYPE_TIME) {
return false;
}
return $di->getSortKey() === $this->getSortKey();
}
/**
* Method to return an array of fields=>values for a DataItem.
* This array is used to perform all insert operations into the DB.
* To optimize return minimum fields having indexes.
*
* @return array
*/
public function getInsertValues(SMWDataItem $dataItem)
{
return array('o_serialized' => $dataItem->getSerialization(), 'o_sortkey' => $dataItem->getSortKey());
}
private function getFirstLetterForCategory(DataItem $dataItem)
{
$sortKey = $dataItem->getSortKey();
if ($dataItem->getDIType() == DataItem::TYPE_WIKIPAGE) {
$sortKey = ApplicationFactory::getInstance()->getStore()->getWikiPageSortKey($dataItem);
}
return ByLanguageCollationMapper::getInstance()->findFirstLetterForCategory($sortKey);
}
/**
* Compatibility function for computing the old getDBkeys() array for
* the new SMW data items.
*
* @param $dataItem SMWDataItem
* @return array of mixed
*/
public static function getDBkeysFromDataItem(SMWDataItem $dataItem)
{
switch ($dataItem->getDIType()) {
case SMWDataItem::TYPE_STRING:
case SMWDataItem::TYPE_BLOB:
return array($dataItem->getString());
case SMWDataItem::TYPE_URI:
return array($dataItem->getSerialization());
case SMWDataItem::TYPE_WIKIPAGE:
return array($dataItem->getDBkey(), $dataItem->getNamespace(), $dataItem->getInterwiki(), $dataItem->getSortKey());
case SMWDataItem::TYPE_NUMBER:
return array($dataItem->getSerialization(), floatval($dataItem->getNumber()));
case SMWDataItem::TYPE_TIME:
$xsdvalue = $dataItem->getYear() . "/" . ($dataItem->getPrecision() >= SMWDITime::PREC_YM ? $dataItem->getMonth() : '') . "/" . ($dataItem->getPrecision() >= SMWDITime::PREC_YMD ? $dataItem->getDay() : '') . "T";
if ($dataItem->getPrecision() == SMWDITime::PREC_YMDT) {
$xsdvalue .= sprintf("%02d", $dataItem->getHour()) . ':' . sprintf("%02d", $dataItem->getMinute()) . ':' . sprintf("%02d", $dataItem->getSecond());
}
return array($xsdvalue, $dataItem->getSortKey());
case SMWDataItem::TYPE_BOOLEAN:
return $dataItem->getBoolean() ? array('1', 1) : array('0', 0);
case SMWDataItem::TYPE_CONTAINER:
return array(false);
case SMWDataItem::TYPE_CONCEPT:
return array($dataItem->getConceptQuery(), $dataItem->getDocumentation(), $dataItem->getQueryFeatures(), $dataItem->getSize(), $dataItem->getDepth());
case SMWDataItem::TYPE_PROPERTY:
return array($dataItem->getKey());
case SMWDataItem::TYPE_GEO:
$coordinateSet = $dataItem->getCoordinateSet();
return array($coordinateSet['lat'], $coordinateSet['lon']);
default:
return array(false);
}
}
