File Source for DatasetMem.php

<?php
require_once RDFAPI_INCLUDE_DIR . 'dataset/Dataset.php';
require_once RDFAPI_INCLUDE_DIR . 'dataset/NamedGraphMem.php';
require_once RDFAPI_INCLUDE_DIR . 'model/MemModel.php';
// ----------------------------------------------------------------------------------
// Class: DatasetMem
// ----------------------------------------------------------------------------------
/**
* In-memory implementation of a RDF dataset.
* A RDF dataset set is a collection of named RDF graphs.
*
* @version $Id: fsource_dataset__datasetDatasetMem.php.html 442 2007-06-01 16:19:26Z cax $
* @author Daniel Westphal (http://www.d-westphal.de)
* @author Chris Bizer <chris@bizer.de>
*
* @package dataset
* @access public
***/
class DatasetMem extends Dataset
{
/**
* Reference to a Memmodel that holds the default graph.
*
* @var resource Memmodel
* @access private
*/
var $defaultGraph;
/**
* Name of the DatasetMem.
*
* @var string
* @access private
*/
var $setName;
/**
* List of all NamedGraphs.
*
* @var array
* @access private
*/
var $graphs=array();
/**
* Constructor.
* You can supply a Dataset name.
*
* @param string
* @access public
*/
function DatasetMem($datasetName = null)
{
$this->setDatasetName($datasetName);
$this->defaultGraph=new MemModel();
}
// === Graph level methods ========================
/**
* Sets the Datasets name.
*
* @param string
* @access public
*/
function setDatasetName($datasetName)
{
$this->setName=$datasetName;
}
/**
* Returns the Datasets name.
*
* @return string
* @access public
*/
function getDatasetName()
{
return $this->setName;
}
/**
* Adds a NamedGraph to the set. Will replace a NamedGraph with the same name that is already in the set.
*
* @param NamedGraphMem
*/
function addNamedGraph(&$graph)
{
$graphNameURI=$graph->getGraphName();
$this->graphs[$graphNameURI]=&$graph;
}
/**
* Overwrites the existting default graph.
*
* @param MemModel
*/
function setDefaultGraph(&$graph)
{
$this->defaultGraph=&$graph;
}
/**
* Returns a reference to the defaultGraph
* @return Model
*/
function &getDefaultGraph()
{
return $this->defaultGraph;
}
/**
* Returns true, if an defaultGraph exists. False otherwise .
*
* @return boolean
*/
function hasDefaultGraph()
{
return $this->defaultGraph != null;
}
/**
* Removes a NamedGraph from the set. Nothing happens
* if no graph with that name is contained in the set.
*
* @param string
*/
function removeNamedGraph($graphName)
{
unset($this->graphs[$graphName]);
}
/**
* Tells wether the Dataset contains a NamedGraph.
*
* @param string
* @return boolean
*/
function containsNamedGraph($graphName)
{
return isset($this->graphs[$graphName]) === true;
}
/**
* Returns the NamedGraph with a specific name from the Dataset.
* Changes to the graph will be reflected in the set.
*
* @param string
* @return NamedGraphMem or NULL
*/
function &getNamedGraph($graphName)
{
if (!isset($this->graphs[$graphName])) return NULL;
return $this->graphs[$graphName];
}
/**
* Returns the names of the namedGraphs in this set as strings in an array.
*
* @return Array
*/
function listGraphNames()
{
return array_keys($this->graphs);
}
/**
* Creates a new NamedGraph and adds it to the set. An existing
* graph with the same name will be replaced.The name of the NamedGraph to be created ; must be an URI
*
* @param string
* @param string
* @return NamedGraphMem
*/
function &createGraph($graphName,$baseURI = null)
{
$this->graphs[$graphName]=new NamedGraphMem($graphName,$baseURI);
return $this->getNamedGraph($graphName);
}
/**
* Deletes all NamedGraphs from the set.
*/
function clear()
{
$this->graphs = array();
}
/**
* Returns the number of NamedGraphs in the set. Empty graphs
* are counted.
*
* @return int
*/
function countGraphs()
{
return count($this->graphs);
}
/**
* Returns the NamedGraph with a specific offset in the dataset.
* Changes to the graph will be reflected in the set.
*
* @param int
* @return NamedGraphMem or null
* @access private
*/
function &getGraphWithOffset($offset)
{
$i=0;
foreach ($this->graphs as $graph)
{
if (($i++)==$offset)
return $graph;
}
$n = null;
return $n;
}
/**
* Returns an iterator over all {@link NamedGraph}s in the set.
*
* @return IteratorAllGraphsMem
*/
function &listNamedGraphs()
{
require_once RDFAPI_INCLUDE_DIR . 'dataset/IteratorAllGraphsMem.php';
$m = new IteratorAllGraphsMem($this);
return $m;
}
/**
* Tells wether the set contains any NamedGraphs.
*
* @return boolean
*/
function isEmpty()
{
return $this->countGraphs() == 0;
}
/**
* Adds all named graphs of the other dataset to this dataset.
*
* @param Dataset
*/
function addAll($otherDataset)
{
for($iterator = $otherDataset->listNamedGraphs(); $iterator->valid(); $iterator->next())
{
$current=$iterator->current();
$this->graphs[$current->getGraphName()]=$current;
}
if ($otherDataset->hasDefaultGraph())
{
$this->defaultGraph = $this->defaultGraph->unite($otherDataset->getDefaultGraph());
}
}
// === Quad level methods ========================
/**
* Adds a quad to the Dataset. The argument must not contain any
* wildcards. If the quad is already present, nothing happens. A new
* named graph will automatically be created if necessary.
*
* @param Quad
*/
function addQuad(&$quad)
{
$graphName=$quad->getGraphName();
if ($this->containsNamedGraph($graphName->getLabel())===false)
$this->createGraph($graphName->getLabel());
$this->graphs[$graphName->getLabel()]->add($quad->getStatement());
}
/**
* Tells wether the Dataset contains a quad or
* quads matching a pattern.
*
* @param Resource $graphName
* @param Resource $subject
* @param Resource $predicate
* @param Resource $object
* @return boolean
*/
function containsQuad($graphName,$subject,$predicate,$object)
{
if($graphName!=null)
{
if ($this->containsNamedGraph($graphName->getLabel())!==true)
return false;
return ($this->graphs[$graphName->getLabel()]->findFirstMatchingStatement($subject,$predicate,$object)!=null);
}
foreach ($this->graphs as $graph)
{
if ($graph->findFirstMatchingStatement($subject,$predicate,$object)!=null)
return true;
};
return false;
}
/**
* Deletes a Quad from the RDF dataset.
*
* @param Quad
*/
function removeQuad($quad)
{
$graphName=$quad->getGraphName();
if($graphName!=null)
{
if ($this->containsNamedGraph($graphName->getLabel())!==true)
return;
return ($this->graphs[$graphName->getLabel()]->remove($quad->getStatement())!=null);
}
foreach ($this->graphs as $graph)
{
$graph->remove($quad->getStatement());
};
}
/**
* Counts the Quads in the RDF dataset. Identical Triples in
* different NamedGraphs are counted individually.
*
* @return int
*/
function countQuads()
{
$count=0;
foreach ($this->graphs as $graph)
{
$count+=$graph->size();
}
return $count;
}
/**
* Finds Statements that match a quad pattern. The argument may contain
* wildcards.
*
* @param Resource or Null
* @param Resourceor Null
* @param Resource or Null
* @param Resource or Null
* @return Iterator
*/
function &findInNamedGraphs($graph,$subject,$predicate,$object,$returnAsTriples = false)
{
if ($graph!=null)
{
$findGraph=&$this->getNamedGraph($graph->getLabel());
if($findGraph==null)
$findGraph=new MemModel();
return $findGraph->iterFind($subject,$predicate,$object);
}
require_once RDFAPI_INCLUDE_DIR . 'dataset/IteratorFindQuadsMem.php';
$m = new IteratorFindQuadsMem($subject,$predicate,$object,$this->listNamedGraphs(),$returnAsTriples);
return $m;
}
/**
* Finds Statements that match a pattern in the default Graph. The argument may contain
* wildcards.
*
* @param Resource or Null
* @param Resource or Null
* @param Resource or Null
* @return Iterator
*/
function &findInDefaultGraph($subject,$predicate,$object)
{
return $this->defaultGraph->iterFind($subject,$predicate,$object);
}
}
?>

Documentation generated on Fri, 1 Jun 2007 16:48:42 +0200 by phpDocumentor 1.3.2

Source for file DatasetMem.php