/**
  * This method takes a json encoded rdf-model and a reference to aa (usually empty) MemModel, parses the json
  * string and adds the statements to the given MemModel.
  *
  * @param string $jsonString The string that contains the rdf model, encoded as a json-string.
  * @param MemModel $model A reference to the model, where to add the statements, usually an empty MemModel.
  */
 public function generateModelFromString($jsonString, $model)
 {
     $jsonModel = array();
     $jsonModel = json_decode($jsonString, true);
     // throws an excpetion if json model was corrupt
     if (!is_array($jsonModel)) {
         throw new Exception('error in json string');
     }
     foreach ($jsonModel as $subject => $remain) {
         foreach ($remain as $predicate => $object) {
             $s = strpos($subject, '_') === 0 ? new BlankNode(substr($subject, 2)) : new Resource($subject);
             $p = new Resource($predicate);
             foreach ($object as $obj) {
                 if ($obj['type'] === 'uri') {
                     $o = new Resource($obj['value']);
                 } else {
                     if ($obj['type'] === 'bnode') {
                         $o = new BlankNode(substr($obj['value'], 2));
                     } else {
                         $dtype = isset($obj['datatype']) ? $obj['datatype'] : '';
                         $lang = isset($obj['lang']) ? $obj['lang'] : '';
                         $oVal = $obj['value'];
                         $o = new Literal($oVal, $lang);
                         $o->setDatatype($dtype);
                     }
                 }
                 $model->add(new Statement($s, $p, $o));
             }
         }
     }
 }

 function _doFindFromFile($file, &$model)
 {
     $nullVarURIs = array('var:x', 'var:y', 'var:z');
     $mod = new MemModel();
     $mod->load($file);
     $return = new MemModel();
     foreach ($mod->triples as $statement) {
         if (in_array($statement->getLabelSubject(), $nullVarURIs)) {
             $findS = null;
         } else {
             $findS = $statement->getSubject();
         }
         if (in_array($statement->getLabelPredicate(), $nullVarURIs)) {
             $findP = null;
         } else {
             $findP = $statement->getPredicate();
         }
         if (in_array($statement->getLabelObject(), $nullVarURIs)) {
             $findO = null;
         } else {
             $findO = $statement->getObject();
         }
         $return->addModel($model->find($findS, $findP, $findO));
     }
     return $return;
 }

 function testSerialize()
 {
     $ser = new JsonSerializer();
     $jsonString = $ser->serialize($this->model);
     $memModel = new MemModel();
     $memModel->loadFromString($jsonString, 'json');
     $this->assertTrue($this->model->equals($memModel));
 }

 function _generateModel($num, $ind)
 {
     $model = new MemModel();
     $model->index($ind);
     for ($i = 0; $i < $num; $i++) {
         $subs[$i] = new Resource('http://www.example.org/sub' . $i % 3);
         $preds[$i] = new Resource('http://www.example.org/pred' . $i % 5);
         $objs[$i] = new Resource('http://www.example.org/obj' . $i % 9);
         $stat = new Statement($subs[$i], $preds[$i], $objs[$i]);
         $model->add($stat);
     }
     return $model;
 }

 function testGenerateModelFromString()
 {
     $parser = new JsonParser();
     $model = new MemModel('http://example.com/');
     try {
         $parser->generateModelFromString($this->modelString, $model);
     } catch (Exception $e) {
         $this->fail($e->getMessage());
     }
     #echo "<pre>";
     #print_r($model);
     global $short_datatype;
     $model2 = new MemModel('http://example.com/');
     // Ceate new statements and add them to the model
     $statement1 = new Statement(new Resource('http://example.org/about'), new Resource('http://purl.org/dc/elements/1.1/creator'), new Literal('Anna Wilder'));
     $statement2 = new Statement(new Resource('http://example.org/about'), new Resource("http://purl.org/dc/elements/1.1/title"), new Literal('Annas Homepage', 'en'));
     $statement3 = new Statement(new Resource('http://example.org/about'), new Resource('http://xmlns.com/foaf/0.1/maker'), new BlankNode('person'));
     $statement4 = new Statement(new BlankNode('person'), new Resource("http://xmlns.com/foaf/0.1/homepage"), new Resource('http://example.org/about'));
     $statement5 = new Statement(new Resource('http://example.org/about'), new Resource("http://purl.org/dc/elements/1.1/title2"), new Literal('Anns HP', 'en', $short_datatype['STRING']));
     $statement6 = new Statement(new Resource('http://example.org/about'), new Resource("http://purl.org/dc/elements/1.1/title2"), new Literal('Anns HP', 'en', $short_datatype['INTEGER']));
     $statement7 = new Statement(new BlankNode('person'), new Resource("http://example.com/testProp1"), new Literal("\"double quote\nnewline\ttab\rcarriage return\\reverse solidus"));
     $model2->add($statement1);
     $model2->add($statement2);
     $model2->add($statement3);
     $model2->add($statement4);
     $model2->add($statement5);
     $model2->add($statement7);
     $this->assertTrue($model->containsAll($model2));
     $model2->remove($statement5);
     $model2->add($statement6);
     $this->assertFalse($model->containsAll($model2));
     #echo "<pre>";
     #print_r($model2);
     #echo "</pre>";
 }

 function testRdfParser()
 {
     $_SESSION['test'] = 'Rdf- Parser Empty Resource test';
     $mod1 = new MemModel();
     $mod2 = new MemModel();
     $mod1->load('emptyResource.rdf');
     $mod2->load('emptyResource_serialized.rdf');
     if ($mod1->equals($mod2)) {
         $pass = true;
     } else {
         $pass = false;
     }
     $this->assertTrue($pass);
 }

 function testIsEquals()
 {
     foreach ($_SESSION['rdf_positive_tests'] as $key => $value) {
         $model1 = new MemModel();
         $model2 = new MemModel();
         $file = $value;
         $_SESSION['test'] =& $value;
         $_SESSION['key'] =& $key;
         $model1->load(TESTCASES_DIR . $file . ".rdf");
         $_SESSION['mod1'] = $model1;
         $model2->load(TESTCASES_DIR . $file . ".nt");
         $_SESSION['mod2'] = $model2;
         $this->assertTrue($model1->equals($model2));
     }
 }

 /**
  * loads namespaces from file or rewrites from configuration model
  */
 function loadNamespaces($url)
 {
     if ($url) {
         $nmsp_m = new MemModel();
         $nmsp_m->load($url);
         $this->ns = $nmsp_m->getParsedNamespaces();
         if (!$this->ns) {
             trigger_error("The file:" . $url . "does not contain any namespace declarations." . "The prefixes from the configuration model will be used instead");
         }
     } else {
         $nmsp = $this->m->getParsedNamespaces();
         if ($nmsp) {
             $this->ns = RAPpubbyURIrewriter::rewrNamespaces($nmsp);
         }
     }
 }

 /**
  * parser overwrites the prefixes defined in the default_prefixes array
  */
 function testOverwritingDefaultParser()
 {
     $_SESSION['test'] = 'Overwriting default parser test';
     $string = "<?xml version='1.0'?>\n \t\t\t\t<rdf:RDF xmlns:rdf='http://www.w3.org/1999/02/22-rdf-syntax-ns#'\n             \t\t\txmlns:exterms='http://www.example.org/terms/'>\n\t\t\t\t\t<rdf:Description rdf:about='http://www.example.org/index.html'>\n\t\t\t\t\t\t<exterms:creation-date>August 16, 1999</exterms:creation-date>\n\t\t\t\t\t</rdf:Description>\n\t\t\t\t</rdf:RDF>";
     // delete default prefixes
     global $default_prefixes;
     $backup = $default_prefixes;
     foreach ($default_prefixes as $name => $pref) {
         unset($default_prefixes[$name]);
     }
     $default_prefixes = array('foo' => RDF_NAMESPACE_URI);
     $model = new MemModel();
     $model->load($string);
     $nmsp = $model->getParsedNamespaces();
     $this->assertEqual($nmsp[RDF_NAMESPACE_URI], 'rdf');
     $default_prefixes = $backup;
 }

 function testRdfSerializer()
 {
     $_SESSION['test'] = 'Rdf- Parser Empty Resource test';
     $mod1 = new MemModel();
     $mod2 = new MemModel();
     $mod3 = new MemModel();
     $mod1->load('multipleTypes.rdf');
     $mod1->saveAs('mt1.rdf', 'rdf');
     $mod3->load('mt1.rdf');
     $mod2->load('multipleTypes.rdf');
     $_SESSION['mod1'] = $mod3;
     $_SESSIOn['mod2'] = $mod2;
     if ($mod3->equals($mod2)) {
         $pass = true;
     } else {
         $pass = false;
     }
     $this->assertTrue($pass);
 }

 /**
  * generates a test model containing given number of statements
  * and given indextype.
  *
  * @return Object MemModel $model
  * @param  int $num 
  * @param  int $des
  * @param  int $ind
  * @param  Object MemModel $needle
  */
 function _generateModel($num, $des, $ind, $needle)
 {
     $model = new MemModel();
     // generate Subjects
     for ($i = 0; $i < $num; $i++) {
         $subs[$i] = new Resource('http://www.example.org/Subject' . $i % 6);
     }
     // generate Predicates
     for ($i = 0; $i < $num; $i++) {
         $preds[$i] = new Resource('http://www.example.org/Predicate' . $i % 7);
     }
     // generate Objects
     for ($i = 0; $i < $num; $i++) {
         $objs[$i] = new Resource('http://www.example.org/Object' . $i % 5);
     }
     for ($i = 0; $i < $num; $i++) {
         $model->add(new Statement($subs[$i], $preds[$i], $objs[$i]));
     }
     $model->index($ind);
     return $model;
 }

/**
 * SPO (also known as "Triples" or "find(spo)") is an experimental minimal query language. 
 * An SPO query is a single triple pattern, with optional subject (parameter "s"), predicate (parameter "p"), 
 * and object (parameter "o", if a URIref, parameter "v" for a string literal). 
 * Absence of a parameter implies "any" for matching that slot of the triple pattern.
 *
 * @version  $Id: spo.php 268 2006-05-15 05:28:09Z tgauss $
 * @author Chris Bizer <[email protected]>
 * @author Phil Dawes <[email protected]>
 *
 * @package netapi
 * @todo Support typed literals.
 * @access	public
 */
function spoQuery($model, $serializer, $remove = false, $modelId = false)
{
    // Get SPO query from HTTP request
    if (isset($_REQUEST['s'])) {
        $subject = new Resource($_REQUEST['s']);
    } else {
        $subject = NULL;
    }
    if (isset($_REQUEST['p'])) {
        $predicate = new Resource($_REQUEST['p']);
    } else {
        $predicate = NULL;
    }
    if (isset($_REQUEST['o'])) {
        $object = new Resource($_REQUEST['o']);
    } else {
        if (isset($_REQUEST['v'])) {
            $object = new Literal($_REQUEST['v']);
        } else {
            $object = NULL;
        }
    }
    if (isset($_REQUEST['closure'])) {
        if (strtoupper($_REQUEST['closure']) == "TRUE") {
            $closure = True;
        } else {
            $closure = False;
        }
    } else {
        $closure = False;
    }
    $outm = new MemModel();
    $resultmodel = $model->find($subject, $predicate, $object);
    $it = $resultmodel->getStatementIterator();
    while ($it->hasNext()) {
        $stmt = $it->next();
        if ($remove) {
            $model->remove($stmt);
        } else {
            $outm->add(new Statement($stmt->subject(), $stmt->predicate(), $stmt->object()));
            if (is_a($stmt->object(), 'BlankNode') && $closure == True) {
                getBNodeClosure($stmt->object(), $model, $outm);
            }
            if (is_a($stmt->subject(), 'BlankNode') && $closure == True) {
                getBNodeClosure($stmt->subject(), $model, $outm);
            }
        }
    }
    if ($remove) {
        if (substr($modelId, 0, 5) == "file:") {
            $model->saveAs(substr($modelId, 5));
        }
        if ($resultmodel->size() > 0) {
            header('200 - OK');
            echo "200 - OK";
        } else {
            echo "No matching statements";
        }
    } else {
        echo $serializer->Serialize($outm);
    }
    $outm->close();
}

 function _generateRDF()
 {
     $model = new MemModel();
     $model->setBaseURI($this->doclink);
     $proc = new xsltprocessor();
     include_once RDFAPI_INCLUDE_DIR . PACKAGE_SYNTAX_RDF;
     $pars = new RdfParser();
     foreach ($this->stylelink as $key => $value) {
         $xsl = new DomDocument();
         $xsl->load($value);
         $proc->importStyleSheet($xsl);
         $model->addModel($pars->generateModel($proc->transformToXML($this->domdoc), $this->doclink));
     }
     return $model;
 }

<?php 
// Include RAP
define("RDFAPI_INCLUDE_DIR", "./../api/");
include RDFAPI_INCLUDE_DIR . "RdfAPI.php";
## 1. Connect to MsAccess database (via ODBC)
## ------------------------------------------
// Connect to MsAccess (rdf_db DSN) database using connection settings
// defined in constants.php :
$rdf_database = new DbStore();
## 2. Store a memory model in database.
## ------------------------------------
// Load an RDF-Documtent into a memory model
// Filename of an RDF document
$base = "example1.rdf";
// Create a new memory model
$memModel = new MemModel();
// Load and parse document
$memModel->load($base);
// Now store the model in database
// An unique modelURI will be generated
$rdf_database->putModel($memModel);
// You can also provide an URI for the model to be stored
$modelURI = "example1.rdf";
// But then you must check if there already is a model with the same modelURI
// otherwise the method putModel() will return FALSE
if ($rdf_database->modelExists($modelURI)) {
    echo "Model with the same URI: '{$modelURI}' already exists";
} else {
    $rdf_database->putModel($memModel, $modelURI);
}
## 3. Create a new database model

 private function addBookToModel(SimpleXMLElement $item, MemModel $model)
 {
     $itemresource = new Resource($this->uri);
     // rdf:type
     $model->add(new Statement($itemresource, new Resource(RDF_NAMESPACE_URI . RDF_TYPE), new Resource("http://sites.wiwiss.fu-berlin.de/suhl/bizer/bookmashup/simpleCommerceVocab01.rdf#Book")));
     // homepage (link to details page @ amazon)
     //$model->add(new Statement($itemresource ,new Resource("http://xmlns.com/foaf/0.1/homepage"),new Resource($item->DetailPageURL)));
     // label
     $model->add(new Statement($itemresource, new Resource("http://www.w3.org/2000/01/rdf-schema#label"), new Literal((string) $item->ItemAttributes->Title)));
     // date
     $model->add(new Statement($itemresource, new Resource("http://purl.org/dc/elements/1.1/date"), new Literal((string) $item->ItemAttributes->PublicationDate)));
     // title
     $model->add(new Statement($itemresource, new Resource("http://purl.org/dc/elements/1.1/title"), new Literal((string) $item->ItemAttributes->Title)));
     //large image
     $model->add(new Statement($itemresource, new Resource("http://xmlns.com/foaf/0.1/depiction"), new Resource((string) $item->LargeImage->URL)));
     // thumbnail
     $model->add(new Statement($itemresource, new Resource("http://xmlns.com/foaf/0.1/thumbnail"), new Resource((string) $item->SmallImage->URL)));
     // isbn
     $model->add(new Statement($itemresource, new Resource("http://purl.org/dc/elements/1.1/identifier"), new Resource("urn:ISBN:" . $item->ItemAttributes->ISBN)));
     // publisher
     $model->add(new Statement($itemresource, new Resource("http://purl.org/dc/elements/1.1/publisher"), new Literal((string) $item->ItemAttributes->Label)));
     // format
     if (isset($item->ItemAttributes->format)) {
         $model->add(new Statement($itemresource, new Resource("http://purl.org/dc/elements/1.1/format"), new Literal((string) $item->ItemAttributes->format)));
     }
     if (isset($item->ItemAttributes->Binding)) {
         $model->add(new Statement($itemresource, new Resource("http://purl.org/dc/elements/1.1/format"), new Literal((string) $item->ItemAttributes->Binding)));
     }
     // reviews
     $i = 1;
     foreach ($item->EditorialReviews->EditorialReview as $index => $review) {
         $newuri = str_replace("/books/", "/reviews/", $this->uri);
         $pos = strrpos($newuri, "/");
         $review = new Resource($newuri . "_" . $index . $i);
         $model->add(new Statement($itemresource, new Resource("http://dannyayers.com/xmlns/rev/#hasReview"), $review));
         $model->add(new Statement($review, new Resource("http://www.w3.org/2000/01/rdf-schema#label"), new Literal("Review number " . $i . " about: " . $item->ItemAttributes->Title)));
         $i++;
     }
     // author
     $newuri = str_replace("/books/", "/persons/", $this->uri);
     $pos = strrpos($newuri, "/");
     if (isset($item->ItemAttributes->Author)) {
         foreach ($item->ItemAttributes->Author as $k => $author) {
             $authorUri = new Resource(substr($newuri, 0, $pos + 1) . urlencode($author));
             $model->add(new Statement($itemresource, new Resource("http://purl.org/dc/elements/1.1/creator"), $authorUri));
             $model->add(new Statement($authorUri, new Resource("http://www.w3.org/2000/01/rdf-schema#label"), new Literal((string) $author)));
         }
     }
     // subject(s)
     $newuri = str_replace("/books/", "/subject/", $this->uri);
     $skosSubject = new Resource("http://www.w3.org/2004/02/skos/core#subject");
     $pos = strrpos($newuri, "/");
     if (isset($item->Subjects)) {
         foreach ($item->Subjects as $k => $subjects) {
             foreach ($subjects as $kk => $subject) {
                 $subjectUri = new Resource(substr($newuri, 0, $pos + 1) . urlencode($subject));
                 $model->add(new Statement($itemresource, $skosSubject, $subjectUri));
                 $model->add(new Statement($subjectUri, new Resource("http://www.w3.org/2000/01/rdf-schema#label"), new Literal((string) $subject)));
             }
         }
     }
     if (isset($item->ItemAttributes->Creator)) {
         foreach ($item->ItemAttributes->Creator as $key => $creator) {
             $creatorUri = new Resource(substr($newuri, 0, $pos + 1) . urlencode($creator));
             $model->add(new Statement($itemresource, new Resource("http://purl.org/dc/elements/1.1/creator"), $creatorUri));
             $model->add(new Statement($creatorUri, new Resource("http://www.w3.org/2000/01/rdf-schema#label"), new Literal((string) $creator)));
         }
     }
     // amazon offer
     $newuri = str_replace("/books/", "/offers/", $this->uri);
     $pos = strrpos($newuri, "/");
     $offer = new Resource($newuri . "amazonOffer");
     $model->add(new Statement($itemresource, new Resource("http://sites.wiwiss.fu-berlin.de/suhl/bizer/bookmashup/simpleCommerceVocab01.rdf#hasOffer"), $offer));
     $model->add(new Statement($offer, new Resource("http://www.w3.org/2000/01/rdf-schema#label"), new Literal("Offer for the book with the ISBN: " . $item->ItemAttributes->ISBN)));
     // create OFFER from google
     $this->addGoogleOffersToModel($model, $this->uri);
     //
     $model->add(new Statement(new Resource($this->document), new Resource("http://www.w3.org/2000/01/rdf-schema#label"), new Literal("RDF document about the book: " . $item->ItemAttributes->Title)));
 }

 /**
  * Constructs a result graph.
  *
  * @param  array         $arVartable       A table containing the result vars and their bindings
  * @param  GraphPattern  $constructPattern The CONSTRUCT pattern
  * @return MemModel      The result graph which matches the CONSTRUCT pattern
  */
 protected function constructGraph($arVartable, $constructPattern)
 {
     $resultGraph = new MemModel();
     if (!$arVartable) {
         return $resultGraph;
     }
     $tp = $constructPattern->getTriplePatterns();
     $bnode = 0;
     foreach ($arVartable as $value) {
         foreach ($tp as $triple) {
             $sub = $triple->getSubject();
             $pred = $triple->getPredicate();
             $obj = $triple->getObject();
             if (is_string($sub) && $sub[1] == '_') {
                 $sub = new BlankNode("_bN" . $bnode);
             }
             if (is_string($pred) && $pred[1] == '_') {
                 $pred = new BlankNode("_bN" . $bnode);
             }
             if (is_string($obj) && $obj[1] == '_') {
                 $obj = new BlankNode("_bN" . $bnode);
             }
             if (is_string($sub)) {
                 $sub = $value[$sub];
             }
             if (is_string($pred)) {
                 $pred = $value[$pred];
             }
             if (is_string($obj)) {
                 $obj = $value[$obj];
             }
             if ($sub !== "" && $pred !== "" && $obj !== "") {
                 $resultGraph->add(new Statement($sub, $pred, $obj));
             }
         }
         $bnode++;
     }
     return $resultGraph;
 }

 /**
  * Reifies a statement.
  * Returns a new MemModel that is the reification of the statement.
  * For naming the statement's bNode a Model or bNodeID must be passed to the method.   
  *
  * @access	public 
  * @param		mixed	&$model_or_bNodeID
  * @return	object	model
  */
 function &reify(&$model_or_bNodeID)
 {
     if (is_a($model_or_bNodeID, 'MemModel')) {
         // parameter is model
         $statementModel = new MemModel($model_or_bNodeID->getBaseURI());
         $thisStatement = new BlankNode($model_or_bNodeID);
     } else {
         // parameter is bNodeID
         $statementModel = new MemModel();
         $thisStatement =& $model_or_bNodeID;
     }
     $RDFstatement = new Resource(RDF_NAMESPACE_URI . RDF_STATEMENT);
     $RDFtype = new Resource(RDF_NAMESPACE_URI . RDF_TYPE);
     $RDFsubject = new Resource(RDF_NAMESPACE_URI . RDF_SUBJECT);
     $RDFpredicate = new Resource(RDF_NAMESPACE_URI . RDF_PREDICATE);
     $RDFobject = new Resource(RDF_NAMESPACE_URI . RDF_OBJECT);
     $statementModel->add(new Statement($thisStatement, $RDFtype, $RDFstatement));
     $statementModel->add(new Statement($thisStatement, $RDFsubject, $this->getSubject()));
     $statementModel->add(new Statement($thisStatement, $RDFpredicate, $this->getPredicate()));
     $statementModel->add(new Statement($thisStatement, $RDFobject, $this->Object()));
     return $statementModel;
 }

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<head>
	<title>Test Traverse MemModel</title>
</head>
<body>

<?php 
define("RDFAPI_INCLUDE_DIR", "./../api/");
include RDFAPI_INCLUDE_DIR . "RdfAPI.php";
// Filename of an RDF document
$base = "example1.rdf";
// Create a new MemModel
$model = new MemModel();
// Load and parse document
$model->load($base);
// Get Iterator from model
$it = $model->getStatementIterator();
// Traverse model and output statements
while ($it->hasNext()) {
    $statement = $it->next();
    echo "Statement number: " . $it->getCurrentPosition() . "<BR>";
    echo "Subject: " . $statement->getLabelSubject() . "<BR>";
    echo "Predicate: " . $statement->getLabelPredicate() . "<BR>";
    echo "Object: " . $statement->getLabelObject() . "<P>";
}
// Move to the last statement and print it
$it->moveLast();
$statement = $it->current();
// Traverse model backward and print statements
echo $statement->toString() . "<BR>";

 /**
  * Create a MemModel containing only the base triples (without inferred 
  * statements) of the current InfModelB.
  *
  * @return object MemModel
  * @access public
  */
 function &getBaseMemModel()
 {
     $return = new MemModel();
     $return->setBaseURI($this->baseURI);
     foreach ($this->triples as $statement) {
         $return->add($statement);
     }
     $retun->addParsedNamespaces($this->getParsedNamespaces());
     return $return;
 }

 function testNestBlankAtEnd()
 {
     $mod = new MemModel();
     $b3 = new BlankNode($mod);
     $mod->add(new Statement(new Resource('http://example.org/foo'), new Resource("http://example.org/bar2"), $b3));
     $ser = new N3Serializer();
     $ser->setCompress(true);
     $ser->setNest(true);
     $str = $ser->serialize($mod);
     //test if it can be loaded
     $par = new N3Parser();
     $mod2 = $par->parse2model($str, false);
     //var_dump($str, $mod2->triples);
     $this->compareModelsIgnoringBlankNodes($mod, $mod2);
 }