source: Dev/branches/rest-dojo-ui/Cartis/rdfapi/util/ModelComparator.php @ 312

<?php

// ----------------------------------------------------------------------------------
// Class: ModelComparator
// ----------------------------------------------------------------------------------


/**
 * This class compares to models. This comparator bases on the labelling algorithm 
 * described in <href="http://www.hpl.hp.com/techreports/2003/HPL-2003-142.pdf" >Signing RDF Graphs</href> 
 * by Jeremy J. Carroll.
 *
 *
 * @version  $Id$
 * @author Tobias Gauß <tobias.gauss at web.de>
 *
 * @package utility
 * @access      public
 *
 **/ 
 class ModelComparator extends Object {
        
        /**
        * Compares two models.
        *
        * @param $thisModel First Model.
        * @param $thatModel Second Model.
        *
        * @return boolean
        */
        function compare($thisModel, $thatModel){
        
        $thisModeltriples = null;
        $thatModeltriples = null;
        
                if(is_a($thisModel,"DbModel")){
                        $thisModeltriples =     $thisModel->getMemModel();
                }else{
                        $thisModeltriples =     $thisModel;
                }
                
                if(is_a($thatModel,"DbModel")){
                        $thatModeltriples =     $thatModel->getMemModel();
                }else{
                        $thatModeltriples =     $thatModel;
                }
                        
                $sortArray1 = ModelComparator::buildSortArray($thisModeltriples->triples);
                $sortArray2 = ModelComparator::buildSortArray($thatModeltriples->triples);      
                
                $renamedArray1 = ModelComparator::renameBlanks($sortArray1);
                $renamedArray2 = ModelComparator::renameBlanks($sortArray2);
                
                return ModelComparator::compareTriples($renamedArray1,$renamedArray2);
        }
                
        
        /**
        * Builds a sorted array. 
        *
        * @param $tripleList A List that contains the models triples.
        *
        * @return Array
        */
        function buildSortArray($tripleList){
                $sortedArray = Array();
                
                foreach($tripleList as $index => $triple){
                        $sub = null;
                        $obj = null;
                        $orgSub  = $triple->getSubject();
                        $orgObj  = $triple->getObject();
                        
                        if(is_a($orgSub,"Blanknode")){
                                $sub = $orgSub->getID();
                                $triple->subj = new Blanknode("~");
                        }
                        if(is_a($orgObj,"Blanknode")){
                                $obj = $orgObj->getID();
                                $triple->obj = new Blanknode("~");
                        }
                        $sortedArray[$index]['string']  = $triple->toString();
                        $sortedArray[$index]['index']  = $index;
                        $sortedArray[$index]['triple'] = $triple;
                        $sortedArray[$index]['sub']    = $sub;
                        $sortedArray[$index]['obj']    = $obj;  
                }
                sort($sortedArray);
                return $sortedArray;
        }
        
        /**
        * Renames the models Blanknodes. 
        *
        * @param $sortedArray A List that contains the models triples.
        *
        * @return Array
        */
        function renameBlanks($sortedArray){
        $i = 0;
        $labelmap = Array();
                
                foreach ($sortedArray as $value){       
                        //new label
                        if($value['sub']!=null){
                                $label = null;
                                if(isset($labelmap[$value['sub']])){
                                        $label = $labelmap[$value['sub']];
                                        $value['triple']->subj = new BlankNode($labelmap[$value['sub']]);
                                }else{
                                        $label = $i."Bnode";
                                        $labelmap[$value['sub']]=$label;
                                        $value['triple']->subj = new BlankNode($labelmap[$value['sub']]);
                                        $i++;
                                }
                        }
                        
                        if($value['obj']!=null){
                                $label = null;
                                if(isset($labelmap[$value['obj']])){
                                        $label = $labelmap[$value['obj']];
                                        $value['triple']->obj = new BlankNode($labelmap[$value['obj']]);
                                }else{
                                        $label = $i."Bnode";
                                        $labelmap[$value['obj']]=$label;
                                        $value['triple']->obj = new BlankNode($labelmap[$value['obj']]);
                                        $i++;
                                }
                        }
                        
                }
                return $sortedArray;
        
        }
        
        /**
        * Compares the Triples in the lists. 
        *
        * @param $tripleList A List that contains the models triples.
        * @param $tripleList A List that contains the models triples.
        *
        * @return boolean
        */
        function compareTriples($array1, $array2){
                foreach($array1 as $key => $value){
                        if(!$value['triple']->equals($array2[$key]['triple']))
                                return false;
                }
                return true;
        
        }
        
 
 }
 
 
 
 ?>